Alstom and SSE Renewables have signed a new joint venture agreement to co-develop the world’s largest wave farm in the Costa Head Wave Project, off the coast of Orkney, Scotland. The farm will deliver up to 200 Megawatts of renewable energy utilizing AWS Ocean Energy Ltd’s (AWS) Archimedes Wave Swing III technology (AWS-III).

AWS is based in Inverness, Scotland, and the company’s stated purpose is to develop and deliver the technology of choice for utility scale generation of offshore wave power.

AWS-III is described in U.S. Patent Application Publication No. 2011/0185721, entitled “Energy Conversion Device” (’721 Application) and directed to an array of interconnected compressible cells which convert wave energy into pneumatic energy by moving air between the cells. Turbines within the device convert the moving air into electricity.

Figure 1 of the ’721 Application illustrates the wave energy device. The device has twelve interconnected cells (20) arranged in a ring. The cells are connected to a ring-like air duct (not shown) and have a diaphragm (30) on their outer edge.

The diaphragm moves relative to the cell when wave action (40, 50) presses against the movable diaphragm surface. The movement of the diaphragm causes air within the cells to be pumped into and out of the air duct and between the cells. The moving air then spins a turbine, which produces electricity.

Each multi-cell array can produce up to 2.5 megawatts of electricity. Once in place, the devices are moored to the sea floor in depths ranging from 60 – 150 meters. Each device will be connected to the local utility grid from an offshore substation via a high voltage link.

According to a joint press release, a 1:9 scale model of the AWS-III was deployed in Loch Ness, Scotland in 2010. Full scale component testing will commence in 2012 and a full scale prototype is planned for deployment in 2014.

In the press release, Simon Grey, Chief Executive at AWS stated:

The selection of the AWS-III system for this exciting and ground-breaking project is a significant endorsement of our technology and team. We firmly believe that the AWS-III will become the established choice for utility scale offshore wave power generation. We look forward to working with Alstom and SSE to deliver Costa Head.

AWS and Alstom predict there is a potential worldwide market for renewable wave energy in the 200 to 300 gigawatt range. If successful, this 200 megawatt wave farm will be a large step in making that prediction a reality.

Article by David Gibbs, appearing courtesy Green Patent Blog.

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According to a new study by the Carbon Trust up to 240 GW of capacity of marine energy could be installed worldwide by 2050. Out of these, 75 percent could be coming from wave, and the remainder by tidal energy.

The total market for both wave and tidal energies could in a high scenario amount to up £460 billion (520 billion euros or 740 billion USD) over the next decades.

Similarly, the global market could be worth £40 billion (45 billion euros or 65 billion USD) per annum by 2050.

This explains why according to New Scientist, up to a hundred companies are developing devices in this sector.

However, the study warns that only modest deployment could be achieved by the end of this decade. Indeed uncertainty remains high over the various designs and governmental policies.

The study also warns that depending on various factors such as demand-reduction measures, the success of other low carbon sources and technological development, the risk of very little deployment – and even “zero” deployment – remains high.

But what are exactly these energy sources? Here is a quick explanation :

• Wave energy captures the movement of surface water thanks to wind. The longer the distance, the greater the transfer of energy to waves ;
• Tidal energy converts the energy of tides to electricity. Devices used for this are similar to wind turbines, but underwater.
• Ocean Thermal Energy Conversion (OTEC) is the third energy source from oceans. It wasn’t covered by the study.

Marine energies offer various advantages over other renewables:

• Production is near consumption as half the global population lives near the coasts ;
• Predictable as the hours of tides are known in advance ;
• Silent, unlike wind turbines ;
• Invisible, unlike all other renewable energy sources.

As a Frenchman I am proud to note that our country developed as early as 1963 the first tidal power plant in La Rance. Connected to the grid in 1967, it provides 600 GWh per annum ever since thanks to  its 240 MW capacity. It has been for decades the largest of its kind in the world.

As I noted previously : With less than 10 MW currently installed, experts believe installed power could reach a GW in only six years.

To conclude, it is also worth noting that wave energy could provide up to 10 percent of the United States’ electricity.

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PG&E, Pacific Gas and Electric, provides electricity and natural gas to roughly 40 percent of all Californians. Because this equates to approximately one out of 20 Americans, PG&E recognizes the products that are produced and delivered to serve customers has an impact on the environment. Because of this, PG&E has an environmental commitment extending beyond normal compliance, and including all sectors of the business, including the delivering of clean electric power and the regulation of greenhouse gas emissions.

