Posts Tagged ‘UK’

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.


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.


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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MendoCoastCurrent, August 4, 2009

oyster_prototype_device_aquamarine_powerOyster nearshore wave energy technology from Aquamarine Power is in the process of being placed on the seabed in the Atlantic off the coast of the Orkney Islands, Scotland for trials in autumn 2009.

The Oyster is based on a large, hydraulic oscillator fitted with pistons and activated by waves.  The oscillation pumps pressurized water through a pipeline to the shore.  Onshore, conventional hydro-electric generators convert the high-pressure water into electricity.

The concept is based on research from Queen’s University in Belfast. “Oyster’s technology is highly innovative because it relies on simplicity,” says Ronan Doherty, CTO at Aquamarine Power.

“Its offshore component – a highly reliable flap with minimal submerged moving parts – is the key to its success when operating in seas vulnerable to bad weather where maintenance can be very difficult.”  Doherty adds that as there is no underwater generator, electronics or gearbox and all the power generation equipment in onshore, where it is easily accessible.

Oyster technology is best deployed in near-shore regions at depths of 26-52 feet, where wave action tends to be more consistent and less variable in direction. The smaller size of waves near the shore also maximizes the lifetime of the device and the consistency of power generation. Each Oyster has a peak capacity of 300-600 kW but is designed to be deployed in multiple arrays.

Although still in the early stages of development, Aquamarine Power believes Oyster has great potential. “Our computer modeling of coastlines suitable for this technology shows that Spain, Portugal, Ireland and the UK are ideal candidates in Europe,” says Doherty. “But globally there is huge scope in areas like the Northwest coast of the U.S. and coastlines off South Africa, Australia and Chile.”

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STEPHEN IVALL, Falmouth Packet UK, June 27, 2009

SWMTF-wave-energy-buoyThe ambition for Cornwall to become a world-leading centre for wave energy has moved a step closer to reality with the launch of a two-tonne (2000kg) buoy off the coast of Falmouth.

Developed by a team at the University of Exeter, the South Western Mooring Test Facility (SWMTF) buoy is a world first. It will gather detailed information to help inform the future design and development of moorings for marine energy devices.

It will complement the South West RDA’s (Regional Development Agency) Wave Hub project, which will create the world’s largest wave energy farm off the north coast of Cornwall. It also supports wider ambitions to make the South West a global centre of excellence for marine renewables.

The SWMTF is the latest development from PRIMaRE (the Peninsula Research Institute for Marine Renewable Energy), a joint £15 million institute for research into harnessing the energy from the sea bringing together the technology and marine expertise of the Universities of Exeter and Plymouth.

Led by Dr Lars Johanning, the PRIMaRE mooring research group at the University of Exeter successfully developed the £305,000 SWMTF with capital investment from the ERDF Convergence programme matched with funds from the South West RDA. The research team is part of the University of Exeter’s Camborne School of Mines, based on the Tremough Campus, Penryn.

The SWMTF buoy has been designed with unique features so it can obtain very detailed data in actual sea conditions to show how moored structures respond to changes in wind, wave, current and tide. Using this information, developers will be able to model and test mooring designs and components for their marine energy devices as they convert wave movement into energy. The SWMTF will also provide data for a wide range of other marine devices.

The SWMTF buoy has a simple, circular design, with specialised sensors and other instruments built into its structure, enabling it to record data to a high degree of accuracy and allow real time data communication to shore. It has taken a year to develop the buoy and its instruments. Most of the components were manufactured by companies in the South West, many of which are in Cornwall.

Dr Lars Johanning of the University of Exeter said: “This is a major milestone in PRIMaRE’s research and we are excited about the potential this might have for the development of the Wave Hub project. It has been a huge challenge to build something that can function in the unpredictable environment of the open sea. This would not have been achieved without the design effort provided by the PRIMaRE project engineers Dave Parish and Thomas Clifford, and the many companies who have risen to the challenge to manufacture the buoy and its instruments. We look forward to announcing the results of our tests after the first set of sea trials.”

Nick Harrington, head of marine energy at the South West RDA, said: “We are investing £7.3 million in PRIMaRE to create a world-class marine renewables research base as part of our drive towards a low-carbon economy in the South West, and this buoy will help technology developers design safe but cost-effective moorings. Our groundbreaking Wave Hub project which is on course for construction next year will further cement our region’s reputation for being at the cutting edge of renewable energy development.”

