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Posts Tagged ‘Tidal Turbines’

NAO NAKANISHI, Reuters, October 5, 2009

PelamisWaveFarm_PelamisWavePowerA first attempt fell victim to the crisis: now in the docks of Scotland’s ancient capital, a second-generation scarlet Sea Snake is being prepared to harness the waves of Britain’s northern islands to generate electricity.

Dwarfed by 180 metres of tubing, scores of engineers clamber over the device, which is designed to dip and ride the swelling sea with each move being converted into power to be channelled through subsea cables.

Due to be installed next spring at the European Marine Energy Centre (EMEC) in Orkney, northern Scotland, the wave power generator was ordered by German power company E.ON, reflecting serious interest in an emerging technology which is much more expensive than offshore wind.

Interest from the utility companies is driven by regulatory requirements to cut carbon emissions from electricity generation, and it helps in a capital-intensive sector.

Venture capitalists interested in clean tech projects typically have shorter horizons for required returns than the 10-20 years such projects can take, so the utilities’ deeper pockets and solid capital base are useful.

“Our view … is this is a 2020 market place,” said Amaan Lafayette, E.ON’s marine development manager. “We would like to see a small-scale plant of our own in water in 2015-2017, built on what we are doing here. It’s a kind of generation we haven’t done before.”

The World Energy Council has estimated the market potential for wave energy at more than 2,000 terawatt hours a year — or about 10% of world electricity consumption — representing capital expenditure of more than 500 billion pounds ($790 billion).

Island nation Britain has a leading role in developing the technology for marine power, which government advisor the Carbon Trust says could in future account for 20% of the country’s electricity. The government is stepping up support as part of a 405 million pound investment in renewable energy to help its ambition of cutting carbon emissions by 80% by 2050 from 1990 levels, while securing energy supply. (The challenge is more about getting to a place where we are comparable with other renewable technologies… We want to get somewhere around offshore wind,” said Lafayette.)

Britain’s Crown Estate, which owns the seabed within 12 nautical miles of the coast, is also holding a competition for a commercial marine energy project in Pentland Firth in northern Scotland.

Besides wave power, Britain is testing systems to extract the energy from tides: private company Marine Current Turbines Ltd (MCT) last year opened the world’s first large-scale tidal turbine SeaGen in Northern Ireland.

DEVELOPING LIKE WIND

wave_power_pelamis“We are often compared to the wind industry 20 years ago,” said Andrew Scott, project development manager at Pelamis Wave Power Ltd, which is developing the Sea Snake system, known as P2. Standing beside the train-sized serpent, Pelamis’ Scott said wave power projects are taking a variety of forms, which he said was similar to the development of the wind turbine. “You had vertical axis, horizontal axis and every kind of shapes before the industry consolidated on what you know as acceptable average modern day turbines.”

The Edinburgh Snake follows a pioneering commercial wave power project the company set up in Portugal last September, out of action since the collapse of Australian-based infrastructure group Babcock & Brown which held a majority share. “It’s easy to develop your prototypes and models in the lab, but as soon as you put them in water, it swallows capital,” said John Liljelund, CEO of Finnish wave energy firm AW-Energy, which just received $4.4 million from the European Union to develop its WaveRoller concept in Portugal.

At present, industry executives say marine power costs about double that from offshore wind farms, which require investment of around 2-3 million euros per megawatt. Solar panels cost about 3-4 million per megawatt, and solar thermal mirror power about 5 million.

UTILITY ACTION

Other utility companies involved in wave power trials include Spain’s Iberdrola, which has a small experimental wave farm using floating buoys called “Power Take- offs” off the coast of northern Spain. It is examining sites for a subsea tidal turbine project made by Norwegian company Hammerfest Strom.

Countries developing the technology besides Britain include Portugal, Ireland, Spain, South Korea and the United States: about 100 companies are vying for a share of the market, but only a handful have tested their work in the ocean.

Privately owned Pelamis has focussed on wave energy since 1998, has its own full-scale factory in Leith dock and sees more orders for the second generation in prospect.

Lafayette said E.ON examined more than 100 devices since 2001 before picking Sea Snake for its first ocean project, a three-year test: “They have a demonstrable track record … and commercial focus and business focus.”

A single Sea Snake has capacity of 750 kilowatts: by around 2015, Pelamis hopes each unit will have capacity of 20 megawatts, or enough to power about 30,000 homes.

Neither Pelamis nor E.ON would elaborate on the cost of the Sea Snake, but they said the goal is to bring it down to the level of offshore wind farms.

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JAMES RICKMAN, Seeking Alpha, June 8, 2009

wave-ocean-blue-sea-water-white-foam-photoOceans cover more than 70% of the Earth’s surface. As the world’s largest solar collectors, oceans generate thermal energy from the sun. They also produce mechanical energy from the tides and waves. Even though the sun affects all ocean activity, the gravitational pull of the moon primarily drives the tides, and the wind powers the ocean waves.

Wave energy is the capture of the power from waves on the surface of the ocean. It is one of the newer forms of renewable or ‘green’ energy under development, not as advanced as solar energy, fuel cells, wind energy, ethanol, geothermal companies, and flywheels. However, interest in wave energy is increasing and may be the wave of the future in coastal areas according to many sources including the International Energy Agency Implementing Agreement on Ocean Energy Systems (Report 2009).

Although fewer than 12 MW of ocean power capacity has been installed to date worldwide, we find a significant increase of investments reaching over $2 billion for R&D worldwide within the ocean power market including the development of commercial ocean wave power combination wind farms within the next three years.

Tidal turbines are a new technology that can be used in many tidal areas. They are basically wind turbines that can be located anywhere there is strong tidal flow. Because water is about 800 times denser than air, tidal turbines will have to be much sturdier than wind turbines. They will be heavier and more expensive to build but will be able to capture more energy. For example, in the U.S. Pacific Northwest region alone, it’s feasible that wave energy could produce 40–70 kilowatts (kW) per meter (3.3 feet) of western coastline. Renewable energy analysts believe there is enough energy in the ocean waves to provide up to 2 terawatts of electricity.

Companies to Watch in the Developing Wave Power Industry:

Siemens AG (SI) is a joint venture partner of Voith Siemens Hydro Power Generation, a leader in advanced hydro power technology and services, which owns Wavegen, Scotland’s first wave power company. Wavegen’s device is known as an oscillating water column, which is normally sited at the shoreline rather than in open water. A small facility is already connected to the Scottish power grid, and the company is working on another project in Northern Spain.

Ocean Power Technologies, Inc (OPTT) develops proprietary systems that generate electricity through ocean waves. Its PowerBuoy system is used to supply electricity to local and regional electric power grids. Iberdrola hired the company to build and operate a small wave power station off Santona, Spain, and is talking with French oil major Total (TOT) about another wave energy project off the French coast. It is also working on projects in England, Scotland, Hawaii, and Oregon.

Pelamis Wave Power, formerly known as Ocean Power Delivery, is a privately held company which has several owners including various venture capital funds, General Electric Energy (GE) and Norsk Hydro ADR (NHYDY.PK). Pelamis Wave Power is an excellent example of Scottish success in developing groundbreaking technology which may put Scotland at the forefront of Europe’s renewable revolution and create over 18,000 green high wage jobs in Scotland over the next decade. The Pelamis project is also being studied by Chevron (CVX).

Endesa SA ADS (ELEYY.PK) is a Spanish electric utility which is developing, in partnership with Pelamis, the world’s first full scale commercial wave power farm off Aguçadoura, Portugal which powers over 15,000 homes. A second phase of the project is now planned to increase the installed capacity from 2.25MW to 21MW using a further 25 Pelamis machines.

RWE AG ADR (RWEOY.PK) is a German management holding company with six divisions involved in power and energy. It is developing wave power stations in Siadar Bay on the Isle of Lewis off the coast of Scotland.

Australia’s Oceanlinx offers an oscillating wave column design and counts Germany’s largest power generator RWE as an investor. It has multiple projects in Australia and the U.S., as well as South Africa, Mexico, and Britain.

Alstom (AOMFF.PK) has also announced development in the promising but challenging field of capturing energy from waves and tides adding to the further interest from major renewable power developers in this emerging industry.

The U.S. Department of Energy has announced several wave energy developments including a cost-shared value of over $18 million, under the DOE’s competitive solicitation for Advanced Water Power Projects. The projects will advance commercial viability, cost-competitiveness, and market acceptance of new technologies that can harness renewable energy from oceans and rivers. The DOE has selected the following organizations and projects for grant awards:

First Topic Area: Technology Development (Up to $600,000 for up to two years)

Electric Power Research Institute, Inc (EPRI) (Palo Alto, Calif.) Fish-friendly hydropower turbine development & deployment. EPRI will address the additional developmental engineering required to prepare a more efficient and environmentally friendly hydropower turbine for the commercial market and allow it to compete with traditional designs.

Verdant Power Inc. (New York, N.Y.) Improved structure and fabrication of large, high-power kinetic hydropower systems rotors. Verdant will design, analyze, develop for manufacture, fabricate and thoroughly test an improved turbine blade design structure to allow for larger, higher-power and more cost-effective tidal power turbines.

Public Utility District #1 of Snohomish County (SnoPUD) (Everett, Wash.) Puget Sound Tidal Energy In-Water Testing and Development Project. SnoPUD will conduct in-water testing and demonstration of tidal flow technology as a first step toward potential construction of a commercial-scale power plant. The specific goal of this proposal is to complete engineering design and obtain construction approvals for a Puget Sound tidal pilot demonstration plant in the Admiralty Inlet region of the Sound.

Pacific Gas and Electric Company – San Francisco, Calif. WaveConnect Wave Energy In-Water Testing and Development Project. PG&E will complete engineering design, conduct baseline environmental studies, and submit all license construction and operation applications required for a wave energy demonstration plant for the Humboldt WaveConnect site in Northern California.

Concepts ETI, Inc (White River Junction, Vt.) Development and Demonstration of an Ocean Wave Converter (OWC) Power System. Concepts ETI will prepare detailed design, manufacturing and installation drawings of an OWC. They will then manufacture and install the system in Maui, Hawaii.

Lockheed Martin Corporation (LMT) – Manassas, Va., Advanced Composite Ocean Thermal Energy Conversion – “OTEC”, cold water pipe project. Lockheed Martin will validate manufacturing techniques for coldwater pipes critical to OTEC in order to help create a more cost-effective OTEC system.

Second Topic Area, Market Acceleration (Award size: up to $500,000)

Electric Power Research Institute (Palo Alto, Calif.) Wave Energy Resource Assessment and GIS Database for the U.S. EPRI will determine the naturally available resource base and the maximum practicable extractable wave energy resource in the U.S., as well as the annual electrical energy which could be produced by typical wave energy conversion devices from that resource.

Georgia Tech Research Corporation (Atlanta, Ga.) Assessment of Energy Production Potential from Tidal Streams in the U.S. Georgia Tech will utilize an advanced ocean circulation numerical model to predict tidal currents and compute both available and effective power densities for distribution to potential project developers and the general public.

Re Vision Consulting, LLC (Sacramento, Calif.) Best Siting Practices for Marine and Hydrokinetic Technologies With Respect to Environmental and Navigational Impacts. Re Vision will establish baseline, technology-based scenarios to identify potential concerns in the siting of marine and hydrokinetic energy devices, and to provide information and data to industry and regulators.

Pacific Energy Ventures, LLC (Portland, Ore.) Siting Protocol for Marine and Hydrokinetic Energy Projects. Pacific Energy Ventures will bring together a multi-disciplinary team in an iterative and collaborative process to develop, review, and recommend how emerging hydrokinetic technologies can be sited to minimize environmental impacts.

PCCI, Inc. (Alexandria, Va.) Marine and Hydrokinetic Renewable Energy Technologies: Identification of Potential Navigational Impacts and Mitigation Measures. PCCI will provide improved guidance to help developers understand how marine and hydrokinetic devices can be sited to minimize navigational impact and to expedite the U.S. Coast Guard review process.

Science Applications International Corporation (SAI) – San Diego, Calif., International Standards Development for Marine and Hydrokinetic Renewable Energy. SAIC will assist in the development of relevant marine and hydrokinetic energy industry standards, provide consistency and predictability to their development, and increase U.S. industry’s collaboration and representation in the development process.

Third Topic Area, National Marine Energy Centers (Award size: up to $1.25 million for up to five years)

Oregon State University, and University of Washington – Northwest National Marine Renewable Energy Center. OSU and UW will partner to develop the Northwest National Marine Renewable Energy Center with a full range of capabilities to support wave and tidal energy development for the U.S. Center activities are structured to: facilitate device commercialization, inform regulatory and policy decisions, and close key gaps in understanding.

University of Hawaii (Honolulu, Hawaii) National Renewable Marine Energy Center in Hawaii will facilitate the development and implementation of commercial wave energy systems and to assist the private sector in moving ocean thermal energy conversion systems beyond proof-of-concept to pre-commercialization, long-term testing.

Types of Hydro Turbines

There are two main types of hydro turbines: impulse and reaction. The type of hydropower turbine selected for a project is based on the height of standing water— the flow, or volume of water, at the site. Other deciding factors include how deep the turbine must be set, efficiency, and cost.

Impulse Turbines

The impulse turbine generally uses the velocity of the water to move the runner and discharges to atmospheric pressure. The water stream hits each bucket on the runner. There is no suction on the down side of the turbine, and the water flows out the bottom of the turbine housing after hitting the runner. An impulse turbine, for example Pelton or Cross-Flow is generally suitable for high head, low flow applications.

Reaction Turbines

A reaction turbine develops power from the combined action of pressure and moving water. The runner is placed directly in the water stream flowing over the blades rather than striking each individually. Reaction turbines include the Propeller, Bulb, Straflo, Tube, Kaplan, Francis or Kenetic are generally used for sites with lower head and higher flows than compared with the impulse turbines.

Types of Hydropower Plants

There are three types of hydropower facilities: impoundment, diversion, and pumped storage. Some hydropower plants use dams and some do not.

Many dams were built for other purposes and hydropower was added later. In the United States, there are about 80,000 dams of which only 2,400 produce power. The other dams are for recreation, stock/farm ponds, flood control, water supply, and irrigation. Hydropower plants range in size from small systems for a home or village to large projects producing electricity for utilities.

Impoundment

The most common type of hydroelectric power plant (above image) is an impoundment facility. An impoundment facility, typically a large hydropower system, uses a dam to store river water in a reservoir. Water released from the reservoir flows through a turbine, spinning it, which in turn activates a generator to produce electricity. The water may be released either to meet changing electricity needs or to maintain a constant reservoir level.

The Future of Ocean and Wave Energy

Wave energy devices extract energy directly from surface waves or from pressure fluctuations below the surface. Renewable energy analysts believe there is enough energy in the ocean waves to provide up to 2 terawatts of electricity. (A terawatt is equal to a trillion watts.)

Wave energy rich areas of the world include the western coasts of Scotland, northern Canada, southern Africa, Japan, Australia, and the northeastern and northwestern coasts of the United States. In the Pacific Northwest alone, it’s feasible that wave energy could produce 40–70 kilowatts (kW) per meter (3.3 feet) of western coastline. The West Coast of the United States is more than a 1,000 miles long.
In general, careful site selection is the key to keeping the environmental impacts of wave energy systems to a minimum. Wave energy system planners can choose sites that preserve scenic shorefronts. They also can avoid areas where wave energy systems can significantly alter flow patterns of sediment on the ocean floor.

