OCEAN ENERGY SWELL SLOWLY ROLLING IN

Salter’s Ducks were house-sized floating canisters designed by engineer Stephen Salter of the University of Edinburgh in the 1970s in response to the oil crises. Each was capable of generating 6 megawatts of wave energy-generated electricity. Initially expensive, Salter got the price down to competitive levels but the British government pulled funding.

Wave energy pioneer Salter testified in 1988 to the House of Lords it was the nuclear energy industry that stopped early development of ocean energy. New Energies could only develop when, Salter told the House of Lords, “…the control of renewable energy projects is completely removed from nuclear influences.”

Or, NewEnergyNews would add, when the costs of oil and new nuclear are so high people are finally willing to think anew about New Energy.

The intriguing story of Salter’s Ducks comes from an assessment of the present state of the wave energy industry by The Economist, the venerable and authoritative British weekly. The study examines why wave energy development has taken so long and concludes it is ready to emerge.

Nuclear industry conspiracies aside, one of the main reasons wave energy has been delayed in recent years, according to Economist sources, is that early experiments underestimated the ocean’s force, leading to trials of devices that could not endure the harsh oceanic environment. Another problem has been the lack of a durable transmission infrastructure to deliver the electricity generated at sea to the grid on shore.

Such challenges are now being met by engineering inventiveness. Tom Thorpe, consultant, Oxford Oceanics: “This is a completely new energy technology, whereas wind and photovoltaics have been around for a long time—so they have been developed, rather than invented…”

Anybody who has made a channel crossing can attest to the power there to be harvested. Britain’s centuries-old sea-conquering tradition and energy-rich island environs make harvesting ocean energy an obvious and potentially profitable choice. Thorpe, Oxford Oceanics: “If we couldn’t do it, who could?”

With energy prices skyrocketing, energy companies, utilities and venture capitalists are investing in development and testing. A spate of sturdy, newly designed devices are ready for deployment. Wave energy looks ready to take its rightful place alongside solar and wind energies as the truly renewable sources without a serious downside.

Salter's Ducks (click to enlarge)

The coming wave; Enthusiasm for renewable energy means wind turbines and solar panels are popping up all over the place. But what happened to wave power?
June 5, 2008 (The Economist)

WHO
Stephen Salter, pioneering wave energy engineer, University of Edinburgh; Pelamis Wave Power (Pelamis device), Finavera Renewables (Aquabuoy), AWS Ocean Energy (submerged buoys), Ocean Power Technologies (PowerBuoy), Aquamarine Power (Oyster), Wavegen (Limpet)

WHAT
Wave energy technology, newer than solar or wind but potentially a productive source of energy around the world, is beginning to emerge from a period of slow growth caused by growing pains.

click to enlarge

WHEN
- Wave energy devices were first patented in the 1700s.
- The first serious effort to capture wave energy on a large scale came from Stephen Salter, pioneering wave energy engineer at the University of Edinburgh, in the 1970s following the first oil crisis. Many, including Salter, think it was stymied by the nuclear industry.
- The world’s first commercial wave farm was launched in October 2007.
- In December 2007, California utility Pacific Gas & Electric (PG&E) signed a power purchase agreement (PPA) to buy wave-generated electricity beginning in 2012.
- No device has ever been deployed on a large scale.
- Finavera Renewables’ Aquabuoy developed a leak and failed a trial in 2007.

WHERE
- The first wave farm (Pelamis) is off Portugal. More to be installed off Orkney in Scotland and Cornwall in England.
- The PG&E PPA is for a wave installation (of Finavera Renewables’ Aquabuoy) off the central California coast.
- Ocean Power Technologies’ PowerBuoy is being tested off the coast of Spain.
- Testing of an Aquamarine Power prototype Oyster is set for this summer off the Orkney Islands.

WHY
- The “Wave Hub” – planned for installation off the coast of Cornwall in 2010 – is a prototype of the kind of seabed transmission infrastructure needed.
- Pelamis Wave Power (Pelamis device): Designed by a Salter stuident, it captures energy as waves move hinged joints on the 140-meter-long snake-like device. Each generates 750 kilowatts. Horizontal structure protects from severe seas. 3 are now deployed off Portugal and more are set for deployment in 2009.
- Finavera Renewables (Aquabuoy): 25-meter-long vertical tube floating on ocean surface and tethered to sea bottom, harvesting up-and-down motion, each device theoretically capable of 250 kilowatts.

The Wave Hub and some of the technologies to be tested there. (click to enlarge)

- AWS Ocean Energy (submerged buoys) and Ocean Power Technologies (PowerBuoy) are also bobbing buoy designs, the AWS one completely submerged.
- Aquamarine Power (Oyster): An oscillating 12-meter-tall and 18-meter-wide metal flap fixed near the shore that captures as much as 600-kilowatts of the wave’s energy as it rolls over.
- Wavegen (Limpet): Another shoreline device, three-chambered with a turbine atop. As waves roll in and out, they turn the turbine generating an average of 100 kilowatts and capable of being designed larger.

QUOTES
Tom Thorpe, consultant, Oxford Oceanics: “We have to be prepared for some spectacular failures…but equally some spectacular successes.”