1) Solar Schools Program. The PG&E Solar Schools program educates K-12 students in Central and Northern California on the importance of energy efficiency and renewable energy. By making the school buildings hands-on science experiences, the Solar Schools program provides a way to make science much more interesting as well as educate students on how they can positively affect the environment. Schools involved with the program are outfitted with photovoltaic systems and receive a solar-based curriculum training package and workshops.

2) PG&E Solar Habitat Program. The PG&E Solar Habitat Program is a partnership between the energy company and Habitat for Humanity International for the funding of the entire cost of solar electrical systems on all Habitat-build homes throughout Central and Northern California. This is the first type of partnership that provides solar energy to limited income families, which furthers the PG&E objective to provide affordable renewable energy throughout the California community. Since the establishment of the program in 2005, PG&E provided over $2 million to Habitat for Humanity affiliates in California to build the solar installations.

3) Deal between PG&E and AT&T Park, Home of the San Francisco Giants. PG&E along with AT&T Park, home of the San Francisco Giants, has partnered up to make it the greenest ballpark throughout the United States. Through this partnership, the AT&T Park became the first ballpark to achieve Silver LEED status in 2010. One of the largest sustainability projects undertaken was the installation of 600 solar photovoltaic panels. Another large project was the installation of the Diamond Vision scoreboard, which utilizes 78 percent less energy than the original scoreboard at the ballpark.

4) PG&E Food Service Technology Center. The PG&E Food Service Technology Center provides energy efficiency consulting services to the commercial food service industry, including restaurant owners and operators, institutional food service providers, kitchen designers, and cooking equipment manufacturers. This center offers advice on a number of areas, including kitchen equipment test reports, design consultation services to allow business owners to design and get equipment that operates at maximum efficiency, on-site facility surveys to find ways to reduce energy, educational seminars on energy performance in kitchens, and equipment testing services to discover performance and energy characteristics of the equipment.

5) PG&E SmartMeter Technology. The SmartMeter Technology created by PG&E is installed into homes and will help in upgrading the energy infrastructure of California via automated metering technology. The technology will allow for new programs that will assist PG&E energy customers with using less energy, becoming more energy efficient and saving money off the cost of their energy bills per month. According to the website, “The SmartMeter system uses programmable solid-state meter technology that provides two-way communication between the meter at your home or business and the utility, using secure wireless network technology.”

6) PG&E Launches New Major Solar Energy Initiative. In April of 2010, PG&E made plans to begin the implementation process of a new solar photovoltaic program approved by the California Public Utilities Commission. When the program is compete, approximately 500 megawatts of clean energy will be produced, meeting the needs of an estimated 150,000 homes throughout the Northern and Central California PG&E service center. This is a five year initiative that will assist in providing more customers with direct access to solar power and create a number of new green jobs.

7) PG&E ClimateSmart Program. The PG&E ClimateSmart Program allows business owners and homeowners to lower the amount of carbon dioxide emissions from their office or home through environmental conservation. When someone joins the ClimateSmart Program, a tax deductible amount is added to the PG&E bill based on the energy use by the home or office for that month. The money then goes to carbon dioxide emissions reduction and capture products, including native redwood forest restoration and capturing methane gas from landfills and dairy farms.

8 ) Greening Vehicles Initiatives. For more than two decades PG&E has helped the push toward cleaner, efficient vehicles. PG&E itself have used their own vehicles to promote the pioneering use of alternative fuels to reduce carbon dioxide emissions and lower the dependency on fossil fuels. Currently, PG&E integrates a variety of vehicle technologies in its own fleet, including focus on natural gas vehicles and bio-diesel fuels. In recent times, PG&E has been able to develop as well as incorporate a number of electric vehicles into their fleet along with a number of other high efficiency technologies. In the last year, for example PG&E added the first all electric bucket truck to the fleet, plus a number of plug-in hybrid electric and hybrid diesel electric vehicles.