Now that the buoy has been launched, the team will conduct the first tests, within the secure location of Falmouth Harbour. The buoy will then be moved to its mooring position in Falmouth Bay. Once moored at this location, data will be transmitted in real time to a shore station for analysis. A surveillance camera will transmit images to the PRIMaRE web page, allowing the team to continually monitor activities around the buoy.

The SWMTF buoy also has the potential to support other offshore industries, including oil and gas or floating wind installations, in the design of mooring systems. Discussions are already underway with instrumentation developers to develop specific underwater communication systems. In addition the development of the SWMTF buoy has helped secure funding for a collaborative European FP7-CORES (Components for Ocean Renewable Energy Systems) programme, taking the University of Exeter to the forefront of European wave energy converter research.

PRIMaRE will also play a strategic role in the Environmental and Sustainable Institute (ESI), which the University of Exeter aims to develop at the Tremough Campus.

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PETER ASMUS, Pike Research, June 17, 2009

wave-ocean-blue-sea-water-white-foam-photoThe earth is the water planet, so it should come as no great surprise that forms of water power have been one of the world’s most popular “renewable” energy sources. Yet the largest water power source of all – the ocean that covers three-quarters of earth – has yet to be tapped in any major way for power generation. There are three primary reasons for this:

  • The first is the nature of the ocean itself, a powerful resource that cannot be privately owned like land that typically serves as the foundation for site control for terrestrial power plants of all kinds;
  • The second is funding. Hydropower was heavily subsidized during the Great Depression, but little public investment has since been steered toward marine renewables with the exception of ocean thermal technologies, which were perceived to be a failure.
  • The third reason why the ocean has not yet been industrialized on behalf of energy production is that the technologies, materials and construction techniques did not exist until now to harness this renewable energy resource in any meaningful and cost effective way.

Literally hundreds of technology designs from more than 100 firms are competing for attention as they push a variety emerging ocean renewable options. Most are smaller upstart firms, but a few larger players – Scottish Power, Lockheed Martin and Pacific Gas & Electric — are engaged and seeking new business opportunities in the marine renewables space. Oil companies Chevron, BP and Shell are also investing in the sector.

In the U.S., the clear frontrunner among device developers is Ocean Power Technologies (OPT). It was the first wave power company to issue successful IPOs through the London Stock Exchange’s AIM market for approximately $40 million and then another on the U.S. Stock Exchange in 2007 for $100 million. OPT has a long list of projects in the pipeline, including the first “commercial” installation in the U.S. in Reedsport, Oregon in 2010, which could lead to the first 50 MW wave farm in the U.S. A nearby site in Coos Bay, Oregon represents another potential 100 MW deployment.

While the total installed capacity of emerging “second generation” marine hydrokinetic resources – a category that includes wave, tidal stream, ocean current, ocean thermal and river hydrokinetic resources – was less than 10 MW at the end of 2008, a recent surge in interest in these new renewable options has generated a buzz, particularly in the United Kingdom, Ireland, the United States, Portugal, South Korea, Australia, New Zealand and Japan, among other countries. It is expected that within the next five to eight years, these emerging technologies will become commercialized to the point that they can begin competing for a share of the burgeoning market for carbon-free and non-polluting renewable resources.

The five technologies covered in a new report by Pike Research are the following:

  • Tidal stream turbines often look suspiciously like wind turbines placed underwater. Tidal projects comprise over 90 percent of today’s marine kinetic capacity totals, but the vast majority of this installed capacity relies upon first generation “barrage” systems still relying upon storage dams.
  • Wave energy technologies more often look more like metal snakes that can span nearly 500 feet, floating on the ocean’s surface horizontally, or generators that stand erect vertically akin to a buoy. Any western coastline in the world has wave energy potential.
  • River hydrokinetic technologies are also quite similar to tidal technologies, relying on the kinetic energy of moving water, which can be enhanced by tidal flows, particularly at the mouth of a river way interacting with a sea and/or ocean.
  • Ocean current technologies are similar to tidal energy technologies, only they can tap into deeper ocean currents that are located offshore. Less developed than either tidal or wave energy, ocean current technologies, nevertheless, are attracting more attention since the resource is 24/7.
  • Ocean thermal energy technologies take a very different approach to generating electricity, capturing energy from the differences in temperature between the ocean surface and lower depths, and can also deliver power 24/7.