Economically, wave energy systems are just beginning to compete with traditional power sources. However, the costs to produce wave energy are quickly coming down. Some European experts predict that wave power devices will soon find lucrative niche markets. Once built, they have low operation and maintenance costs because the fuel they use — seawater — is FREE.

The current cost of wave energy vs. traditional electric power sources?

It has been estimated that improving technology and economies of scale will allow wave generators to produce electricity at a cost comparable to wind-driven turbines, which produce energy at about 4.5 cents kWh.

For now, the best wave generator technology in place in the United Kingdom is producing energy at an average projected/assessed cost of 6.7 cents kWh.

In comparison, electricity generated by large scale coal burning power plants costs about 2.6 cents per kilowatt-hour. Combined-cycle natural gas turbine technology, the primary source of new electric power capacity is about 3 cents per kilowatt hour or higher. It is not unusual to average costs of 5 cents per kilowatt-hour and up for municipal utilities districts.

Currently, the United States, Brazil, Europe, Scotland, Germany, Portugal, Canada and France all lead the developing wave energy industry that will return 30% growth or more for the next five years.

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PETER BROWN, EnergyCurrent.com, February 16, 2009

stromnessOn a Monday morning in May last year, the Atlantic tide set a turbine in motion on the seabed off Orkney, and the energy captured was connected to the national grid. It was, said Jim Mather, Scotland’s Minister for Enterprise, Energy and Tourism, a “massive step forward”.

The amount of electricity generated may have been tiny, but for marine engineers the significance was huge. Their industry had stopped paddling and started to swim.

For small companies trying to get wave or tide devices off the drawing board and into the sea, many problems lie in wait. All turbines, whether they sit on the seabed or float, must withstand that once-in-a-century wave that could be a thousand times more powerful than the average. Conditions vary with the seasons and the seabed. A device that works in a fjord might not function in a firth. Rigorous, long-term testing is therefore vital.

“There are parallels with wind,” says Alan Mortimer, head of renewables policy at Scottish Power. “Many different types of turbine were proposed in the early Eighties. They boiled down to a small number of successful concepts. The same needs to happen with marine devices, but the difference is that they need to be full- size just to be tested.

“To get a reasonable number of prototypes into the water costs millions. What these small companies need is capital support.”

That, however, is hard to find. The Wave and Tidal Energy Support Scheme (Wates), which put GBP13.5 million into promising technologies, is now closed. Last year the Scottish Government offered the 10m Saltire Prize for a commercially viable scheme, but the Institution of Mechanical Engineers (IMechE), in its recent report Marine Energy: More Than Just a Drop in the Ocean?, called on the Government to provide another 40m.

This would go towards schemes to be tested at EMEC, the European Marine Energy Centre, which has two supported sites, with grid access, at Orkney. It was there that an Irish company, OpenHydro, made the grid breakthrough last year. “It’s desperately important that we grasp the nettle now,” says William Banks, IMechE’s president. “We have the micro-systems in place and I’d like to see them developed to the macro stage. However, unless we do that step by step, we’ll be in trouble.”

An estimated 50 teams are working around the world on marine energy. The danger is that Britain, and Scotland in particular, could lose the race, even though, as Alex Salmond, Scotland’s First Minister, says, “Scotland has a marine energy resource which is unrivalled in Europe.”

Scotland has a quarter of Europe’s tidal resources and a tenth of its wave potential.

Around 1,000 people work in Scottish marine energy, but that figure could billow. “You’re talking about an exercise that could transform the marine industry into something equivalent to oil and gas,” says Martin McAdam, whose company, Aquamarine Power, is growing fast.

Among his rivals in Scotland are AWS Ocean Energy, based near Inverness, with Archimedes, a submerged wave machine; Hammerfest UK, which wants to develop three 60MW tidal sites and is working with Scottish Power; Pelamis Wave Power, who are based in Edinburgh; and Scotrenewables, based in Orkney, who are currently developing a floating tidal turbine.

Politicians need to be educated about marine energy’s potential, says Banks. Indeed, IMechE has highlighted the need for sustained political leadership if what many see as the biggest problem – that of the grid – is to be solved. Why bring energy onshore if it can’t then reach homes?

“Grids were built to connect large power stations to cities. Now you’re going to have electricity generated all over the countryside. It’s a huge challenge,” says McAdam.

“We have had meetings with Ofgen and the national grid companies and we’re outlining the need to have grids to support at least 3,000MW of energy by 2020. That is definitely possible.” McAdam adds: “A European undersea grid is also being promoted and we’re very supportive of that.”

Such a system would help to overcome a frequent objection to renewables – their fickleness. If waves were strong in Scotland, Finland or France could benefit, and vice versa.

Another challenge is the cost of installation. “At the moment we’re competing with oil and gas for boats,” says McAdam. “We need to move away from using heavy-lift, jack-up vessels.” The answer might be devices that can be floated into position and then weighted down.

The race between suppliers is speeding up. Permission for a 4MW station at Siadar, off Lewis in the Western Isles, has just been granted to Wavegen, based in Inverness, and Npower Renewables. It could power about 1,500 homes, creating 70 jobs.

Among the success stories are the three 140-metre, red tubes developed by Pelamis (named after a sea serpent) which already float off the northern Portuguese coast at Aguadoura. More Pelamis turbines are to be installed at EMEC, along with Aquamarine’s wave device Oyster.

Oyster is basically a giant flap which feeds wave energy onshore to be converted to electricity. It has already been made, at a former oil and gas plant at Nigg, north of Inverness. A high- pressure pipeline was completed in December and a hydro-electric station will be installed this spring. In the summer, Oyster will finally be bolted to piles hammered into the seabed.

Unlike wave energy, tidal power needs a channel between two land masses – and in the roaring Pentland Firth, between Caithness and Orkney, Scotland has what has been called “the Saudi Arabia of marine power”, Europe’s largest tidal resource. To exploit it, a GBP2 million contract to build Aquamarine’s tidal power device, Neptune, was awarded last month. It will be tested at EMEC.

Elsewhere, SeaGen, an “underwater windmill” developed by a Bristol company, has just generated 1.2MW near the mouth of Strangford Lough, Northern Ireland.
But the most controversial of Britain’s tidal energy schemes is, of course, in the Severn Estuary, where a barrage could provide around 5% of Britain’s energy. Environmentalists fear irreparable damage to marshes and mudflats, but the Government is known to prefer the barrage to other, smaller options. The decision it takes next year is sure to be eagerly watched in Scotland.

Somewhat overshadowed by the Severn plan is Wave Hub, a project to build a wave-power station 10 miles off St Ives, on Cornwall’s north coast, using both Pelamis and a sea-bed device developed by ORECon of Plymouth. An application to create a safety area around it has just been submitted, part of the meticulous planning that precedes any marine trial.

“We have to have environmentalists looking at the impact on fisheries, flora and fauna,” says McAdam. “And we have to be completely open with the communities we’re going into. But most people realise that climate change and energy security are real things. We want to minimalise our environmental impact and give the country a means of isolating itself from the volatility of oil and gas.”

In theory, marine energy could generate a fifth of the UK’s electricity needs, but that would require a multitude of stations. Bill Banks believes nuclear power will be needed. “But we also need a variety of renewables,” he says. “Marine will take its place along with bio, hydro and wind energy. It’s available, it’s there at the moment, and if we get our act together I think we can lead Europe. We need a synergy of activity.”

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JENNY HAWORTH, Scotman.com, February 12, 2009

na910MORE than three dozen energy companies from across the world are hoping to install wave energy devices in a stretch of sea off the north of Scotland. The renewable energy firms all have their sights on the Pentland Firth, which is considered one of the best locations in the world for generating electricity from the power of the tides.

Yesterday, the Crown Estate, which owns the seabed and will authorize any offshore  wave energy project, announced it had invited 38 companies to submit detailed plans for schemes in the Pentland Firth.

This is the first stretch of water off the UK to be opened up for development of marine renewables, meaning successful companies will be building among the first marine wave energy projects in the world.

Each company hopes to install dozens, or even hundreds of wave energy devices, such as tidal turbines, in the ocean.

Alex Salmond, the First Minister, hopes it will help Scotland become a world leader in renewable energy, saying “the fact that so many companies have already registered their interest in developing wave and tidal energy projects in the Pentland Firth and surrounding waters is extremely encouraging.”

“The Scottish Government has recently launched the world’s greatest-ever single prize for innovation in marine energy, the £10 million Saltire Prize, and the opening of the Pentland Firth for development is a timely and crucial move.”

The Crown Estate invited initial expressions of interest in the Pentland Firth from renewables firms in November 2008. A spokeswoman said she could not reveal how many companies had shown an interest because of competition rules, but she confirmed 38 firms would be invited to the next stage – to tender for sites in the Pentland Firth.

They must now submit detailed applications, spelling out how many devices they want to install in the water, by the end of May.

The Crown Estate will decide which are suitable, and the companies will then have to apply for planning permission from the Scottish Government.

Calum Duncan, Scottish conservation manager for the Marine Conservation Society, welcomed renewable technologies, but said the possible impact of the devices on sensitive seabed habitats must be considered, including the likely affect on mussel beds and feeding areas for fish, basking sharks and seabirds.

Liam McArthur, the Liberal Democrat energy spokesperson and MSP for Orkney, also welcomed the strong interest but had reservations. “This energetic stretch of water will be a challenging resource to tame,” he said.

“We still know relatively little about the Pentland Firth and what will happen when we start putting devices in the water there.

“While the Pentland Firth is often described as the Saudi Arabia of tidal power, the challenges it presents also make it the Mount Everest.”

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RenewableEnergyWorld.com, January 27, 2009 

One Choice

One Option on the Shortlist

A shortlist of proposed plans to generate electricity from the power of the tides in the Severn estuary has been unveiled by the UK Department of Energy and Climate Change.

UK Energy and Climate Change Secretary Ed Miliband has also announced £500,000 [US $702,000] of new funding to further develop early-stage technologies like tidal reefs and fences. The progress of these technologies will be considered before decisions are taken whether to go ahead with a Severn tidal power scheme.

The tides in the Severn estuary are the second highest in the world. The largest proposal being taken forward has the potential to generate nearly 5% of the UK’s electricity from this domestic, low carbon and sustainable source.

Over the past year, the Government-led feasibility study has been investigating a list of ten options, gathering information on the costs, benefits and environmental challenges of using the estuary to generate power.

The proposed shortlist is includes:       

  • Cardiff Weston Barrage: A barrage crossing the Severn estuary from Brean Down, near Weston super Mare to Lavernock Point, near Cardiff. Its estimated capacity is over 8.6 gigawatts (GW).
  • Shoots Barrage: Further upstream of the Cardiff Weston scheme. Capacity of 1.05 GW, similar to a large fossil fuel plant.
  • Beachley Barrage: The smallest barrage on the proposed shortlist, just above the Wye River. It could generate 625 MW.
  • Bridgwater Bay Lagoon: Lagoons are radical new proposals which impound a section of the estuary without damming it. This plan is sited on the English shore between east of Hinkley Point and Weston super Mare. It could generate 1.36 GW.
  • Fleming Lagoon: An impoundment on the Welsh shore of the estuary between Newport and the Severn road crossings. It too could generate 1.36 GW.The proposed shortlist will now be subject to a three month public consultation which begins this week.

“Fighting climate change is the biggest long term challenge we face and we must look to use the UK’s own natural resources to generate clean, green electricity. The Severn estuary has massive potential to help achieve our climate change and renewable energy targets. We want to see how that potential compares against the other options for meeting our goals,” said UK Energy and Climate Change Secretary Ed Miliband.

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ALOK JHA, Guardian UK, January 5, 2009

Tidal Energy's DeltaStream

Tidal Energy's DeltaStream

Propellers on ships have been tried and tested for centuries in the rough and unforgiving environment of the sea: now this long-proven technology will be used in reverse to harness clean energy from the UK’s powerful tides.

The tides that surge around the UK’s coasts could provide up to a quarter of the nation’s electricity, without any carbon emissions. But life in the stormy seas is harsh and existing equipment – long-bladed underwater wind turbines – is prone to failure.  A Welsh renewable energy company has teamed up with ship propulsion experts to design a new marine turbine which they believe is far more robust.

Cardiff-based Tidal Energy Limited will test a 1MW tidal turbine off the Pembrokeshire coast at Ramsey Sound, big enough to supply around 1,000 homes. Their DeltaStream device, invented by marine engineer Richard Ayre while he was installing buoys in the marine nature reserve near Pembrokeshire, will be the first tidal device in Wales and become fully operational in 2010.

To ensure the propeller and electricity generation systems were as tough as possible, the tidal turbine’s designers worked with Converteam, a company renowned for designing propulsion systems for ships. “They’ve put them on the bottom of the Queen Mary … and done work for highly efficient destroyers, which is exactly the same technology that we’re looking at here,” said Chris Williams, development director of DeltaStream.

DeltaStream’s propellers work in reverse to a ship’s propulsion system – the water turns the blades to generate electricity – but the underlying connections between blades and power systems are identical to those on the ship.

Tidal streams are seen as a plentiful and predictable supply of clean energy, as the UK tries to reduce its greenhouse gas emissions. Conservative estimates suggest there is at least 5GW of power, but there could be as much as 15GW – 25% of current national demand.

A single DeltaStream unit has three propeller-driven generators that sit on a triangular frame. It weighs 250 tonnes, but is relatively light compared with other tidal systems which can be several times heavier. The unit is simple to install and can be used in closely packed units at depths of at least 20m. Unlike other tidal turbine systems, which must be anchored to the sea floor using piles bored into the seabed, DeltaStream’s triangular structure simply sits on the sea floor.

Duncan Ayling, head of offshore at the British Wind Energy Association and a former UK government adviser on marine energy, said that one of the biggest issues facing all tidal-stream developers is ease of installation and maintenance of their underwater device. “Anything you put under the water becomes expensive to get to and service. The really good bit of the DeltaStream is that they can just plonk it in the water and it just sits there.”

Another issue that has plagued proposed tidal projects is concern that the whirling blades could kill marine life. But Williams said: “The blades themselves are thick and slow moving in comparison to other devices, so minimising the chance of impact on marine life.”

The device also has a fail-safe feature when the water currents become too powerful and threaten to destroy the turbines by dragging them across the sea floor – the propellers automatically tilt their orientation to shed the extra energy.

Pembrokeshire businessman and sustainability consultant Andy Middleton said: “People are increasingly recognising how serious global warming really is, and in St David’s we are keen to embrace our responsibility to minimise climate change. DeltaStream is developing into a perfect example of the technology that fills the need for green energy and has the added benefit of being invisible and reliable.”

The country’s first experimental tidal turbine began generating electricity in Strangford Lough, Northern Ireland last year, built by Bristol-based company Marine Current Turbines. SeaGen began at about 150kW, enough for around 100 homes, but has now reached 1,200kW in testing. It had a setback early in its test phase, with the tidal streams breaking one of the blades in July.

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BBC News, December 18, 2008

_45310426_43017507A tidal turbine near the mouth of Strangford Lough has begun producing electricity at full capacity for the first time.  The SeaGen system now generates 1.2MW, the highest level of power produced by a tidal stream system anywhere in the world.