9) PG&E Partners with BrightSource for Solar Power Deal in 2009. PG&E announced in 2009 that it was partnering with BrightSource Energy, Inc for a deal that would produce 1,310 megawatts of solar thermal power in seven different projects. The first of the solar power plants will be built in Ivanpah, California and provide 110 megawatts of electricity. The plans to begin operation are in 2012. In total, all seven projects will provide enough energy for the annual consumption of approximately 530,000 average family homes. “The solar thermal projects announced today exemplify PG&E’s commitment to increasing the amount of renewable energy we provide to our customers throughout northern and central California,” said John Conway, senior vice president of energy supply for PG&E. “Through these agreements with BrightSource, we can harness the sun’s energy to meet our customers’ power requirements when they need it most – during hot summer days.”

10) WaveConnect. By studying the potential of ocean wave energy as part of California’s overall energy future, PG&E is looking to explore the overall feasibility of utilizing wave energy because of its large potential as a renewable, carbon dioxide free electricity generating power and can become a major contributor to renewable energy in the state. WaveConnect is PG&E’s wave energy conversion technology developed to capture the energy waves make.

Article by Shawn Lesser, Co-founder & Managing Partner of Atlanta-based Watershed Capital Group – an investment bank assisting sustainable fund and companies raise capital, perform acquisitions, and in other strategic financial decisions. He is also a Co-founder of the GCCA Global Cleantech Cluster Association ”The Global Voice of Cleantech”. He writes for various cleantech publications and is known as the David Letterman of Cleantech for his “Top 10″ series. He can be reached at shawn@watershedcapital.com

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The ARPA-E Energy Innovation Summit took place last week just outside Washington, D.C., and the show floor was filled with projects that promise to advance the United States as a force in clean energy. Most of the exhibiting companies were very young and in possession of early-stage technologies that are difficult to explain. But a few offered a clear glimpse of the future.

A little background: ARPA-E (Advanced Research Projects Agency – Energy) is a new federal agency created by the Obama administration and originally funded with money from the 2009 stimulus package. It is the Energy Department’s answer to DARPA, the military’s extraordinarily successful research program that formed the basis for the stealth fighter, GPS and the Internet. ARPA-E is funding environmentally-friendly solutions like smart buildings, carbon capture from coal plants, electrofuels and improved solar and wind power.

1. Printable LED Lights: Nth Degree Technologies
At the summit, Nth Degree Technologies made the debut of what it calls Printed Illuminated Paper. The company embeds paper with thousands of tiny LEDs, each the size of a white blood cell, to make sheets of light that can be cut to any shape or size.

The company had two kinds of demos on hand: One was two light bulbs, or rather pieces of illuminated paper cut into the shape of light bulbs. (See the video.) However, Mark Lowenthal, the company’s vice president, told me that these were just attention-grabbers and that the final product will be based on a different technology and will bear more resemblance to the piece of paper in the photograph to the right. This light was far brighter and used 8 watts of electricity. The next generation of illuminated paper, Lowenthal said, will consume a quarter the wattage and be 50 to 100 times brighter.

2. Trapping the Ocean’s Power: Atmocean, Inc.
The idea behind the Atmocean WEST (Wave Energy Seawater Transmission) is to deploy an array of oceanborne devices that capture wave energy and store it for later use, all while creating better fishing grounds. How is such a trifecta possible?

WEST creates its power from a sort of tug-of-war. A series of buoys (the yellow items in the graphic) float on the surface. Underwater, each buoy has a tail equipped with a series of toggles that creates a huge amount of drag. Between the buoy and the tail is a pump that is activated with each passing swell. That pump sends seawater through a hose to a central floating platform, where it operates an air compressor. That compressor, in turn, routes through a hose to the ocean floor, where the air is stored in bladders.

Those bladders are the invention of an ARPA-E awardee, Bright Energy Storage Technologies. (Atmocean isn’t an awardee, by the way, but was one of several companies whose presence on the show floor was a tacit endorsement by ARPA-E.) Bright Source has realized that air, trapped in the pressurized environment of deep water, is an efficient way to store energy. A pneumatic tube connects the bladder to shore, where the air expands in volume and can be released to spin a turbine whenever the energy is needed.

Now about that fishing thing: Atmocean’s CEO, Philip Kithil, told me that his initial tests have shown that the toggle-and-buoy system creates an upwelling of cold water, which if it were borne out would make the area around the buoys into a nutrient-rich ground for fish.