While there is a common perception that the U.S. and much of the industrialized world has tapped out its hydropower resources, the Electric Power Research Institute (EPRI) disputes this claim. According to its assessment, the U.S. has the water resources to generate from 85,000 to 95,000 more megawatts (MW) from this non-carbon energy source, with 23,000 MW available by 2025. Included in this water power assessment are new emerging marine kinetic technologies. In fact, according to EPRI, ocean energy and hydrokinetic sources (which includes river hydrokinetic technologies) will nearly match conventional new hydropower at existing sites in new capacity additions in the U.S. between 2010 and 2025.

The UN projects that the total “technically exploitable” potential for waterpower (including marine renewables) is 15 trillion kilowatt-hours, equal to half of the projected global electricity use in the year 2030. Of this vast resource potential, roughly 15% has been developed so far. The UN and World Energy Council projects 250 GW of hydropower will be developed by 2030. If marine renewables capture just 10% of this forecasted hydropower capacity, that figure represents 25 GW, a figure Pike Research believes is a valid possibility and the likely floor on market scope.

The demand for energy worldwide will continue to grow at a dramatic clip between 2009 and 2025, with renewable energy sources overtaking natural gas as the second largest source behind coal by 2015 (IEA, 2008). By 2015, the marine renewable market share of this renewable energy growth will still be all but invisible as far as the IEA statistics are concerned, but development up to that point in time will determine whether these sources will contribute any substantial capacity by 2025. By 2015, Pike Research shows a potential of over 22 GW of all five technologies profiled in this report could come on-line. Two of the largest projects – a 14 GW tidal barrage in the U.K. and a 2.2 GW tidal fence in the Philippines — may never materialize, and/or will not likely be on-line by that date, leaving a net potential of more than 14 GW.

By 2025, at least 25 GW of total marine renewables will be developed globally. If effective carbon regulations in the U.S. are in place by 2010, and marine renewable targets established by various European governments are met, marine renewables and river hydrokinetic technologies could provide as much as 200 GW by 2025: 115 GW wave; 57 GW tidal stream; 20 GW tidal barrage; 4 GW ocean current; 3 GW river hydrokinetic; 1 GW OTEC.

About the author: Peter Asmus is an industry analyst with Pike Research and has been covering the energy sector for 20 years. His recent report on the ocean energy sector for Pike Research is now available, and more information can be found at http://www.pikeresearch.com. His new book, Introduction to Energy in California, is now available from the University of California Press (www.peterasmus.com).

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EnergyCurrent, June 11, 2009

13298_DIA_0_opt picOcean Power Technologies Inc. (OPT) has reached two major manufacturing milestones in the development of the company’s PB150 PowerBuoy, a wave energy converter that is to be ready for deployment at the European Marine Energy Centre (EMEC) in Scotland by the end of 2009.

The mechanical elements of the power take-off system of the PB150 have been completed. OPT has also awarded Isleburn Ltd. the steel fabrication contract for the PowerBuoy structure. Isleburn is an Inverness, Scotland-based fabrication and engineering company for offshore structures.

Once the steel fabrication is complete, the 150-kW PowerBuoy will be fully assembled and ready for deployment by the end of 2009 at EMEC, where OPT has already secured a 2-MW berth.

When the PowerBuoy has been fully demonstrated at EMEC, OPT intends to deploy further PB150 PowerBuoys in projects around the world at locations including Reedsport, Oregon; Victoria, Australia and Cornwall, U.K.

OPT CEO Mark R. Draper said, “These two milestones demonstrate significant progress towards the deployment of OPT’s first PB150. This achievement represents a pivotal stage in the company’s development and that we are on track to achieve our objective of utilizing wave power as an economically-viable source of renewable energy.”

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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.


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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MendoCoastCurrent, March 25, 2009


Aquamarine Power has signed a $2.7 million contract with Fugro Seacore to install their wave energy generator, the Oyster, at the European Marine Energy Center.

Aquamarine’s Oyster converter is designed for waters that are from 26-52 feet deep with anticipated installation 550 yards offshore in the second half of 2009.  The Oyster has a wave action pump sending pressured water in a pipeline to an electricity generator.

The generator, to be built in Orkney, Scotland, is expected to produce between 300 and 600 kilowatts for Scotland’s national grid.

The contract is part of the Scottish government’s goal to derive 50% its electricity from renewable energy sources by 2020.

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