The system works like an “underwater windmill” but with rotors driven by tidal currents rather than the wind.

It has been undergoing commissioning trials since May.

SeaGen will now move towards full-operating mode for periods of up to 22 hours a day, with regular inspections and performance testing carried out.

The power generated by the system is being purchased by Irish energy company, ESB Independent, for its customers in Northern Ireland and the Republic.

The turbine has the capacity to generate power to meet the average electricity needs of around 1000 homes.

Martin Wright, managing director of SeaGen developers, Marine Current Turbines, said that having the system generating at full power was an important milestone.

“It demonstrates, for the first time, the commercial potential of tidal energy as a viable alternative source of renewable energy,” he said.

“As the first mover in tidal stream turbine development, we have a significant technical lead over all rival tidal technologies that are under development.

“There are no other tidal turbines of truly commercial scale; all the competitive systems so far tested at sea are quite small, most being less than 10% the rotor area of SeaGen.”

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Guardian.co.uk, December 3, 2008

wave-ocean-blue-sea-water-white-foam-photoWay back in Napoleonic Paris, a Monsieur Girard had a novel idea about energy: power from the sea. In 1799, Girard obtained a patent for a machine he and his son had designed to mechanically capture the energy in ocean waves. Wave power could be used, they figured, to run pumps and sawmills and the like.

These inventors would disappear into the mists of history, and fossil fuel would instead provide an industrializing world with almost all its energy for the next two centuries. But Girard et fils were onto something, say a growing number of modern-day inventors, engineers, and researchers. The heave of waves and the tug of tides, they say, are about to begin playing a significant role in the world’s energy future.

In the first commercial scale signal of that, last October a trio of articulated, cylinder-shaped electricity generators began undulating in the waves off the coast of Portugal. The devices look like mechanical sea snakes. (In fact, their manufacturer, Scotland’s Pelamis Wave Power Ltd., takes its name from a mythical ancient Greek sea serpent.) Each Pelamis device consists of four independently hinged segments. The segments capture wave energy like the handle of an old fashioned water pump captures the energy of a human arm: as waves rock the segments to and fro, they pump a hydraulic fluid (biodegradable, in case of spills) powerfully through a turbine, spinning it to generate up to 750,000 watts of electricity per unit. Assuming the devices continue to perform well, Portuguese utility Energis expects to soon purchase another 28 more of the generators.

The completed “wave farm” would feed its collective power onto a single high voltage sea-floor cable, adding to the Portuguese grid about 21 megawatts of electricity. That’s enough to power about 15,000 homes.

In a world where a single major coal or nuclear plant can produce more than 1,000 megawatts of electricity, it’s a modest start. But from New York’s East River to the offshore waters of South Korea, a host of other projects are in earlier stages of testing. Some, like Pelamis, rely on the motion of waves. Others operate like underwater windmills, tapping the power of the tides.

Ocean-powered technologies are in their infancy, still technologically well behind such energy alternatives as wind and solar. Necessarily designed to operate in an inherently harsh environment, the technologies remain largely unproven and — unless subsidized by governments — expensive. (Portugal is heavily subsidizing the Pelamis project, with an eye to becoming a major European exporter of clean green power in the future.) Little is known about the effects that large wave or tide farms might have on marine ecosystems in general.

Despite the uncertainties, however, proponents say the potential advantages are too striking to ignore. Eight hundred times denser than air, moving water packs a huge energy wallop. Like solar and wind, power from moving seas is free and clean. But sea power is more predictable than either wind or solar. Waves begin forming thousands of miles from coastlines and days in advance; tides rise and fall as dependably as the cycles of the moon. That predictability makes it easier to match supply with demand.

Roger Bedard, who leads ocean energy research at the U.S. utility-funded Electric Power Research Institute (EPRI) in Palo Alto, says there’s plenty of reason for optimism about the future of what he calls “hydrodynamic” power. Within a decade, he says, the U.S. could realistically meet as much as 10% of its electricity needs from hydrodynamic power. As a point of reference, that’s about half of the electricity the U.S. produces with nuclear power today. Although he acknowledges that initial sea-powered generation projects are going to be expensive, Bedard believes that as experience grows and economies of manufacturing scale kick in, hydrodynamic power will follow the same path toward falling costs and improving technologies as other alternatives.

“Look at wind,” he says. “A kilowatt hour from wind cost fifty cents in the 1980s. Now it’s about seven cents.” (That’s about the same as producing electricity with natural gas, and only about three cents more than coal, the cheapest — and dirtiest — U.S. energy choice. Any future tax on carbon emissions could narrow that gap even more, as would additional clean-power subsidies.)

For some nations, wave and tide power could pack an even bigger punch. Estimates suggest, for instance, that the choppy seas surrounding the United Kingdom could deliver as much as 25% of its electricity. British alternative energy analyst Thomas W. Thorpe believes that on a worldwide basis, waves alone could produce as much as 2,000 terawatt hours of electricity, as much as all the planet’s major hydroelectric plants generate today.

Although none are as far along as Pelamis, most competing wave-power technologies rely not on the undulations of mechanical serpents, but instead on the power captured by the vertical bobbing of large buoys in sea swells. Ocean Power Technologies (OPT), based in New Jersey, drives the generators in its PowerBuoy with a straightforward mechanical piston. A stationary section of the mostly submerged, 90-foot buoy is anchored to the ocean floor; a second section simply moves up and down with the movement of sea swells, driving pistons that in turn drive an electrical generator. The Archimedes Wave Swing, a buoy-based system developed by Scotland’s AWS Ocean Energy, harnesses the up-and-down energy of waves by pumping air to spin its turbines. Vancouver-based Finavera Renewables uses seawater as its turbine-driving hydraulic fluid.

Although Pelamis beat all of these companies out of the commercialization gate, OPT appears to be right behind, with plans to install North America’s first commercial-scale wave power array of buoys off the coast of Oregon as early as next year. That array — occupying one square-mile of ocean and, like other wave power installations, located far from shipping lanes — would initially produce 2 megawatts of power. OPT also announced last September an agreement to install a 1.4-megawatt array off the coast of Spain. An Australian subsidiary is in a joint venture to develop a 10-megawatt wave farm off the coast of Australia.

Meanwhile, Pelamis Wave Power plans to install more of its mechanical serpents — three megawatts of generating capacity off the coast of northwest Scotland, and another five-megawatt array off Britain’s Cornwall coast.

The Cornwall installation will be one of four wave power facilities plugged into a single, 20-megawatt underwater transformer at a site called “Wave Hub.” Essentially a giant, underwater version of a socket that each developer can plug into, Wave Hub — which will be connected by undersea cable to the land-based grid — was designed as a tryout site for competing technologies. OPT has won another of the four Wave Hub berths for its buoy-based system.

Other innovators are trying to harness the power of ocean or estuarine tides. Notably, in 2007, Virginia’s Verdant Power installed on the floor of New York’s East River six turbines that look, and function, much like stubby, submerged windmills, their blades — which are 16 feet in diameter — turning at a peak rate of 32 revolutions per minute. The East River is actually a salty and powerful tidal straight that connects Long Island Sound with the Atlantic Ocean. Although the “underwater windmills” began pumping out electricity immediately, the trial has been a halting one. The strong tides quickly broke apart the turbines’ first- (fiberglass and steel) and second- (aluminum and magnesium) generation blades, dislodging mounting bolts for good measure.

Undeterred, in September Verdant Power began testing new blades made of a stronger aluminum alloy. If it can overcome the equipment-durability problems, the company hopes to install as many as 300 of its turbines in the East River, enough to power 10,000 New York homes.

A scattering of similar prototype “underwater windmill” projects have been installed at tidal sites in Norway, Northern Ireland, and South Korea. (In addition, interest in moving into freshwater sites is growing. Verdant itself hopes to install its turbines on the St. Lawrence River. At least one other company, Free Flow Power of Massachusetts, has obtained Federal Energy Regulatory Commission permits to conduct preliminary studies on an array of sites on the Mississippi River south of St. Louis.)

The environmental benefits of hydrodynamic power seem obvious: no carbon dioxide or any other emissions associated with fossil-fuel-based generation. No oil spills or nuclear waste. And for those who object to wind farms for aesthetic reasons, low-profile wave farms are invisible from distant land; tidal windmill-style turbines operate submerged until raised for maintenance.

There are, however, environmental risks associated with these technologies.

New York state regulators required Verdant Power to monitor effects of their its turbines on fish and wildlife. So far, sensors show that fish and water birds are having no trouble avoiding the blades, which rotate at a relatively leisurely 32 maximum revolutions per minute. In fact the company’s sensors have shown that fish tend to seek shelter behind rocks around the channel’s banks and stay out of the central channel entirely when tides are strongest.

But a host of other questions about environment effects remain unanswered. Will high-voltage cables stretching across the sea from wave farms somehow harm marine ecosystems? Will arrays of hundreds of buoys or mechanical serpents interfere with ocean fish movement or whale migrations? What effect will soaking up large amounts of wave energy have on shoreline organisms and ecosystems?

“Environmental effects are the greatest questions right now,” EPRI’s Bedard says, “because there just aren’t any big hydrodynamic projects in the world.”

Projects will probably have to be limited in size and number to protect the environment, he says – that’s a big part of the reason he limits his “realistic” U.S. estimate to 10% of current generation capacity. But the only way to get definitive answers on environmental impact might be to run the actual experiment — that is, to begin building the water-powered facilities, and then monitor the environment for effects.

Bedard suggests that the way to get definitive answers will be to build carefully on a model like Verdant’s: “Start very small. Monitor carefully. Build it a little bigger and monitor some more. I’d like to see it developed in an adaptive way.”

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JAMES OWEN, National Geographic News, December 2, 2008

The race is officially on for a U.S. $15 million (10 million Euro) prize for harnessing the power of the oceans.

The winning marine renewable energy innovation would provide a serious energy alternative to burning fossil fuels, which contribute to global warming.

Details of the Saltire Prize Challenge were announced Tuesday in Edinburgh by Scotland’s First Minister, Alex Salmond.

The award will go to the team that “successfully demonstrates—in Scottish waters—the best commercially viable wave or tidal technology capable of providing electricity to thousands of homes.”

The winning team must supply this electricity using only the power of the sea for a continuous two-year period.

“It is Scotland’s energy challenge to the world—a challenge to the brightest and best minds worldwide to unleash their talents and push the frontiers of innovation in green marine energy,” Salmond said.

“The Saltire Prize has the potential to unlock Scotland’s vast marine energy wealth, putting our nation at the very forefront of the battle against climate change.”

The prize, named after the cross of St. Andrew on the Scottish national flag, was inspired by other innovation competitions such as the U.S. $10 million Ansari X Prize.

That contest led to the first private spacecraft launch in 2004.

“Saudi Arabia of Ocean Energy”

Scotland boasts a quarter of Europe’s tidal power potential, according to Salmond.

He described the Pentland Firth, a region between Scotland’s north coast and the Orkney Islands, as the “Saudi Arabia of renewable marine energy.”

Scotland aims to meet 50% of its electricity demand from renewable resources by 2020.

There’s also huge potential for ocean energy globally, said prize committee member Terry Garcia, executive vice president for mission programs for the National Geographic Society. “It’s not going to be the sole solution to our energy needs,” Garcia said, but “this will be one of the important pieces of the puzzle.” The main purpose of the competition is to act as a catalyst for innovation, Garcia added.

“It’s both about making marine energy economically viable and being able to produce it in a sustained way on a large scale,” he said.

Wave and Tidal Power

The two major types of ocean energy are wave and tidal energy.

Wave energy technology involves floating modules with internal generators, which produce electricity as they twist about on the sea surface.

Tidal energy harnesses tidal currents with arrays of underwater turbines similar to those that propel wind farms.

Tidal ranks among the most reliable renewable energies because tides are highly predictable, said AbuBakr Bahaj, head of the University of Southampton’s Sustainable Energy Research Group in the U.K.

“But wave energy is driven by wind, which is notoriously difficult to predict,” he said.

Even so, wave power may have the higher electricity-generating potential.

In Britain, for instance, it’s estimated that wave power could potentially provide 20% of the country’s total electricity supply, against 5-10%for tidal power, Bahaj said.

The scientist says the main technical challenge is to create reliable power installations that can operate in difficult marine environments for five to ten years without maintenance.

“You also need to have multiple devices working together at each site,” he said.

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KEVIN FERGUSON, The Information Week, November 24, 2008

1739725132_460c52d56dWhere is President-elect Barack Obama headed with environmental protection and renewable energy? The answer lies not so much in the encouraging but ultimately self-serving video posted on the transition team’s Web site, but rather on links elsewhere on the page. In particular, look at the appointment of senior transition official Rose McKinney-James as FERC Review Team Lead.

Unless you live in California or Nevada, you may not be familiar with the Federal Energy Regulatory Commission.  FERC — a relatively tiny agency that requested only $273.4 million and 1,465 full-time employees in its FY 2009 budget — regulates the country’s natural gas industry, hydroelectric projects, oil pipelines, and wholesale rates for electricity. You may recall that public advocacy groups excoriated FERC for its role in the deregulation of the wholesale electricity market in California and subsequent power crisis in 2000 and 2001.

So, what’s the significance of this recent appointment? McKinney-James, managing principal of Energy Works Consulting, has been championing renewable energy for decades, as the president and CEO of the public Corporation for Solar Technology and Renewable Resources (CSTRR), chair of the Nevada Renewable Energy Task Force, commissioner with the Nevada Public Service Commission, and other pubic posts.

Her efforts also have included renewable energy advocacy in the private sector — and in some rather unexpected places. The most visible of those places is MGM Mirage’s  Protech CityCenter in Las Vegas. McKinney-James sits on the MGM board.

The $7 billion development was recently awarded a Leadership in Energy and Environmental Design (LEED) certification by the U.S. Green Building Council. Project CityCenter includes a 4,000-room hotel-casino, two 400-room boutique hotels, more than 500,000 square feet of retail space, and 2,900 residential units on 66 acres between the Bellagio and Monte Carlo.

Perhaps McKinney-James can accelerate what has been a slow accommodation of renewable energy sources into FERC’s mix.

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MICHELLE MA, Seattle Times, November 17, 2008

What started out as a mad dash to extract energy from the ocean’s waves and tides has slowed to a marathoner’s pace — complete with a few water breaks and sprained ankles along the way.

In the past three years, more than 100 preliminary permits have been issued nationally for wave and tidal energy projects, and nearly 100 more are pending approval. But only one has won a license to operate — a small wave energy development off Washington’s northwest coast.

That project is still awaiting state and federal permits, and its British Columbia-based developer, Finavera Renewables, doesn’t know when the first devices will go in the water. It doesn’t help that a wave power buoy the company was testing off the Oregon coast unexpectedly sank last year.

Tapping the power of waves and tidal currents to generate electricity is promoted as one of many promising alternatives to the fossil fuels that contribute to global warming.

But no one knows exactly how the technologies will behave in the water, whether animals will get hurt, or if costs will pencil out. The permitting process is expensive and cumbersome, and no set method exists for getting projects up and running.

“The industry is really young, and everything is hodgepodged right now,” said Jim Thomson, an oceanographer at the University of Washington’s Applied Physics Lab who is involved in tidal research.