3. Refrigeration Anywhere: Xergy Inc.
Xergy uses the principles of a fuel cell to create cooling in a much smaller space than a traditional air conditioner, while consuming a fraction of the power and without using refrigeration fluids that are harmful to the atmosphere. “We are using hydrogen as a working fluid and pumping it across a membrane using electricity,” says Bahmad Bahar, the company’s president and an Iranian engineer who grew up in the family’s refrigeration business.

The company was a finalist in ARPA-E’s BEETIT (Building Energy Efficiency Through Innovative Thermodevices) category and is a finalist in GE’s Ecoimagination contest.

With no moving parts and a simple design, Bahar thinks Xergy’s air conditioners could be scaled to cool an environment of almost any size, from a computer’s CPU to a full-size building. And since it takes up less space, a unit could be inserted where air conditioners have never gone before, like the wall of a building or the door panel of a car.

4. Storing Sun and Wind Energy: General Compression
One of the biggest problems with renewable energies like wind and solar is that the sun doesn’t always shine and the wind doesn’t always blow. General Compression is one of several companies funded by ARPA-E that is figuring out how to take these intermittent sources and make them into something that can provide “baseload power” that is available 24/7.

When the wind blows or the sun shines, a renewable-energy plant often produces more electricity than the grid can presently use. General Compression takes that extra power and uses it to make compressed air, which is stored in a salt cavern underground. Then, when night falls or the wind dies, the air can be released to spin turbines and create electricity.

There’s just one problem. When that stored air is released, or un-compressed, it becomes so cold that it’s difficult to handle. Other companies contend with this problem by burning some fossil fuels to heat the air. General Compression’s answer is to trim the cold temperatures (and also the heat from the initial compression) by venting it to a pool of water on the surface.

Article by David Ferris, appearing courtesy the Matter Network.

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As a country with enormous potential for both wind power and solar energy, India has been steadily working towards building up the respective technologies to establish their renewable energy reputation. One of the areas they have yet to consider, however, is tidal and wave based energies and India is about to make a change for the better in that department. With plans to have a tidal power station built in the country within the next couple of years, the nation is ready to grab the title of the first Asian nation to host tidal power.

The tidal power plant that is being planned for India is currently expected to provide a capacity of fifty megawatts of renewable energy with the potential to be expanded up to a larger 250 megawatt capacity. The plant is to be built by the Atlantis Resources Corporation, which is a London based renewable energy company, and located in the Gulf of Kutch in the Indian state of Gujarat. Atlantis believes that the plant, while currently expected to reach the 250 megawatt capacity, is capable of attaining a 300 megawatt maximum capacity. They also believe the area might be suitable for offshore wind power at some point in the future.

With the location and specifications decided, the tidal power plant that is to become the first commercial plant in Asia is to be part of a memorandum of understanding that will allow the company to build the plant and sell the electricity. The electricity purchased from the plant is going to be going to the Gujarat Power Corporation under a variety of tariffs that have not yet been fully determined. Currently, Atlantis and the local government are hoping that the plant will be fully operation come 2013.

Though the plant being built in India is the first commercial tidal power plant in Asia, it is not Atlantis Resources’ first bout with the technology. The company is currently working on projects off the coast of Scotland, where it is believed that immense tidal power potential is readily available, and in various locations in Australia. With the Indian venture added to their portfolio, Atlantis has plenty of chances to prove the worth of tidal power.

Given the exciting potential that tidal power holds, it is nice to see India ready to take the plunge and invest is what is one of the more expensive renewable energy ventures in the world. With any luck, however, the leap of faith will prove not only profitable, but beneficial on the green side, and convince neighboring nations to give it a try.

Article by Richard Cooke, appearing courtesy Justmeans.

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Wave energy technology is one of the more fascinating renewable energy technologies that are being researched today. In concept, they bear a similarity to how wind power works by harnessing a naturally occurring movement and transfer of energy in order to generate electricity. Sadly, a great deal of wave energy projects so far have had varying degrees of success or failure and many believe that the technology just isn’t where it needs to be for wave energy technology to make a difference. Now, off the coast of Florida, one group of researchers have been striving to make wave energy technology a viable reality.

