Power from the Powerful Oceans

February 26, 2007 – Vol.11 No.49

POWER FROM THE POWERFUL OCEANS.

The challenges are daunting, the rewards profound. Imagine trying to develop a device that can withstand the force of storm-driven waves, be durable enough to resist the corrosive effects of salt water, do no harm to marine life, yet be able to generate electricity at rates consumers can afford.

If engineers and scientists can meet those challenges the reward would be endless, reliable, consistent and emission-free power for the whole planet: power from waves, ocean and tidal currents.

At this stage in development ocean power technology is about where wind energy was in the early 1980’s: Many ideas on how to generate power, but no predominant technology yet.

But that may soon change. Scotland, with its excellent wave and tidal current resources, is about to inject another resource into ocean energy: cash.

Scottish Development International, a business/knowledge development arm of the Scottish Executive, has announced grants of more than $25 million (GBP 12.75 million) to be distributed to nine pioneering ocean power technology companies. As winners of the bidding process, the companies will deploy prototypes for testing and evaluation at the European Marine Energy Centre (EMEC) in Orkney. The prototypes, expected to be in the water this year, will be commissioned in 2008 providing power to the local grid. EMEC is an ocean energy research facility.

This is the real deal. The machines will have to prove themselves. There’s a wide variety of technologies that will be deployed singly or in arrays:

AWS Ocean Energy, receiving $4.15 million (GBP 2.128 million), will install a beneath-the-waves, wave energy converter to the ocean floor. It works by harnessing the differential in pressure as waves pass overhead: high pressure at the wave crest, low at the trough. It converts air pressure inside the converter to electricity by way of a floater piston and linear generator.

ScotRenewables, $3.5 million (GBP 1.8 million) received, will deploy its ScotRenewables tidal turbine (SRTT). It’s a cylindrical buoyancy tube with arms attached to subsurface nacelles. Rotors on the nacelles turn in currents and generate electricity. The rotor nacelles can be retracted when the device needs to be moved.

Open Hydro, $2.36 million (GBP 1.214 million), has already installed its sea-bottom, shaftless underwater tidal turbine at the site. The turbine turns as tidal currents pass, but the turbine’s open center allows fish to pass though.

Ocean Power Technology (OPT), $1.16 million (GBP 598 million), will install its PowerBuoy, which moves up and down on a central spar as wave pass to generate electricity. (OPT has also announced that it has signed a cooperative development agreement with the Pacific Northwest Generating Cooperative (PNGC) for the Reedsport OPT Wave Park planned for waters near Reedsport, Oregon, in the US.)

Aquamarine Power, $536,000 (GBP 275,000) will install its Oyster device which catches the power of waves as they move towards shore.

Wavegen, $290,000 (GBP 149,000), will install an advanced turbine at its existing Limpet Oscillating Water Column (OWC) wave energy generator. Limpet, which has been in operation for a number of years, uses air compressed by waves to drive a turbine generator.

Tidal Generation, $150,000 (GBP 77,000), will test one of its bottom mounted, propeller-like tidal turbines at a special testing area at EMEC.

CRE Energy, $8.07 million (GBP 4.141 million), will install four Ocean Power Delivery Pelamis devices as a single wave energy array for 3 megawatts of power. The Pelamis devices are already being tested off Portugal, but the more powerful EMEC installation will become the largest ocean wave power facility in the world.

CleanTechCom, $532,000 (GBP 273,000), will install two, 1-meter siphon pipes near the EMEC facility for an undescribed power generation scheme.

The European Marine Energy Centre itself will get additional funding for upgrades related to the installations.

Visit the EMEC http://www.emec.org.uk/
AWS Ocean Energy at http://www.awsocean.com/
ScotRenewables at http://www.scotrenewables.com/
Open Hydro at http://www.openhydro.com/
Ocean Power Technology at http://www.oceanpowertechnologies.com/
Aquamarine Power at http://www.aquamarinepower.com/
Wavegen at http://www.wavegen.com/
Tidal Generation at http://www.tidalgeneration.co.uk/
Ocean Power Delivery at http://www.oceanpd.com/
Scottish Development International at http://www.scottishdevelopmentinternational.com/