A new report that collected findings from dozens of scientists raises concerns about the impact wave energy developments could have on the ocean and its critters. Wave energy buoys could alter the food chain or disrupt migrations, the report says.

Still, developers, regulators and researchers are moving forward. A 2.25-megawatt project off the coast of Portugal went on line this fall, becoming the world’s first commercial wave energy development in operation. It can supply 1,500 households with electricity.

The first commercial wave energy park in the U.S. could go in off Reedsport, Ore., within the next two years.

Tidal energy has yet to go commercial, but devices have been tested in Ireland and Canada. Turbines have been placed in New York’s East River, and a demonstration project is planned for the Bay of Fundy off Northeastern U.S.

In the Northwest, the Snohomish County Public Utility District (PUD) has narrowed its search for tidal power sites in Puget Sound, although the PUD doesn’t expect to have a test project in the water for another two years.

Race to develop

Dozens of developers have staked claim to plots in the ocean and in waterways that could provide wave and tidal energy. But despite the jostle for space, getting projects off dry land has proved difficult.

Wave power generators use the up-and-down motion of the ocean’s swells to produce electricity. Tidal generators act like underwater windmills, spinning as the tides move in and out.

To get small projects in the water quicker federal regulators recently created a five-year pilot license for tidal and wave developments. That’s meant to help developers gather data they need to launch future projects, said Federal Energy Regulatory Commission spokeswoman Celeste Miller.

Yet even with a more streamlined process, no one has applied for the pilot license, Miller said. Finavera received its license for the 1-megawatt Makah Bay wave project before this option became available.

Given the unknowns in a young industry, it’s not surprising projects are taking longer than some developers would like, said Myke Clark, senior vice president of business development for Finavera.

His company encountered another hurdle when Pacific Gas and Electric’s agreement to buy power from a planned Finavera wave energy project off California was rejected last month by the state’s Public Utilities Commission.

Regulators said the rates were too high and the buoy technology not yet ready.

Clark said the decision wouldn’t affect Finavera’s Makah Bay project.

Research under way

Researchers from the University of Washington and Oregon State University hope that a new national marine renewable energy research center in the Northwest will help answer questions about tidal and wave energy.

A federal grant provides $1.25 million annually for up to five years. The UW will continue research on tidal energy in Puget Sound, while OSU will focus on wave energy.

“The feeling is that a lot of questions being asked now are only questions that can be answered with a responsible pilot [project],” said Brian Polagye, who is pursuing his doctorate in mechanical engineering at the UW.

Locally, researchers want to see where marine life in Puget Sound congregates and to create a standard way to evaluate sites around the country to determine which would be good candidates for tidal energy projects.

Admiralty Inlet, between Whidbey Island and Port Townsend, is the likely spot for the Snohomish County PUD’s small test project set to launch at least two years from now, said Craig Collar, the PUD’s senior manager of energy resource development.

The inlet’s tides are strong, and the area is large enough to accommodate a tidal project without interfering with other activities such as diving and ferry traffic.

Finavera wants to install four wave energy buoys in Makah Bay in the Olympic Coast National Marine Sanctuary to test its technology. Developers also plan to monitor the project for effects on wildlife and shoreline habitat, keeping an eye on federally listed species such as the marbled murrelet, a small bird that dives for food.

Finavera doesn’t intend to continue the project after its five-year license expires. Still, if the company can negotiate a purchasing agreement with the Clallam County Public Utility District, homes in the area could use the wave generated power while the project is in the water, Clark said.

The Makah Nation wants to see what effect the project might have on the environment before deciding whether wave energy is a viable long-term option, said Ryland Bowechop, tourism and economic-development planner for the tribe.

The buoys would sit just offshore from the tribal headquarters in Neah Bay.

“We are always concerned because our livelihood is the ocean,” Bowechop said.

Concerns linger

The environmental effects of wave and tidal energy are largely unknown and require more studies, dozens of scientists concluded after meeting a year ago at OSU’s Hatfield Marine Science Center in Newport, Ore.

The group was concerned that electromagnetic cables on the ocean floor could affect sea life, and that buoys could interfere with whale and fish migration.

Large buoys might actually attract more fish, but the marine ecosystem could be altered if more predators move in. Buoys also could disrupt natural currents and change how sediment is moved. Shorelines might be affected as energy is taken from the waves.

Even if environmental concerns are checked, costs to extract the power remain high. Wave energy costs at least 20 cents per kilowatt hour to generate, compared with 4 cents per kilowatt hour for wind power, said Annette von Jouanne, leader of OSU’s wave energy program. Wind energy used to be much more expensive 20 years ago.

In comparison, coal-generated power costs about 5 cents per kilowatt hour, and power from dams can be as low as 3 cents, said Roger Bedard, ocean energy leader with the nonprofit Electric Power Research Institute.

Tidal energy costs are harder to determine because there aren’t any projects trying to sell electricity, Bedard said.

Fishermen have their own worries. They fear that wave and tidal projects could further reduce access to fishing grounds, said Dale Beasley, a commercial fisherman in Ilwaco, Pacific County, and president of the Columbia River Crab Fisherman’s Association.

“There’s so many things coming at the ocean right now,” he said.

Beasley says the industry wants a say in how wave and tidal energy projects are developed.

“Coastal communities are going to have to figure out a way to deal with this, and if they don’t, the character of the coast will change dramatically,” he said.

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TERRY DILLMAN, South Lincoln County News, September 23, 2008

Oregon’s emergence as a national leader in developing wave energy technology crested Thursday, when the U.S. Department of Energy (DOE) announced grant support to establish the Northwest National Marine Renewable Energy Center at Oregon State University’s Hatfield Marine Science Center (HMSC) in Newport.

The agency selected 14 research teams to receive as much as $7.3 million -representing a cost-shared value of more than $18 million – for projects to “advance commercial viability, cost-competitiveness, and market acceptance of new technologies that can harness renewable energy from oceans and rivers.” It’s part of the federal Advanced Energy Initiative designed to dramatically boost clean-energy research funding to develop cleaner, reliable alternative energy sources that cost less. The Energy Independence and Security Act (EISA) signed into law in December 2007 authorizes DOE to establish a program of research, development, demonstration, and commercial application to expand marine and hydrokinetic renewable energy production.

“Wave, tidal, and current-driven hydro power is an important clean, natural, and domestic energy source that will promote energy security, and reduce greenhouse gas emissions,” John Mizroch, acting assistant secretary of energy efficiency and renewable energy, noted in announcing the selections.

A merit review committee of national and international water power experts made the selections. Two awards of up to $1.25 million in annual funding, renewable for up to five years, went to establishing marine energy centers.

One went to the University of Hawaii in Honolulu for the National Renewable Marine Energy Center.

The other went to OSU and the University of Washington to establish the Northwest National Marine Renewable Energy Center at HMSC, with “a full range of capabilities to support wave and tidal energy development” for the nation. DOE officials want the center to “facilitate commercialization, inform regulatory and policy decisions, and close key gaps in understanding.”

The federal grant will add to funding from the Oregon legislature, OSU, the Oregon Wave Energy Trust (OWET), the University of Washington and other sources to bring in $13.5 million in five years to – according to Robert Paasch, the interim program director for the new center – “help move the generation of energy from waves, ocean currents and tides from the laboratory to part of the nation’s alternative energy future.”

The main effort is to build a floating “berth” to test wave energy technology off the Oregon coast near Newport, as well as fund extensive environmental impact studies, community outreach, and other initiatives.

“This is just the beginning,” Paasch added. “There’s still a lot of work to do on the technology, testing, and environmental studies. But we have no doubt that this technology will work, that wave energy can become an important contributor to energy independence for the United States.”

Oregon can now lead those efforts, thanks to involvement by numerous partners.

The state legislature committed $3 million in capital funding to help create the new wave energy test center.

OWET – a private, not-for-profit organization founded in 2007 and funded by Oregon Inc. to be an integral part of the state’s effort to become the leader in renewable wave energy development – has provided $250,000 in funding, and is working to coordinate support from government agencies, private industry, fishing, environmental, and community groups.

OWET’s goal is to have ocean wave energy producing at least 500 megawatts of energy by 2025 for Oregon consumption.

The University of Washington has committed funding support and will take the lead role in innovative research on tidal and ocean current energy. The National Renewable Energy Center in Golden, Colo., will support studies on how to integrate wave energy into the larger power grid, and help it take its place next to other alternative energy sources, such as wind and solar.

Lincoln County officials immersed themselves in the effort from the outset. OSU’s wave energy test site is off county shores, and groups such as the Newport-based FINE – Fisherman Involved in Natural Energy – are active in providing input and advice from coastal constituencies.

“Oregon is now the unquestioned national leader in marine renewable energy,” Paasch said. “But as this technology is still in its infancy, we want to get things right the first time. We need extensive research on environmental impacts, we need to work with community groups and fishermen, and we need our decisions to be based on sound science as we move forward.”

OSU’s College of Engineering, College of Oceanic and Atmospheric Sciences and Hatfield Marine Science Center will lead technology development, as well as diverse research programs on possible environmental impacts on the wave resource, shores, marine mammals and other marine life.

Construction of the new floating test berth should begin in 2010, Paasch said, after design, engineering work and permits have been completed. The facility will open on a fee basis to private industry groups that want to test their technology, and will provide detailed power analysis, as well as a method to dissipate the power.

“When complete, we’ll be able to test devices, see exactly how much power they generate and be able to assess their environmental impact, using technologies such as the OSU Marine Radar Wave Imaging System and on-site wave sensors,” Paasch

OSU will also continue its own research on wave energy technology led by Annette von Jouanne, professor of electrical engineering.

The university is working closely with private industry partners, recently finished a linear test bed to do preliminary testing of new technology on the OSU campus, and will test prototypes that OSU researchers consider as having the best combination of power production, efficiency and durability. In 2007, the university hosted a workshop to begin looking at the potential ecological implications of establishing wave energy parks along the West Coast. On-going research will continue to ponder that and many other questions.  Much of that research will take place at HMSC.

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ISABEL ORDONEZ, Dow Jones News Service, October 6, 2008

Surfers aren’t the only ones itching to jump in the water and catch some big waves.

Dozens of companies, from oil giant Chevron Corp. to smaller firms like Ocean Power Technologies Inc., have invested in or are evaluating the potential of technology designed to harness electrical energy from waves, tides and currents.

Ocean Power, of Pennington, N.J., and Verdant Power Inc., of New York, are among the firms that already have built or plan to build wave and tidal power stations in oceans or adjacent waters. Others, such as Chevron, are seeking government approval to study the feasibility of such projects. All are in a race to harness what some scientists contend is among the nation’s largest unexploited sources of renewable energy.

“Chevron is monitoring ocean energy technology and considering how it might be integrated into our operations,” says Kim Copelin, a spokeswoman for the San Ramon, Calif., company, which is seeking a permit from the Federal Regulatory Energy Commission to start researching a possible tidal-power project in Alaska’s Cook Inlet.

These projects represent a rebirth of interest in the ocean and other waters as a source of energy, which intensified during the 1970s oil crises but fizzled in the 1980s when the price of oil dropped. Now, with concerns growing about global climate change, foreign oil dependency and rising commodity prices, companies and governments are taking another look.

Ocean-energy technology is in its infancy, and big hurdles to its widespread use remain. Among them: figuring out how to economically produce power on a large scale without harming marine life, and navigating a permitting process that companies say is lengthy and cumbersome but that some government agencies say is necessary to protect the environment.

Despite the hurdles, supporters believe there is an abundance of energy sitting off the U.S. coast just waiting to be tapped. While the amount of energy currently being produced by ocean-energy projects is minuscule, the Electric Power Research Institute — the research arm of U.S. utility companies — estimates that oceans eventually could supply about 10% of the electricity consumed in the U.S.

“Oceans are an enormous resource that should be seriously considered as part of the U.S. renewable energy portfolio,” says Sean O’Neill, president of the Ocean Renewable Energy Coalition, a national trade organization. Oceans “have waves, tides, currents, even offshore winds that don’t need to compete for precious land resources to generate plenty of electricity.”

Predictability of Tides

Companies are using a variety of devices to create electricity from moving water.

Ocean Power, for example, uses a network of buoys. The up-and-down movement of the ocean’s waves is converted into hydraulic pressure by pistons and cylinders located inside the buoys. That pressure spins a turbine, which turns a generator. The resulting electricity is sent ashore via an underwater cable. The company has a contract with the U.S. Navy to install and test its devices off the Marine Corps base at Kaneohe Bay, Hawaii. It also is working with a utility company in California and Oregon to build four wave-power stations, pending federal approvals.

verdantVerdant Power, meanwhile, produces power for a supermarket and parking lot using six underwater turbines in New York’s East River. The movement of water from the river’s tides turns blades on the turbines, creating a rotary motion that runs a generator. The company says it has a list of customers waiting for it to get the necessary approval to start generating electricity on a larger scale.

The prime territory in the U.S. to harvest energy from wave power is in the Pacific Ocean, off the coasts of Hawaii, Alaska, Oregon, Washington and northern and central California. The optimum spot for tapping into ocean currents, which are steady flows of water going in a prevailing direction, is off the shores of south Florida, while parts of the Alaska coastline, including the upper Cook Inlet around Anchorage, have some of the strongest tides in the world. The edges of Maine, New York, San Francisco and Washington state’s Puget Sound also look to be ideal for tidal energy, researchers say.

Tidal energy is drawing special interest because, though intermittent, it is more predictable than wind, solar or wave energy. While those energy sources rely on the weather, tides depend on the position of the sun, Earth and moon and gravitational forces that can be accurately predicted years in advance, says Roger Bedard, ocean energy leader at the nonprofit Electric Power Research Institute.

Regulatory Jockeying

New York, Maine, Alaska and other coastal states are investing in ocean energy projects, as is the U.S. Department of Energy, which spent $7.5 million in fiscal 2008 and could spend as much as $35 million in fiscal 2009 to help advance the viability and cost competitiveness of ocean water driven power systems.

“We need everything we can get to try to address energy supply issues,” says Steven Chalk, deputy assistant secretary for renewable energy at the Department of Energy. “If we have a true supply diversification, we will be less vulnerable to, say, rising oil prices.”

But proponents of ocean energy say private investment is being deterred by what they call an overly lengthy and complicated permitting process. Companies sometimes need more than 20 local, state and federal regulatory permits to start ocean energy research, says Mr. O’Neill of the Ocean Renewable Energy Coalition. As an example, Verdant Energy says it has spent more than $2 million on environmental research and waited more than five years to get to the final stages of obtaining the permits it needs to install more underwater turbines and produce electricity on a larger scale.

“In a perfect world, the U.S. will have a fast way to deal with new emerging technologies that allow companies to get into the water and start testing how efficient the equipment is and to measure the environmental impacts,” says Mr. O’Neill. “But that is just a dream.”

The projects facing the biggest logjams are those proposed for federal waters on the outer continental shelf, which generally begins three miles beyond the U.S. shoreline. Companies interested in generating energy from that part of the ocean need approval from both the Federal Energy Regulatory Commission — the U.S. agency that regulates interstate natural gas and electricity transactions — and the U.S. Minerals Management Service, a branch of the Interior Department that oversees offshore energy development.