Clean and Green Enterprises, a renewable energy company based out of Tallahassee, Florida, has been working with researchers from the Florida Institute of Technology’s College of Engineering to develop what they call Wing Waves. The design, which is about five years in the making, works in a way similar to a fan once they’ve been placed on the sea floor and start moving along with the rhythm of the waves. According to the people behind the project, the sea wings should be ideally placed in an area with a smooth, sandy sea floor and in roughly forty to fifty feet of water. Since they do not require any elaborate means of operating, the researchers have said that the Wing Waves do not have any negative effects on the ocean life in the area and have been, so far, attracting the local fish.

The Wing Waves are designed to generate a pretty substantial amount of renewable energy once they have been deployed in a way that maximizes their efficiency. According to Stephen Wood, a member of the research team, the Wing Waves can generate enough electricity to power nearly 200,000 homes when placed in a square mile set up that is comprised of roughly 1,000 units. The way the Wing Waves work is that they flap back and forth at a thirty degree angle, taking about eight to ten seconds to complete a cycle, and shut down in excessive conditions. By shutting down, they prevent damage being done to the system by too much wave energy. The current design of the Wing Waves puts them at eight feet tall and fifteen feet wide and is using aluminum components in the current prototype model.

The first Wing Waves prototype is due to be raised from the ocean floor sometime this week so that the team can determine just how effective it operated. Once installed in a full capacity, they believe that the models will be able to last roughly twenty years before requiring a replacement. Though it may be a little early to tell just how far the team will be able to go with the Wing Waves, things are certainly looking up. With any luck, maybe in a few years Florida will become the newest site for wave energy in the United States.

Article by Richard Cooke, appearing courtesy Justmeans.

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A U.S. startup is working on a plan to install hundreds of 40-kilowatt hydrokinetic turbines, each the size of a large jet engine, along the bottom of the Mississippi River, an ambitious renewable energy project developers say could someday produce more than one gigawatt of electricity — enough to power 250,000 homes.

While the technology remains relatively unproven, the U.S. Federal Energy Regulatory Commission recently granted the company, Free Flow Power, preliminary rights to explore the potential for dozens of turbine locations along the 2,320-mile river.

Although most efforts to develop hydrokinetic energy projects so far have focused on tidal or wave energy, the company says river installations have significant advantages. “The water flows in one direction, it doesn’t have salt in it, and, in the case of the Mississippi, people have spent 100 years tracking water flows and velocities,” said Henry Dormitzer, the company’s chief financial officer.

The challenges, however, will be to show that the turbines will not impact marine life or the massive volume of traffic on the river. The only commercial hydrokinetic river project currently in use is a single turbine installed on the Mississippi by Texas-based Hydro Green Energy near Hastings, Minn.

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As renewable energy moves steadily into the future, the possibilities that exist thanks to tidal and wave energy are becoming more and more widely accepted by countries hoping to adopt such technologies. While tidal and wave based projects are found around the globe, Europe has been home to several for example, the United States has traditionally preferred to avoid such projects in favor of wind and solar based energies. However, considering the amount of locations found within the United States, particularly in the Northeast, that have been found to be perfectly suitable for tidal or wave projects, it falls now to those supporting the renewable energy type to gain support and push for the testing and installation of the technology.

In Massachusetts, one such group has been formed between researchers from the University of Massachusetts at Dartmouth and various state officials to promote tidal and wave based renewable energy in an area south of nearby Martha’s Vineyard. The idea is to use a tract of ocean to create a sort of testing area for offshore renewable energy technology companies that would allow them to work with their equipment. First proposed in 2008, the area would be approximately twenty seven square miles of ocean and seafloor that has been deemed suitable for renewable energy projects. Massachusetts state officials believe that by founding this research and development area, they will be making the state the leader in offshore, wave, and tidal based renewable energy development in the United States.

There has been some concern by critics of the project that the research and development project could permanently damage the nearby fishing industry. They believe that all of the testing that will be going on after the area has been established could have negative effects on nearby fish ecosystems. Similar concerns over a project in New Hampshire eventually led to the state officials cutting their support for a wave and tidal renewable energy project. If the assessments do not go as well as many believe they will, this project could have the same fate. The leaders of the project are hoping to being work on the area in full sometime next year after the battery of assessments are completed that they believe will ensure that the area will not be detrimental to the local ecosystem or currently existing shipping and fishing businesses.