An effort to end what many companies say is a jurisdictional overlap was unsuccessful, and last month, the Minerals Management Service unveiled a set of proposed permitting rules, including environmental regulations, that it expects to have in place by later this year.

Mark Robinson, director of the office of energy projects at FERC, says his agency believes the Minerals Management Service’s proposed process is too long and costly and “will work to the disadvantage of an industry” that is trying to get on its feet.

The Minerals Management Service says that it is still evaluating comments on its proposed rules but that it has two main responsibilities when it comes to offshore energy production: securing the nation’s energy resources and protecting the environment. “We take both very seriously,” says David Smith, the agency’s deputy chief of public affairs. “We work to try to find that balance.”

In the meantime, the Minerals Management Service is granting interim leases that allow companies to test the energy potential in various spots in the ocean. More than 10 companies have obtained interim leases to begin work along the coasts of Delaware, New Jersey, Georgia, Florida and California. Still, there are no guarantees that those businesses will be able to obtain approval to work the patches of ocean they are researching.

Moving Too Fast?

Ocean-energy projects are also making surfers and fishermen nervous. Those groups say they want to be consulted on any proposed projects because the impact on ocean recreation, ecology, public safety and fishing remains mostly unknown.

“What we want is that any company who wants to put a project in waters used by commercial fishermen contact the local fishermen group and work with them so they don’t harm the fishing industry,” says Linda Buell of the Fisherman’s Advisory Committee of Tillamook, a large coastal county in Oregon. “Nothing right now is written into the rules.”

Marine scientists, meanwhile, want more research done on the unintended consequences that large ocean-energy structures could have on marine organisms. These structures could possibly conflict with migratory pathways of great whales, says George Boehlert, director of the Hatfield Marine Science Center at Oregon State University. “But this is largely unknown,” he says.

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US Air Force Academy, Air Force Link, August 20, 2008

The next source of alternative energy could come from ocean waves, and Air Force Academy professors have been granted funding to dive into this research.

The National Science Foundation has awarded the Academy’s Aeronautics Department $285,619 to support a cyclodial propeller wave energy converter research project to harness the ocean’s power.

The concept of ocean waves turning power-generating turbines is simple — put propellers underwater, then let the motion of incoming and outgoing waves, along with tidal currents turn the propellers and turbines to crank out electricity. But making those turbines efficient, effective and survivable in both shallow and deep water is what has prevented large-scale application in harnessing wave energy.

But the Academy’s Aeronautics Department might be able to solve these problems. Years of research on military aircraft have given Aeronautics researchers the rare and necessary expertise in feedback flow control and fluid dynamics to potentially harness wave energy to meet the nation’s growing power needs.

The Aeronautics Department will partner with Oregon State University to use their wave tunnel for some of the experimental side of this research project. Through both computational and experimental research, the Academy will pursue development of a wave energy converter based on cycloidal propellers, like those used on tug boats. These propellers’ main advantage is the ability to produce thrust in any direction perpendicular to the propeller shaft.

This project investigates the use of cycloidal propellers for energy extraction from unsteady flow fields created by both deep and shallow water waves. Both of the three-dimensional flows are a challenge to energy conversion devices since they provide a flow field that fluctuates in time.

Historically, wave energy converters have some drawbacks, one being the need for some kind of mooring to the ocean floor, which increases the cost of the device, as well as susceptibility to damage from storms. The cycloidal propeller based wave energy converters investigated in this project has the potential to overcome this and other problems of conventional wave energy converters, such as scalability to large power levels and efficiency of energy conversion.

“Wave power has the potential to provide a large portion of the world’s electric energy needs, if it can be tapped in an efficient way,” said Dr. Stefan Siegel, who will oversee this research project.

Cadets will also catch this wave, performing the basic research as part of the Aeronautics 471 class during their senior year.

This project, which is funded through 2011, is part of a broader Air Force effort to address energy related issues and to support renewable alternative energies research.

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MICHAEL BARBARO, The New York Times, August 20, 2008

In a plan that would drastically remake New York City’s skyline and shores, Mayor Michael R. Bloomberg is seeking to put wind turbines on the city’s bridges and skyscrapers and in its waters as part of a wide-ranging push to develop renewable energy.

The plan, while still in its early stages, appears to be the boldest environmental proposal to date from the mayor, who has made energy efficiency a cornerstone of his administration.

Mr. Bloomberg said he would ask private companies and investors to study how windmills can be built across the city, with the aim of weaning it off the nation’s overtaxed power grid, which has produced several crippling blackouts in New York over the last decade.

Mr. Bloomberg did not specify which skyscrapers and bridges would be candidates for windmills, and city officials would need to work with property owners to identify the buildings that would best be able to hold the equipment.

But aides said that for offshore locations, the city was eyeing the generally windy coast off Queens, Brooklyn and Long Island for turbines that could generate 10 percent of the city’s electricity needs within 10 years.

“When it comes to producing clean power, we’re determined to make New York the No. 1 city in the nation,” Mr. Bloomberg said as he outlined his plans in a speech Tuesday night in Las Vegas, where a major conference on alternative energy is under way.

He later evoked the image of the Statue of Liberty’s torch, saying he imagined it one day “powered by an ocean wind farm.”

But the mayor’s proposal for wind power faces several serious obstacles: People are likely to oppose technologies that alter the appearance of their neighborhoods; wind-harnessing technology can be exceedingly expensive; and Mr. Bloomberg has less than 18 months left in office to put a plan into place.

Turning New York City into a major source of wind power would likely take years, if not decades, and could require a thicket of permits from state and federal agencies. Parts of New York’s coastline, for example, are controlled by the federal government, from which private companies must lease access.

Mr. Bloomberg is known for introducing ambitious proposals that later collapse, as did his congestion-pricing plan for Manhattan.

But aides said he was committed to developing alternative energy sources in the city, and wanted to jump-start the discussion now.

“In New York,” he said in his speech, “we don’t think of alternative power as something that we just import from other parts of the nation.”

Asserting the seriousness of his intentions, aides said, Mr. Bloomberg met privately with T. Boone Pickens, the oil baron who is trying to build the world’s largest wind farm in Texas, to discuss possibilities for such technology in New York.

And on Tuesday afternoon the city issued a formal request to companies around the country for proposals to build wind-, solar- and water-based energy sources in New York. “We want their best ideas for creating both small- and large-scale projects serving New Yorkers,” Mr. Bloomberg said.

Rohit Aggarwala, the director of the city’s Office of Long-Term Planning and Sustainability, said that turbines on buildings would likely be much smaller than offshore ones. Several companies are experimenting with models that look like eggbeaters, which the Bloomberg administration says could be integrated into the spires atop the city’s tall buildings. “”You can make them so small that people think they are part of the design,” Mr. Aggarwala said.

“If rooftop wind can make it anywhere, this is a great city,” he said. “We have a lot of tall buildings.”

Creating an offshore wind farm, he said, requires “pretty much the same level of difficulty as drilling an oil rig, but you don’t have to pump oil.”

“You could imagine going as much as 15, 20, 25 miles offshore, where it’s virtually invisible to land,” he said.

Mr. Aggarwala said that developing renewable energy for New York would take considerable time. “Nobody is going to see a wind farm off the coast of Queens in the next year,” he said.

But “the idea of renewable power in and around New York City is very realistic,” he said. “The question is what type makes the most sense and in what time frame. That is what we are trying to figure out.”

The city has experimented with wind power before. It put a turbine on city-owned land at 34th Street and the East River several years ago, but found that the technology was not efficient enough to expand.

The mayor’s plan includes the widespread use of solar panels, possibly on the roofs of public and private buildings. One proposal is to allow companies to rent roofs for solar panels and sell the energy they harvest to residents.

The city is already using tidal turbines under the East River that provide energy to Roosevelt Island. That technology could be widely expanded under the mayor’s proposal.

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CLAIRE BATES, The Daily Mail, July 17, 2008

The first ever commercial electricity powered by the tides has been put on the National Grid, project managers said today.

The £10million SeaGen turbine based in Northern Ireland’s Strangford Lough generated enough green energy to supply 150 homes in a test. Full-blown production is expected in a few weeks’ time.

The SeaGen in Strangford Lough will generate 1.2 megawatts of power at full capacity

Working like an underwater windmill, the turbine’s two rotors are propelled by some of the world’s fastest tidal flows that stream in and out of the Lough at speeds of up to 8 knots.

It is moored to the sea floor 400 metres from the shore and will work for about 20 hours each day. No energy is generated during tide changes as tidal speed drops to below 2 knots.

The SeaGen has two rotors that will revolve 10 to 15 times a minute

Once fully operational Seagen, run by Marine Current Turbines (MCT) Ltd, will generate 1.2 megawatts of hydropower, supplying the equivalent of 1,000 homes.

Managing director Martin Wright said: ‘This is an important milestone for the company and indeed the development of the marine renewable energy sector as a whole.

‘SeaGen, MCT, tidal power and the UK Government’s push for marine renewables all now have real momentum.’

Tidal energy is generated by the relative motion of the Earth, Sun and Moon, which interact via gravitational forces.

Although more expensive to develop it is far more predictable than wind energy or solar power.

Energy Secretary John Hutton said: ‘This kind of world-first technology and innovation is key to helping the UK reduce its dependency on fossil fuels and secure its future energy supplies.

‘Marine power has the potential to play an important role in helping us meet our challenging targets for a massive increase in the amount of energy generated from renewables.’

Strangford is a breeding ground for common seals, but the company said the speed of the rotors is so low – no more than 10 to 15 revolutions per minute – that they are unlikely to pose a threat to marine wildlife.

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Environment-Expert.com, July 23, 2008

EDF shall build the first pilot tidal turbine system in France in order to produce electricity from the energy in tidal currents. By 2011 between three and six turbines, with a total capacity of between 4 and 6 MW, will be installed and linked to the grid off Paimpol (Côtes d’Armor, Brittany), where the currents are amongst the strongest in Europe. This world first is the culmination of more than four years of consultation and preparatory work along the coasts of Brittany and Normandy. The choice of the Paimpol-Bréhat site was based on technical and financial criteria. In addition elected representatives, environmental protection associations and all those involved with the sea are united in strongly approving the welcome given to the project by local decision-makers.

This pilot scheme will enable the technology to be tested under real conditions, thus allowing its profitability to be assessed and an administrative and legal framework that will lead to the development of a network in France to be drawn up.

In fact energy from tidal currents emits no greenhouse gases and has the advantage of being completely predictable. Therefore in the long term this new source of energy could make a significant contribution to the production of electricity from renewable sources, in particular in the United Kingdom and France, France alone having 80% of the potential for generating electricity from tidal currents in Europe, i.e. 10 million MWh per year.

According to Pierre Gadonneix, EDF’s Chairman and Managing Director, “EDF, which thanks to nuclear and hydraulic power is the energy producer that emits the least CO2 in Europe, is making developing renewable types of energy one of its priorities. This tidal turbine project, which is in keeping with this policy, is a response to the work done at the French Environment Forum. In fact the power of the sea is a reliable and inexhaustible source of electricity that can help to respond to people’s increasing energy requirements and to fulfill international commitments to reduce emissions of greenhouse gases.”

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GLOBE-NET NEWS, May 29, 2008

Forever moving – our restless oceans have enough energy to power the world. As long as the Earth turns and the moon keeps its appointed cycle, the oceans will absorb and dissipate vast amounts of kinetic energy – a renewable energy resource of enormous potential. But harnessing this resource has proven more difficult than first thought. In this the latest installment of the GLOBE-Net Series on Renewable Energy – we look at how the power of the oceans might eventually find its place among other forms of renewable energy.

Ocean Energy – What is it?

According to the United Nations, 44% of the world’s population lives within 150 km of an ocean coast. In Canada and Australia the number is much higher at 80%. In the United States 53% of the population lives in close proximity to an ocean.

Thus it is only natural that many countries look to the oceans as a source of energy to be harnessed. How they seek to exploit this resource varies according to factors of geography and available technologies.

The two main forms of energy associated with our oceans are tidal power and wave power – born of the same source, but different in how they turn energy into electricity.

Tidal Power

Tidal power coverts the energy of tides into electricity utilizing the rise and fall of the ocean tides. The stronger the tide, either in water level height or tidal current velocities, the greater the potential for tidal electricity generation.

Tidal generators act in much the same way as do wind turbines, however the higher density of water (832 times that of air) means that a single generator can provide significant power at velocities much lower than those associated`with the wind power generators.

Tidal power can be classified into two main types; Tidal Stream Systems and Barrages.

Barrages are similar to hydro-electric dams but are placed in an estuary bay or river mouth, where they act as barriers that create artificial tidal lagoons. When water levels outside the lagoon changes relative to water levels inside, turbines in the barrages are able to produce electrical power. There are only three such structures in the world: the Rance River in France, Canada’s Bay of Fundy, and Kislaya Guba, Russia.

Tidal stream systems make use of the kinetic energy of moving water to power turbines. This technology simply relies on individual turbines which are placed in the water column; moored to be suspended, floating or anchored to the ocean floor. As the tide flows in or out, electrical energy is produced as water moves through the turbine.

Tidal power boasts several advantages over other types of renewable energy technology, because tides are more predictable and reliable than wind energy or sunny days for solar power. Tidal energy has an efficiency ratio of approximately 80% in terms of converting the potential energy of the water into electricity. Tidal stream system turbines are only a third the diameter of wind rotors of the same power output.

As with wind power, location is important factor in terms of being able to harness the earth’s natural energy. Tidal stream systems must be located in areas with fast currents where natural flows are concentrated between natural obstructions, for example at the entrances to bays and rivers, around rocky points or headlands, or between islands and other land masses.

Wave Power

Ocean surface waves are also a considerable source of energy potential, but energy that is not as restricted in terms of location as tidal energy systems. Typically wave energy is captured using buoys which generate mechanical energy as they oscillate vertically from wave motion.

Terminator devices extend perpendicular to the direction of wave travel and capture or reflect the power of the wave. Water enters through a subsurface opening into a chamber with air trapped above it and wave action causes the captured water column to move up and down like a piston to force the air though an opening connected to a turbine.

A point absorber is a floating structure with components that move relative to each other due to wave action (e.g., a floating buoy inside a fixed cylinder). The relative motion is used to drive electromechanical or hydraulic energy converters.

Attenuators are long multi-segment floating structures oriented parallel to the direction of the waves. The differing heights of waves along the length of the device causes flexing where the segments connect, and this flexing is connected to hydraulic pumps or other converters.

Overtopping devices have reservoirs that are filled by incoming waves to levels above the average surrounding ocean. The water is then released, and gravity causes it to fall back toward the ocean surface. The energy of the falling water is used to turn hydro turbines.

Wave power varies considerably in different parts of the world, and wave energy can’t be harnessed effectively everywhere. According to the Ocean Renewable Energy Group, a Vancouver based organisation that promotes the development of ocean energy in Canada, regions considered to have “good” wave energy resources are generally those found within 40 to 60 degrees of latitude, where the strongest winds are found. Wave-power rich areas of the world include the western coasts of Scotland, northern Canada, southern Africa, Australia, and the northwestern coasts of the United States.

Projects Underway

Ocean energy company Clean Current Power Systems estimates a potential global market for 67,000 Megawatts (MW) of tidal and wave action equipment worth $200 billion. At 20 cents/kW hour, the market for tidal electricity could be $27 billion annually. According to Finavera, world-wide wave energy could provide up to 2,000 TWh/year, 10% of world electricity consumption.