The project is both being led and receiving support from the New England Marine Renewable Energy Center that consists of several New England based universities and organizations with interests in offshore renewable energy. So far, the organization has received nearly $750,000 for the establishment of the Martha’s Vineyard project and is likely to receive more Department of Energy based grants as the project continues. With the researchers and state officials ready to go ahead, it is only a matter of time before the Northeastern United States becomes a hotbed of offshore renewable energy. With the sizable offshore wind farms already undergoing research or construction, the addition of tidal and wave based renewable energy would be welcome indeed.

Article by Richard Cooke, appearing courtesy Justmeans.

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The news that the world’s largest tidal turbine – 1 MW in size – will be installed off the coast of Scotland near Orkney should come as no surprise.

Primitive tidal mills operated in the England date back to the 11th century. During the 18th century, several tidal mills popped up in Western Europe. The first modern tidal plants borrowed from conventional hydropower concepts by relying upon dams or barrages. La Rance, France still boasts the largest such system in the world, supplying 240 MW of capacity since 1966.

Scotland is the hot spot for tidal power in all of northern Europe, with the Pentland Firth often described as the “Saudi Arabia of tidal power.” The U.K. and Ireland also feature among the best tidal sites in the world, because they are relatively close to people. Some from these islands near the European coast may argue with this assessment, but when compared to the U.S. — where 95% of the nation’s tidal resources rise and fall off the coast of remote Alaska — it becomes clear it is all a matter of perspective.

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 (see forecast below.)

Pike Research will be issuing a revised forecast of ocean energy technologies next year, with lower capacity totals given the lack of progress on carbon regulations and the lingering recession, but this 2009 forecast shows how tidal systems dominate the near-term market for ocean energy technologies.

What is the scientific basis of tides?

Tides result from the gravitational forces of the moon and sun interacting with oceans. (Because of its proximity to the earth, the moon actually exerts about twice as much influence on tidal patterns as the sun.) The ever-changing relationship between the moon, sun, and earth causes the ocean to rise and fall at regular intervals. These bulges are frequently referred to as “semi-diurnal” tides.

These tidal streams become concentrated pools of kinetic energy ideal for power generation, when passing through narrow channels, an inlet into a bay or other passages between two land masses. While the tidal resource is much less abundant than wave energy resources, its power density is greater. Most waves move at the pace of approximately one meter per second; tides typically move at least twice that speed at two meters per second. A doubling of the speed of tidal streams will result in eight times the amount of potential energy since power density is determined by the cube of water speed.

The Electric Power Research Institute has projected that a 100 MW tidal stream turbine project could generate power at a cost of 6 to 9 cents per kilowatt hour, which is competitive with wind, geothermal and other mainstream renewable technologies.

The basic selling points for tidal as follows:

• Tidal resources have the highest power density of any of the marine renewable technologies, hence the lowest cost estimates.

• Unlike many renewable resources including solar and wind power, tidal resources can be accurately predicted literally years in advance.

• Tidal devices are typically sited below the ocean surface: they can’t be seen; can’t be heard; and, in most instances, would not interfere with shipping or other maritime uses.

While physics is on the side of tidal streams if compared to wave energy resources, the size of the resource is much smaller. Most experts estimate the wave resource to be two to three times the size of the world’s tidal stream resource.

Article by Peter Asmus, appearing courtesy Matter Network.

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An Irish university has launched the world’s largest hydro-electric wave energy converter off the coast of northern Scotland.

The so-called Oyster is a mechanically-hinged flap that is embedded into the sea floor — at a depth of about 32 feet (10 meters) — and moves with the motions of the waves. That wave energy pumps high-pressure water to a shore-based electric turbine.

Power will be fed into the national grid and provide electricity to homes in the Orkney islands. Researchers say a farm of 20 Oysters could eventually provide enough electricity to power 9,000 three-bedroom homes.

The technology was developed by Queen’s University Belfast and Scotland-based Aquamarine Power Ltd.

“Devices such as these have the power to revolutionize the world’s energy industry and help combat climate change,” said Trevor Whittaker, professor in the Queen’s School of Planning, Architecture and Civil Engineering and lead investigator for the project.

School officials say wave and tidal power could one day provide 20 percent of the UK’s energy needs.

VIDEO: The mechanically-hinged flap, which is embedded into the sea floor at a depth
of about 32 feet (10 meters), moves with the motions of the waves. That wave energy pumps
high-pressure water to a shore-based electric turbine.

Article appearing courtesy of Yale Environment 360

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