It comes as no surprise then, that interest in ocean energy has been building momentum in the past few years as these nations scramble to meet renewable energy targets.

For instance, in November 2007, British company Lunar Energy announced that it would be building the world’s first deep-sea tidal-energy farm off the coast of Pembrokshire in Wales. Eight underwater turbines, each 25 metres long and 15 metres high will provide electricity for 5,000 homes. Construction is due to start in the summer of 2008 and the proposed tidal energy turbines, described as “a wind farm under the sea”, should be operational by 2010.

Plans for a ten-mile barrage across the River Severn, which could generate 5% of the UK’s electricity needs, are currently under development. According to the UK Sustainable Development Commission, a barrage across the Severn would produce clean and sustainable electricity for 120 years. This would have a capacity of 8,640MW and an estimated output of 17 terawatt hours a year.

Scotland boasts roughly 25% of the entire European Union’s tidal power potential and 10% of its wave energy potential and could produce more than 1,300 megawatts by 2020, enough to power a city the size of Seattle. In 2007, Scotland announced $26 million worth of funding packages to develop marine power in the nation. So far $8 million has been procured to develop 3 MW of tidal power.

UK based Marine Current Turbines is developing a tidal stream system off the coast of Ireland. The 1.2-megawatt turbine will be tested for 12 weeks before feeding power into the Northern Ireland grid where it will operate for up to 20 hours per day, producing enough electricity to power 1,000 homes.

Both Scotland and England are planning wave energy projects. Scotland will be developing a 3MW array and England will be developing a 20 MW Wave Hub off the north coast of Cornwall, England. The Cornwall project will power up to 7,500 homes.

Canada has the world’s longest coastline and has always been serious about harnessing ocean energy. In early 2008 the Government of Nova Scotia gave the green light to three tidal energy testing projects in the Bay of Fundy to help establish a permanent tidal energy farm (see GLOBE-Net Article Nova Scotia to fund tidal power research). Irving Oil is also studying 11 potential sites in the Bay of Fundy to develop tidal energy farms.

The Government of British Columbia estimates there are more than 6,000 megawatts of potential wave energy that have been identified so far in the province and projects are already underway to develop wave energy systems. In 2006 Vancouver based Clean Current Power Systems began developing a pilot tidal power project near Victoria to demonstrate the potential for tidal power.

PG&E and Vancouver-based Finavera Renewables is developing America’s first commercial wave power plant off the coast of Northern California. The plant is scheduled to begin operating in 2012, generating a maximum of 2 megawatts of electricity.

In March, 2008, the U.S. Department of Energy announced would be offering up to $7.5 million in grants for hydro-kinetic energy such as wave and tidal power. The department is seeking partnerships with companies and universities to develop the technologies and plans to award up to 17 grants.

Portugal is planning the world’s first commercial wave farm, the Aguçadora Wave Park near Póvoa de Varzim. If successful, a further 70 million euro is likely to be invested before 2009 on a further 28 machines to generate 72.5 MW.

The Challenges

Despite the enormous potential of ocean energy, there remain many pitfalls (if such a word can be used in a watery context) that have proven difficult to overcome, and which explains why ocean energy remains the least developed of all forms renewable energy. Problems still exist regarding cost, maintenance, environmental concerns and our still imperfect understanding of how power from the oceans will impact on the world’s energy infrastructure.

For example, turbines are susceptible to bio-fouling; the growth of aquatic life on or in the turbine. This can severely inhibit the efficiency of energy production and is both costly and difficult to remove. Turbines are also prone to damage from ocean debris.

In the Bay of Fundy, project developers are particularly concerned with ice floes the size of small apartments, and cobblestones the size of watermelons constantly being tossed across the Bay’s terrain by the power of the Bay’s water flows.

Turbines may also be hazardous to marine life and the impacts on marine life are still largely unknown, but concern is warranted.

Barrage systems are affected by problems of high initial infrastructure costs associated with construction and the resulting environmental problems. For example, independent research on the economics of building the proposed Severn Barrage in the UK revealed that, taking environmental costs into account, the structure could cost as much as $12 billion to create – $4 billion more than previously estimated.

Barrage impacts include a decrease in the average salinity and turbidity within a barrage, significantly altering associated ecosystems.

Wave power systems present their own set of challenges. Most electric generators operate at higher speeds, and most turbines require a constant, steady flow. Unfortunately wave energy is slow and ocean waves oscillate at varying frequencies.

The rough realities of the marine environment have also proven difficult to deal with, especially for companies seeking to remain cost-effective. Constructing wave devices that can survive storm damage and saltwater corrosion add to development costs.

The Future

Modern advances in ocean energy technology may eventually see large amounts of power generated from the ocean, especially tidal currents using the tidal stream designs. The technology is still in its infant stage and most projects that exist or are that are in project development stages are mainly pilot projects. But the promise remains.

“It’s not as well-established as solar, thermal, wind and biomass, but it [ocean power] shows a lot of promise,” said Philip Jennings, professor of energy studies at Western Australia’s Murdoch University.

“As the technology develops and becomes more affordable, which it will over time, we can continue to expand pretty much anywhere where there is an ocean,” said Chief Executive Officer Phil Metcalf of Pelamis Wave Power.

The market potential for tidal power still remains unclear [says who?]. Sector analysts believe Initial Public Offerings (IPO) for wave and tidal power projects will be much harder to price than for comparable wind power projects, because wave firms cannot give exact estimates on the scale of benefits and few have technologies that are up and running.

Regardless, both ocean wave and tidal power have attracted growing interest from investors and power utilities looking for the next long-term play in renewable energy.

“Water covers more than 70 percent of the Earth’s surface,” said Andy Karsner, assistant secretary for energy efficiency and renewable energy at the DOE. “Using environmentally responsible technologies, we have a tremendous opportunity to harness energy produced from ocean waves, tides or ocean currents, free-flowing water in rivers and other water resources to…provide clean and reliable power.”

According to Jennings ocean power could not match fossil fuels for electricity production but could be competitive with other forms of renewable energy.

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Net News Publishers, May 6, 2008

Work to determine the potential of a tidal energy generator in the Severn Estuary is continuing with the appointment of a consortium led by consulting firm Parsons Brinckerhoff who will manage the Strategic Environmental Assessment (SEA).

The SEA is a major part of the Severn Tidal Power Feasibility Study. It will provide analysis of how the environment around the estuary will be affected if a tidal range power project goes ahead.

The Secretary of State for Energy, John Hutton, announced the start of the two year long feasibility study in January. The tidal energy resource in the Severn Estuary provides the largest potential of all the UK’s estuaries for renewable electricity generation. John Hutton said: “A Severn tidal power project could be larger in size, output and cost than any other energy project in this country. It has the potential to generate up to 5% of the UK’s electricity demand and contribute significantly to the proposed EU renewable energy targets. It’s therefore vitally important we undertake the most thorough and exhaustive study and contract the right companies to take this work forward”.

Minister for the Environment at the Welsh Assembly Government, Jane Davidson said: “The Welsh Assembly Government is committed to increasing the amount of energy generated from renewable sources so as to help address the serious issue of climate change. We must, therefore, consider carefully the opportunity to harness tidal power in the Severn Estuary. I am very much aware of the estuary’s environmental importance and the environmental protection legislation that, quite rightly, will need to be taken fully into account. There is a great deal at stake and our assessments during the feasibility study must be rigorous and based on sound science.”

PricewaterhouseCoopers has been appointed to advise the Department for Business, Enterprise and Regulatory Reform (BERR) on how such a project could be financed and ownership options. Consideration will be given to the full range of possibilities, including the need for any government support

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Renewable Energy Development Blog, April 23, 2008

DeltaStream by Eco2The latest Tidal Energy venture is a demonstration project in Welsh waters backed by renewable energy developer Eco2, investing £150,000 into Tidal Energy Limited as the company installs DeltaStream. The finance needed by Tidal Energy Limited, which was formerly known as Tidal Hydraulic Generators, will fund the prototype phase of this 12 month operation, reaching £6 million. Eco2 will fund £1 million which has been matched by the Carbon Connections Development Fund.

DeltaStream is tidal stream technology, distinct from other devices as it does not require fixing to the sea bed. Each DeltaStream energy device is a 1.2MW capacity generator made up of three turbines in a triangular frame. The frame itself is comparatvely light which will positioning with a minimum of effort. To prevent the DeltaStream from being shifted by the currents it will require some form of ballasting.

The DeltaStream is modular as the components can be exchanged for maintenance or repair. This makes the DeltaStream energy device considerably cheaper to maintain than comparable tidal systems.

Tidal Energy Limited plans to begin manufacturing the device later in 2008 with a view to beginning full-scale installation in 2009.

David Williams, Chief Executive of Eco2, said: “This is an important development as it literally takes renewable power generation out of sight, minimising environmental impact, yet harnessing the largely untapped energy resources of the oceans, far more cost effectively than before. We believe this is the most aesthetic and energy efficient solution yet to meeting EU renewable energy targets.”

More information can be found by reading the Carbon Connection DeltaStream Case Study.

Some more Tidal Energy turbines in development around the world

SeaGen at Strangford Lough, Northern Ireland
Tocardo Turbines at Pentland Firth, Scotland
Rotech Tidal Turbines at Wando Hoenggan Waterway, South Korea
Free Flow Turbines at St Lawrence River, Canada

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http://www.inthenews.uk.co, April 7, 2008

Planning permission has been granted by the Energy Secretary for a tidal stream generator to be tested in the Humber estuary, Stallingborough, United Kingdom.

When in the water the prototype model is estimated to generate up to 0.15MW and it will be one of the first tidal power machines to supply Great Britain’s national grid.

The generator will be positioned off the south bank of the Humber at Upper Burcom near Stallingborough.

It will work by extracting energy from underwater currents in a similar way to wind turbines.

Energy from tidal flows will power a pair of straight horizontal hydrofoils, 11m in length, which will move up and down like a dolphin’s tail.

If it is successful then it will be used to develop larger 1MW units which could be used in arrays generating up to 100MW each. This is enough to power the equivalent of 70,000 homes.

The project, developed by Pulse Tidal Ltd., has been given backing of £878,000 from the government.

“Our continued support for these emerging technologies is essential if the UK is to cement its position as a world leader in marine technologies,” said Energy Secretary John Hutton.
“I have made clear our commitments to renewable energy and to marine technologies. We will be doubling the support available for those technologies under the Renewables Obligation.

“This kind of tidal project, if proven, will go some way to helping the UK meet its ambitious targets for clean, green energy.”

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ANTHONY DOESBURG, New Zealand Herald, April 28, 2008

An experimental turbine generating 1MW will be installed in Cook Strait off Island Bay Summer 2008, costing $10 million.

A prototype of what is likely to be the first turbine for tapping the tidal energy of New Zealand waters is sailing around Scottish seas bolted to a ship.

Christchurch company Neptune Power wants to begin installing an experimental turbine in Cook Strait next summer, based on the design being tested off Scotland.

Neptune received resource consent from the Greater Wellington Regional Council this month for a trial that can last up to 10 years.

Neptune director Chris Bathurst said the company was awaiting the results of the shipboard testing before buying a turbine from the unnamed manufacturer.

So far it has been established that the turbine rotates as intended and now performance and reliability testing is under way.

“Because they wanted to measure how much power it develops at exact speeds, they’ve bolted it to the front of this vessel, which is much easier than measuring where you’ve got variable tidal flows,” Bathurst said.

The turbine Neptune intends installing at a cost of $10 million 4.5km off Wellington’s Island Bay will have a maximum generation capacity of 1MW – enough for about 500 homes.

That is a fraction of the 12GW of power – 1.5 times New Zealand’s present generation capacity – Bathurst calculates could be extracted from Cook Strait at a cost of billions.

Bathurst, a mechanical engineer with a background in the aluminium smelting industry, is not daunted by that sum. He says he is well versed in capital raising, having been involved from the beginning in a successful US$1.3 billion smelter project in Mozambique.

“I’m quite sure we could bring in overseas money for this because people will see it as a way of attracting carbon credits.”

But he wants New Zealand investors to have priority, and would like up to a third of the venture’s value to be available to the public.

“We’ve turned various offers of investment down because first we wanted to get resource consent and know that the technology is going to work. Then we would go after the money, and we’re at that stage now.”

It is intended that the turbines will be made in New Zealand. The 14m-diameter machines are made of carbon fibre so yacht builders are potential manufacturing partners.

The turbine’s carbon fibre construction should give it three times the generation capacity per tonne of a conventional wind turbine, Bathurst said.

“It’s very light. That means when we get into mass production it will be correspondingly cheaper as well. Manufacturing costs generally are in line with the mass of the materials used.”

Bathurst can see New Zealand becoming an exporter of marine energy expertise in the same way that it is a world leader in geothermal power generation.

The turbine itself might be light but it will be held in place by a concrete tank weighted with 700 tonnes of a material that is yet to be finalised.

The trial turbine will be anchored with a heavier weight than is likely to be needed for the production turbines because it is not known what forces they will have to withstand.

“After we’ve had it down for a period and analysed the forces, we’ll be able to be more accurate about the weight needed.”

The turbine will be placed in waters known as the “Karori rip”, an area where the tidal current changes orientation from east-west to north-south where Wellington juts into Cook Strait.

“That speeds up the current at that point – a bit like a bend in a river,” Bathurst said.

Power from the trial turbine is expected to be brought ashore at Vector’s Island Bay substation.

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Nova Scotia Premier’s Office, January 8, 2008

Nova Scotia is one step closer to building North America’s first in-stream tidal technology centre to host some of the world’s leading devices to harness energy from the world’s highest tides.

Three candidates, representing technologies from Canada, U.S.A. and Ireland, have cleared the first hurdle in their bid to demonstrate tidal devices in the Bay of Fundy and the province has given Minas Basin Pulp and Power conditional approval to build the host facility.

“These companies know what we know — the Bay of Fundy is one of the world’s best sites for tidal development,” said Premier Rodney MacDonald. “And today we are a step closer to proving it. This facility can become a landmark centre of excellence in our efforts to provide cleaner sources of energy.

“The more we move away from coal-based electricity, the more we protect our environment — a key priority for this government.”

The facility will be funded by a $4.7-million grant from the province’s Ecotrust for Clean Air and Climate Change program, a $3-million zero-interest loan from EnCana Corporation’s Environmental Innovation Fund, and significant contributions from each of the successful developers. The province will also make $300,000 available for environmental and permitting work.

“We are grateful for the shared desire today to help create a brand new industry,” said Energy Minister Richard Hurlburt. “And we are pleased to welcome some of the world’s most promising technology to our province. If we combine that technology with Nova Scotia’s offshore expertise, research capacity and enormous tidal resource, this can become a truly outstanding centre of excellence.”

Gerry Protti, president of EnCana Corporation’s offshore and international division added,”EnCana is pleased to support the development of a promising and untapped energy resource here in Nova Scotia. Unlocking the unconventional power of the tides requires innovative thinking and the kind of creative partnerships that will be generated at this centre.”

The three candidates in negotiations for first occupancy in the proposed facility are:

      

  • Clean Current (using a Clean Current Mark III Turbine)
  • Minas Basin Pulp and Power Co. Ltd. (UEK Hydrokinetic Turbine)
  • Nova Scotia Power Inc. (OpenHydro Turbine)
  •  

     

Minas Basin Pulp and Power Company proposes to construct the facility infrastructure, which would connect all tidal devices from the Bay of Fundy to the Nova Scotia electric grid.

“As a Nova Scotia company, we’re extremely pleased to play a role in moving tidal technology forward,” said John Woods, vice-president of energy at Minas Basin Pulp and Power. “The fact that we’ll be working together with devices from both North America and Europe shows the potential global reach of this technology.”

Glen Darou, Clean Current’s president and CEO added, “Nova Scotia is demonstrating strong leadership in sponsoring this world-class demonstration site. The Clean Current team is delighted to be part of this history-making event. The Clean Current Mark III turbine that we will install here is simple, efficient and environmentally friendly.”

Ralph Tedesco, president and CEO of Nova Scotia Power said
“Nova Scotia Power and OpenHydro are proud to be helping harness this silent, invisible, predictable energy — renewable liquid gold from the Bay of Fundy.”

“Tidal energy has the potential to help Nova Scotia meet its 2020 deadline to cut greenhouse gas to 10% below 1990 levels,” said Mr. Hurlburt. “But please remember — a number of conditions must be met before anything goes in the water.”

These conditions include the completion of:

      

  • A strategic environmental assessment (expected spring 2008 )
  • Site-specific environmental assessment(s)
  • Provincial and federal permits and approvals
  • A contribution agreement between province and developer(s)
  • A land lease agreement between province and developer(s)
  •  

     

Research identifies the Bay of Fundy as potentially the best site for tidal power generation in North America, with a world-class resource in close proximity to an existing grid and potential consumers.

Nova Scotia’s regulations demand nearly 20% of the province’s electricity supply come from renewable sources by 2013. In-stream tidal energy has the potential to help meet that target.

Tidal technology also holds potential future opportunities for Nova Scotia suppliers and manufacturers, many of whom already have experience in Nova Scotia’s offshore petroleum industry.

The Nova Scotia departments of Energy, Environment and Labour, and Natural Resources have worked together to develop the project, in support of one of the province’s five priorities — protecting the environment.

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RenewableEnergyDev.com, April 8, 2008

A Dutch tidal device developer has recognised the potential in the Scottish waters and is planning a new tidal energy power plant in the Pentland Firth, hoping to begin development as early as the end of 2008.

Tocardo has established a subsidiary company called Tocardo Tidal Energy with the plan to set up production, assembly and office facilities in Wick Harbour. The major goal is to construct a 10MW offshore tidal energy plant which has tentatively been christened the Pentland Firth Tidal Energy Park. This first foray harnessing tidal energy in the Pentland Firth is expected to be a mere drop in the ocean, as it were, for future tidal power projects in the region.

The project plans to use the Tocardo technology which is a twin-bladed horizontal axis turbine with direct drive generator and fixed pitch blades. The rotor blades on the turbines will be 10m in diameter and will be capable of generating 650kW each.

A pre-feasibility study has been prepared by Tocardo BV Tidal Energy to identify the tasks required for a Tidal Master Plan Study. The Tidal Master Plan Study will be the feasibility study to determine the best way forward towards accelerated development of the tidal energy potential of the Pentland Firth.

An objective has been set in place by the Scottish Government to harness 1300MW of tidal energy in the Pentland Firth by 2020.

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Ocean Energy Council, April 23, 2008

A renewables company based in Cardiff is looking to make commercial waves from a marine energy venture.

Eco2 is the major shareholder and commercial driver of Tidal Energy which has developed an innovative technology to generate electrical power from tidal stream resources.

Its DeltaStream technology takes the concept of wind turbine and ship propeller systems deep beneath the ocean, each generating 1.2 megawatt of energy.

DeltaStream generator features three turbines which sit on the seabed in a triangular frame. When deployed, they will be situated in formation across the seabed to generate green electricity.

Eco2 is spearheading a £6m fundraising exercise, £1m of which it will provide itself. It has already invested £150,000, which has been matched by the Carbon Connections Development Fund, which facilitate knowledge transfer between universities and research laboratories and the business community to speed commercial development of carbon-saving projects,

Chris Williams, project director at Tidal Energy said: “We are hoping to grow this business in Wales, and are looking at a number of suitable locations both in Wales and throughout the rest of the UK for the devices to be installed.

“The skills and resources to develop this business are readily available in South Wales, and we are looking to become a significant employer in this industry with up to 100 full time staff, both in management and operational positions by 2015.”

Following full-scale underwater trials at Cleddau in Pembrokeshire of an early prototype, Tidal Energy is planning to begin manufacturing its device later this year, with a view to full-scale installation in summer 2009.

During the initial stages of the technologies development, Cardiff University contributed to the design of the system’s fluid dynamics and further refinement of the turbine’s blade design is being carried out by Cranfield University in England.

David Williams, chief executive of Eco2, said: “This is an important development as it literally takes renewable power generation out of sight, minimising environmental impact, yet harnessing the largely untapped energy resources of the oceans, far more cost effectively than before. We believe this is the most aesthetic and energy efficient solution yet to meeting EU renewable energy targets.”

The British Wind Energy Association estimates marine power could provide 10-20% of the UK’s electricity needs.

Established in 2002, Eco2 specialises in initiating, developing, financing and operating renewable energy projects and is currently working on wind, biomass and tidal stream projects across the UK.

Eco2 is committed to significantly contributing to Wales reaching the targets set out by the Welsh Assembly Government to generate 4 terawatt (one billion kilowatts) hours of electricity from renewable sources by 2010.

Within Wales, Eco2 has 100 megawatt of wind energy generators either built or in the planning system and a further 160 of biomass projects in development.

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RenewableEnergyDev.com, March 17, 2008

rotech-tidal-turbineAn agreement has been signed to develop a huge tidal power field off the South Korean coast. The joint venture between Lunar Energy of the U.K. and Korean Midland Power Company will develop the tidal power plant in the Wando Hoenggan waterway at a construction cost of £500 million.

The scheme will use power from fast-moving tidal streams to turn a field of 300 60-foot high tidal 1MW turbines sitting on the sea floor. This gives the proposed scheme an operating capacity of 300MW. According to the press release, the power produced from the tidal power plant will generate enough electricity for 200,000 homes and will be completed by the end of 2015. 

The manufacture and installation of the tidal turbines will be carried out by Hyundai Heavy Industries while Aberdeen-based research and development company Rotech Engineering will provide the specialist components.

According to a Lunar Energy spokesman “It is intended that full resource research and feasibility be completed by July 2009 with the installation of a 1MW pilot plant by March 2009.

“Each one megawatt unit has a turbine diameter of 11.5m and a fully ballasted weight in excess of 2500 tons. Rotech tidal turbines can be easily grouped to suit tidal streams in locations worldwide.”

This is the kind of project that could make the U.K.’s proposed £15 billion Severn Barrage project, which has been facing mountains of environmentally based opposition, obsolete. It will also open up an enormous potential for future developments in the oceans worldwide. If proven, we could be witnessing the pioneering of the energy system of the future for coastal cities with potential energy levels in the tens of thousands.

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LARRY GREENEMEIER, Scientific American, March 10, 2008

Thirty feet (nine meters) below Manhattan’s East River, next to Roosevelt Island, six turbines—each 16 feet (five meters) in diameter, churning at a peak rate of 32 revolutions per minute—stand at attention on the riverbed. The turbines—which belong to New York City-based Verdant Power, Inc., —are built on a swiveling platform that keeps their nose cones facing the tide, whether it’s coming in or going out. Resembling an underwater wind farm, these kinetic hydropower systems use gearboxes and speed increasers—which convert the slower rotating rotor into a faster rotating generator—to transform each turbine’s mechanical power into electricity.

Verdant’s turbines require tides that move at least six feet per second in order to generate enough energy for them to be cost-effective, and the East River is more than obliging. “The East River is a good tidal channel that links the Long Island Sound to the ocean,” says Trey Taylor, the company’s president and head of market development. “Plus, New York is an expensive place to buy power, so it would be easier here to prove that this could help.”

A few dozen feet away from the closest turbine, an onshore control room gets a feed of the energy created by the entire cluster. To prove that this energy could be usable for local businesses, Verdant last year sent a test transmission of electricity to a supermarket and parking garage on Roosevelt Island that were willing to participate in the Roosevelt Island Tidal Energy project.

The Earth’s oceans, pushed by wind and tugged by the moon and sun, ebb and flow over more than 70 percent of the planet, but only recently has technology emerged to finally harness some of that kinetic energy as usable power for us landlubbers. Underwater turbines, submerged “wind” farms and wave-riding electrical generators are being tested around the world, with new advances in technology promising relief for overworked energy utilities. “We consider wave energy to be more predictable than wind,” says Phil Metcalf, CEO of Edinburgh-based Pelamis Wave Power, Ltd., a company taking a different approach than Verdant in developing ocean power–utilizing devices. “You look at the ocean 1,000 miles out, you’ll get a good idea of what to expect over the next 24 to 48 hours. We think it’s actually going to be easier to dispatch to the grid.”

Pelamis’s devices are big red tubes, each 426.5 feet (130 meters) long, 13 feet (about four meters) in diameter, weighing around 750 tons (635 metric tons), and with a life expectancy of up to 20 years. They flex as the ocean swells around them. The wave-induced motion of the tubes’ joints is resisted by hydraulic rams, which pump high-pressure fluid through hydraulic motors that drive electrical generators to produce electricity. Power from all the joints is fed down a single umbilical cable to a junction on the seabed. Three of the tubes, which work best at a depth of 165 to 230 feet (50 to 70 meters) and roughly 3.7 miles (six kilometers) from the shore, can produce up to 2.25 megawatts.

Pelamis—which until September had been called Ocean Power Delivery—has taken its prototype through about 2,000 hours of testing at the European Marine Energy Center’s wave test site near Scotland’s Orkney Islands. Three additional machines will form the initial phase of Agucadoura, the world’s first commercial wave farm, in April off the coast of Portugal, a project developed by Portuguese utility Enersis, a subsidiary of Babcock and Brown. Pelamis is negotiating with other utilities and governments as well, with future deployments depending on how well the Portuguese project is able to turn waves of water into currents of electricity.

The waters around Scotland are also host to tidal turbine testing by several organizations, including Lunar Energy, Ltd., in East Yorkshire, England, which in March 2007 announced a deal with Germany-based power utility E.On UK, to develop a tidal stream power project of up to eight megawatts off Scotland’s west coast.

Meanwhile, Florida researchers may soon be testing both wave- and tide-powered energy technologies that could take advantage of the Gulf Stream, which flows north-northeastward about 15 miles (25 kilometers) off Florida’s southern and eastern shores at more than eight billion gallons (30 billion liters) per second. Researchers at Florida Atlantic University’s Center of Excellence in Ocean Energy Technology in Dania Beach, Fla., are using a $5-million state research grant awarded in late 2006 to develop air-conditioning technologies that tap into the powerful Gulf Stream and large water temperature differences off Florida’s shores. The researchers envision thousands of underwater turbines producing as much energy as 10 nuclear power plants and supplying one third of the state’s electricity. The university is working with academic, government and industry partners on the project, including the University of Central Florida in Orlando, the U.S. departments of Navy and Energy, Lockheed Martin, Oceaneering International, Inc., in Hanover, Md., and Verdant Power, which has provided them with a 10-foot (three-meter) diameter rotor system that they used during 2002 East River tests.

Verdant first began testing its three-blade, horizontal-axis turbines from the surface of the East River in 2002. There have been some hitches: Some of the turbines’ fiberglass blades broke under the tidal force. (The fiberglass blades will be replaced by the end of April with ones made of a magnesium alloy.)

Still, the site has produced nearly 50,000 kilowatt-hours of energy from December 2006 to May 2007. Verdant’s East River testing spot has the potential to support as many as 300 turbines and nearly 10 megawatts of installed capacity. Verdant has been working for the past several years to tweak its tidal turbines so that by the end of 2010 they can deliver up to 1.5 megawatts to the city’s electrical grid (800 households use about one megawatt).

The East River is not Verdant’s only site. The company is also testing its technology in Canada’s St. Lawrence River near Cornwall, Ontario, with the hope of creating a turbine infrastructure capable of producing an output of 15 megawatts. The company is also looking at sites in China and India.

It is unclear just how much it will cost to tap into energy from large bodies of water, since there is no tidal or wave power industry. Verdant’s Taylor says his company is at least two years away from being able to quote costs to potential customers. That said, a rough cost estimate for Verdant’s marine renewable energy technology is up to $3,600 per kilowatt hour—a higher price tag than wind power, fossil fuels or hydroelectric dams today, he says. However, he also points out that Verdant will be able to lower its costs over time through the mass production of its technology and the reduction of inefficiencies in the licensing and implementation processes.

The next step for Verdant in the U.S. is to apply for a Federal Energy Regulatory Commission (FERC) license that would allow the company to continue its pilot project attempting to prove tidal turbines can be a reliable source of energy for the city’s grid. It took four years to secure the necessary permits from the New York State Department of Environmental Conservation and the U.S. Army Corps of Engineers.

That bureaucratic delay speaks to the difficulty of navigating the regulatory processes required to get such turbines into the water. Verdant’s Taylor says his company has spent about $9 million getting its East River project to its current state, with one third of that cost going toward studies gauging how the turbines might affect vessel navigation, aquatic life and fish migration. Although the New York State Energy Research and Development Authority (NYSERDA) chipped in $3 million toward the East River project, Taylor says the time and money spent to secure changing, and sometimes redundant, regulatory approval wastes precious time that could be used testing new technologies. “That’s got to change,” he adds. “The world is burning up, and we’re fiddling.”

For its part, FERC doesn’t see itself as fiddling as much as trying to find the right tune when it comes new hydroelectric technologies. Chairman Joseph Kelliher last year noted, “these technologies present some challenges relating to reliability, environmental and safety implications, and commercial viability.”

More projects:

In August 2007 nonprofit research and development firm SRI International and Japanese wave-powered generator maker Hyper Drive Corporation, Ltd., tested a prototype ocean wave–powered generator mounted on a buoy in Florida’s Tampa Bay. As the unit bobbed up and down, absorbing energy from the waves, an accordionlike device made of artificial muscle expanded and contracted, creating mechanical energy that was converted into electricity. In the fall SRI will test its more powerful and durable next-generation prototype wave-powered generator.

Finavera Renewables, a Vancouver, British Columbia, renewable-energy technology company, recently signed a contract to deliver power for San Francisco–based Pacific Gas & Electric (PG&E) by 2012. The deal is North America’s first commercial power purchase agreement for a two-megawatt wave-energy project. The PG&E project will be built about 2.5 miles (four kilometers) off the coast of Humboldt County, Calif., for electricity delivery to PG&E’s customers throughout the company’s northern and central California service territory. Finavera’s technology is the AquaBuOY, a floating structure that converts the up-and-down motion of waves into electricity.

The company was also granted a five-year operating license for its one-megawatt Makah Bay Offshore Wave Pilot Project in Washington State by the U.S. Federal Energy Regulatory Commissionthe first-ever FERC license issued for a wave, tidal or current energy project in the U.S. Finavera is also looking to develop wave-power projects off the coast of Oregon and South Africa, and is determining the feasibility of a five-megawatt wave energy project off the coast of Ucluelet, British Columbia.

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JORGE CHAPA, inhabitat.com, December 10, 2007

turbines540One the greatest untapped energy resources in the world is the motion of the ocean. And while floating wind turbines and wave energy generators are being explored throughout the world, there still remains one largely untapped power source, the underwater ocean currents. Well researchers at the Center of Excellence in Ocean Energy Technology have developed what they believe is a technology to allow them to use the Gulf Stream currents that could conceivably cover all of Florida’s energy needs.

The idea is to have underwater turbines placed right in the middle of the Gulf Stream current. The turbines are designed to be about 100 feet in diameter. These will be connected to a buoy that holds the electricity generating equipment. The gulf stream carries billions of gallons per minute, so the impact of these turbines would be minimal if negligible to the current itself.

Now granted, installing all these turbines will take time and significant research, which is why the team is hard at work developing a considerably smaller prototype version that they hope will provide them with enough data to assess whether installing such a system will have an impact in the ocean current, and, just as importantly, all the sealife moving through the area. The prototype will launch in February 2008.

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DAVID ADAMS, tampabay.com, February 4, 2008

It’s free, has zero emissions and sits off the Florida coast just waiting to be tapped.

A boon to ship captains for centuries, could the Gulf Stream, which runs along Florida’s east coast before curving out across the Atlantic, also be a major source of clean energy for the state?

“This is the closest location on the planet of a major ocean current to a significant urban center of electrical demand,” said Rick Driscoll, director of Florida Atlantic University’s Center of Excellence Ocean Energy Technology in Dania Beach, known as Sea Tech. “Its potential is immeasurable.”

Driscoll envisages a vast field of thousands of underwater propeller turbines tethered to the ocean floor – imagine a wind farm hundreds of feet under the sea – slowly spinning in the current.

Some scientists say the Gulf Stream’s vast energy content could provide up to one-third of the state’s electricity needs, equivalent to six nuclear power stations. Realistically, that potential remains something of a dream right now. Of all the emerging alternative technologies, ocean energy is perhaps the least advanced. But it may be starting to catch on.

“Ocean energy is where wind was 20 years ago,” Driscoll said. “There are a lot of concepts and designs.”
Scientists have been studying the power of the Gulf Stream for centuries, but entrepreneurs have only recently begun to take an interest. Projects are just beginning to pop up around the country, in San Francisco Bay, New York’s Hudson River and now Florida’s east coast, though none are in commercial operation yet.

Sea Tech’s ocean energy research is suddenly attracting intense interest. It got a major boost in 2006 with a $5-million grant from the state. It has also formed an alliance with Florida Power & Light Co. Last week Gov. Charlie Crist proposed a $10-million grant in his new budget, and he made his second visit to Sea Tech on Thursday to show his commitment.

“This is a resource that is boundless. I want to do everything I can to help,” Crist said. “It’s a national security issue. The more we can diversify our energy resources, the more independent it will make us.”

Among those intrigued by the concept is influential Tampa Bay area developer and former Ambassador Mel Sembler. Sembler first heard about the potential of the Gulf Stream several years ago when he was approached by an ocean energy pioneer, Jim Dehlsen, who patented one of the earliest turbine designs in 2001.

“I think it’s a fabulous idea,” Sembler said. “It’s so consistent and always in the same general area. To me it is Florida’s answer for alternative energy. We desperately need it.”

Sea Tech began work on ocean energy at its Dania Beach campus in 1999 under the leadership of Driscoll, 37, who holds a dual doctorate in mechanical engineering and oceanography.

Driscoll said the center’s first prototype of an ocean current turbine, 10 feet in diameter, will be deployed later this year. Researchers want to see how the turbines behave in the current and what effect the massive blades might have on migratory fish species.

Early evidence suggests fish just swim around the blades, which rotate at speeds of up to 60 revolutions a minute.
“We see ourselves as the facilitator and a database to help provide the expertise that is needed,” Driscoll said.
Driscoll’s team is creating a profile of the Gulf Stream by placing acoustic Doppler equipment on the ocean bottom. It measures movement by firing sound pulses that reflect off particulate matter in the water.

At its closest, the Gulf Stream is 15 miles offshore and stretches 20 to 30 miles into the Atlantic. It varies from 320 to 650 feet deep, maintaining an average speed of about 5 mph. Crucial to any attempt to harness its energy, the current is confined to an identifiable area. “It doesn’t meander very much,” Driscoll said.

While wind farms have attracted opposition from bird lovers, the notion of undersea turbines has so far not caused a stir. That may be because the Gulf Stream is not especially hospitable to marine life, Driscoll said. Its warmer temperature causes evaporation, making the water saltier.

“I have not heard any concerns,” said Mark Ferrulo, director of Environment Florida, one of the state’s leading nature protection advocacy groups. “If anything, there’s a lot of excitement around this emerging technology.”

Because 70 percent of Florida’s population lives within 10 miles of the ocean, advocates say ocean energy is ideal. Its proximity offshore means reduced transmission costs.

Utilities like the concept as it offers the potential of a steady, reliable supply, unlike solar and wind energy, which are unpredictable due to variable weather conditions.

The potential energy “capture area” stretches about 100 to 200 miles from the lower Florida Keys to St. Lucie County, with the best potential around Miami-Dade, Broward and Palm Beach counties. “This is the sweet spot down here,” Driscoll said.

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BRIAN VANITY, insurgent49, September 1, 2006

As any mariner knows, the oceans are packed full of energy. The energy contained in the seas can destroy ships but, if harnessed correctly, can also be used to generate electricity.

There are several types of energy, which can be extracted from the Alaska’s ocean waters, the two most promising being tidal, and wave energy. Tidal energy is derived from the cyclic rise and fall of the ocean’s tides, while wave energy is harnessed from rapid rise and fall motion of the ocean waves, which are mostly created by the wind. Ocean current energy is extracted from deep-level currents, which are caused by the thermal circulation of the earth’s weather system.

Tidal, wave, and ocean current energy are directly related to conventional hydroelectric power, in that they are all variations of the mechanical energy of moving water. Offshore wind energy is also considered ocean energy, and several offshore wind farms have been built in Europe’s North Sea. In Alaska today, the only wind energy proposals in the state involve on-shore projects.

Tidal Energy

Tidal power uses the energy of the moving ocean tides, which are driven by the gravitational pull of the moon and, to a lesser extent, the sun. The power output is variable, but predictable years in advance.

The natural ebb and flow of the tides potentially offers a huge future energy source for Alaska. In contrast to other variable renewable energy sources such as wind power, the tides are predictable.

Although tidal energy was first used in European grain mills hundreds of years ago, only a handful of tidal power plants exist in the world today, so operational experience is limited. These existing tidal plants are barrage-style, which involve the capital-intensive construction of large tidal dams across an estuary or inlet. Such large structures that block tidal flows usually have significant environmental impacts, similar to those of large dams on rivers.

The largest existing tidal power plant, a 240-megawatt MW facility on the La Rance estuary in northern France, has caused negative environmental effects since being completed in 1966. The only other large-scale tidal power plant in operation today is the 20 MW Annapolis Royal facility, located along the Bay of Fundy in Nova Scotia.

Tidal current energy, also called ‘in-stream’ or ‘hydrokinetic’ tidal energy, is a different form of tidal power generation that does not require barrages or dams. In constricted ocean channels or inlets, the changing tidal water level can create strong tidal currents. Low-impact tidal current turbines, which and resemble underwater versions of wind turbines, are still under development. Research, development, and capital costs are high since the technology is mostly in the experimental stage, and have borrowed from many advanced in wind energy technology.

Several tidal energy sites are under investigation across the USA. In Washington, the city of Tacoma is investigating the tidal energy potential of the Tacoma Narrows of Puget Sound. The company Verdant Power (www.verdantpower.com) is installing six 36-kW tidal turbines in the East River of New York City, with the installation of the first two turbines to be completed by the end of this year. The six tidal turbines will power a shopping center and parking garage on Roosevelt Island, which is located between the boroughs of Queens and Manhattan.

In Europe, an array of tidal turbines is also being built in northern Norway (www.e-tidevannsenergi.com), with 540 kW of generation capacity to be installed by the end of 2006. Lunar Energy (www.lunarenergy.co.uk), HydroVenturi (www.hydroventuri.com) and Marine Current Turbines (www.marineturbines.com) are three promising tidal current turbine upstart firms from the UK, where the government is very supportive of ocean energy research.

Both wave and tidal energy devices will soon begin tests at the new European Marine Energy Centre (www.emec.org.uk), which is located in the Orkneys Islands north of Scotland. The Scottish government has pledged that the country generate 18% of its power from renewable resources by 2010, and this new marine energy testing center will be the largest such facility in the world.

Alaska has many sites with strong tides along its lengthy coast, including both large tidal ranges between high and low tides, and strong tidal currents. Parts of the Alaska coastline have some of the strongest tides in the world, including the upper Cook Inlet around Anchorage. Bristol Bay, Cordova, Seldovia, Angoon and other locations in Southeast Alaska also have strong tidal currents.

The tidal power potential of Alaska has been studied since the 1950s, although no tidal energy systems yet exist in Alaska. Over the past several decades, a number of tidal energy studies have been conducted on Cook Inlet. All of these proposed the construction of large concrete barrages (seawater dams) and the use of conventional bulb-type, “low-head” hydropower turbines. Various ‘barrage schemes’ for upper Cook Inlet were studied up until the early 1980s.

Tidal Electric of Alaska’s tidal energy feasibility study for Cordova proposed a large, concrete-enclosed ‘tidal tank’, a modification on the traditional tidal barrage, and would have still used conventional bulb-type turbines. A 1998 feasibility study conducted in Cordova estimated a $14 million initial cost for a 5000-kW system, or $2800 per kW of installed capacity. Electricity generated from the nearby 6000-kW Power Creek hydroelectric project, which was completed in 2001, was found be more economical. The Cordova tidal energy studies between 1998 and 2000 were the most recent investigations conducted, though did not lead to any development.

Hydrokinetic or in-stream current energy has only recently been under investigation for use in Alaska. The Underwater Electric Kite Corporation (www.uekus.com) has proposed an in-stream turbine installation for the town of Eagle on the Yukon River, with 270 kW to be installed. This project was first proposed in 2003, though still has not received funding. Next door in British Columbia, the provincial electric utility BC Hydro commissioned a 2002 study on tidal current energy, which concluded that the theoretical tidal current power potential of the BC coast is just over 2200 MW.

Knik Arm has the potential of being a good site for a tidal current power plant, with strong currents four times each day. Also, Elmendorf Air Force Base, on the east side of the arm, has significant electrical infrastructure and demand for power. The site also has a close proximity to the Port of Anchorage, which would serve as a base of operations for both construction and maintenance.

The currents and depth are good for the site, but there is are several other concerns that could derail a project, most importantly concern over marine mammals in Knik Arm. Upper Cook Inlet’s Beluga whale count was low this year, worrying marine biologists. A recent report by the Electric Power Research Institute (EPRI) recommended that ‘Alaskan stakeholders’ commission a studies on sub-surface ice behavior, future trends in seabed movement, conduct a site-specific regulatory and environmental assessment, and more detailed tidal current velocity measurements. Deploying an array of tidal current turbines at the Cairn Point site in Knik Arm could produce an average of 17 MW or power from the tidal currents, enough to power over 10,000 average Anchorage homes.

The Alaska tidal energy rush has already started. One upstart tidal energy developer, the Miami-based Ocean Renewable Power Company (www.oceanrenewablepower.com), has recently applied for preliminary permits with the Federal Energy Regulatory Commission (FERC) at seven Alaska locations. However, they already have a bad reputation within the close-knit tidal energy industry.

If approved, a preliminary FERC permit gives a developer three years exclusive access to a site. In the case of these two firms, it is likely that they only intend to “bank” the sites and auction them off for its own private gain when tidal technology matures a few years down the line. Many in the industry are accusing the Oceana and Ocean Power Renewable companies of blocking access to prime sites by applying for permits with no intention of developing them.

Sean O’Neill, president of a new trade group called the Ocean Renewable Energy Coalition recently told Bloomberg News that “Speculation, and the fact it could hold up a site for anywhere from three to six years, that certainly is not good for the industry… Any company that is banking sites should be tarred and feathered.” So in all likelihood, lawsuits over Alaskan tidal energy sites are quite possible for the near future. For more information, read the Bloomberg News article on the web: (www.renewableenergyaccess.com/rea/news/story?id=45668&src=rss).

Wave Energy

Though often co-mingled, wave power is a diffierent technology than tidal power generation. However, like tidal energy technology, wave power generation is not yet a widely employed technology, with only a few experimental sites in existence. Worldwide, wave power could yield much more energy than tidal power.

The Earth’s total tidal dissipation (friction, measured by the slowing of the planet’s rotation) is 2.5 terawatts, or about the same amount of power that would be gennerated by 2,500 typical nuclear power plants. The energy potential of waves is certainly greater, and wave power can be exploited in many more locations than tidal energy.

Large wave energy potential is estimated for Alaska’s, thousands of miles of coastline, which is more than the length of coast for the other 49 states combined. Some of the most powerful waves in the world are found in Alaska, and the southern Pacific coastal arc of Alaska (stretching from Ketchikan to Attu) has a theoretical wave energy potential estimated to be 1,250 TWh per year, or 300 times more electricity consumed by Alaskans today.

There are a wide variety of wave energy conversion technologies being tested, ranging from “bobbing corks” to giant metal “sea snakes”. The Pelamis Wave Energy Converter is being developed by an upstart wave energy technology company from Edinburgh, Scotland (www.oceanpd.com/default.html ).

Ocean Power Delivery (OPD), developer of the Pelamis device, has secured over $23.6 million of new investment from a consortium of new and existing investors. In May 2005, OPD signed an order with a Portuguese consortium to deliver the initial phase of the world’s first commercial wave-farm. OPD recently delivered the first three production machines to Portugal, where they will be installed following final assembly and commissioning by the end of 2006. The three units are planned to have a total generating capacity of 2.25 MW, or about enough to power a town of 1000 people.

Another upstart wave energy company, the AquaEnergy Group (www.aquaenergygroup.com ), is working on a four-“bouy” installation with one MW of capacity, to be located three miles offshore of Makah Bay, Washington. The wave energy upstart Ocean Power Technologies (www.oceanpowertechnologies.com ) has already deployed its PowerBouy in Hawaii and New Jersey, and is planning an installation in northern Spain. Other wave power generation projects are under development off the coasts of Italy, Spain, South Africa and Oregon.

The Future for Ocean Energy in Alaska

Knik Arm is the most promising commerical tidal energy site in the state, due to its close proximity to Anchorage. Also, offshore wind or tidal turbines mounted on abandoned oil and gas platforms in Cook Inlet, though new underwater electric transmission cables would be needed. To find more promising sites, a statewide study of Alaska’s tidal and wave energy potential is needed. In the future, utility-scale tidal power could also help the urban Alaska energy situation, which is faced with looming increases in natural gas prices. Tidal energy research and development in Alaska could establish the state as a world leader in ocean power technology.

Given the length of its coastline and the strength of the seas, both wave and tidal energy are well worth exploring for Alaska’s future energy needs

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