Oh Buoy, How Revolting

Green power is supposed to use stuff in nature that is already generating energy, harness it in some way, and then convert that process into electricity to be added to the power grid. The idea is not to destroy the environment but to use what is already there effectively without pollution. Wind power has been reduced to a spinning turbine based on one form of blade or another capturing air flow. Hydroelectric power seemed like a good idea – and it is particularly useful when transporting water up and down hills – but dams introduced a whole new spate of issues with silting, population displacement, interference with natural migration patterns (like salmon spawning upstream) and more than one huge accident or two. Geothermal produces earthquakes, and solar is getting there, but the panels are still pretty expensive, and storing electricity in existing battery technology consumes rare earths and creates environmental disposal issues that still plague designers.

Oceans? Rising currents and waves? Hey, how ‘bout dem possibilities? Well, after over three decades of experiments and research with modern technologies (in 1799, someone proposed using wave power to drive mechanical and industrial machines much like using a flowing river to spin a mill wheel), we still haven’t settled on the best solution. But we’re trying.

Wave power is on the cusp of commercial deployment, so it might be interesting to understand the process. “The energy in waves comes from the movement of the ocean and the changing heights and speed of the swells. Kinetic energy, the energy of motion, in waves is tremendous. An average 4-foot, 10-second wave striking a coast puts out more than 35,000 horsepower per mile of coast… Waves get their energy from the wind [impacted by tidal gravitational movement and the rotation of the earth]. Wind comes from solar energy. Waves gather, store, and transmit this energy thousands of miles with little loss. As long as the sun shines, wave energy will never be depleted. It varies in intensity, but it is available twenty-four hours a day, 365 days a year... Ocean wave energy technologies rely on the up-and-down motion of waves to generate electricity.” OceanEnergyCouncil.com.

While different companies and research institutes have designed different generators to harness wave energy – none of the solutions is cheap; they have to withstand harsh weather and corrosive saltwater yet be large enough to make a difference – there really are three basic approaches to garnering electricity from oceanic waves: “[1] Float or buoy systems that use the rise and fall of ocean swells to drive hydraulic pumps. The object can be mounted to a floating raft or to a device fixed on the ocean floor. A series of anchored buoys rise and fall with the wave. The movement ‘strokes’ an electrical generator and makes electricity that is then shipped ashore by underwater power cable

“[2] Oscillating water column devices in which the in-and-out motion of waves at the shore enter a column and force air to turn a turbine. The column fills with water as the wave rises and empties as it descends. In the process, air inside the column is compressed and heats up, creating energy the way a piston does. That energy is then harnessed and sent to shore by electrical cable.

“[3] ‘Tapered channel’ or ‘tapchan’ systems, rely on a shore-mounted structure to channel and concentrate the waves, driving them into an elevated reservoir. Water flow out of this reservoir is used to generate electricity, using standard hydropower technologies.” OceanEnergyCouncil.com

The Oregon coast will be host for the first federally-licensed oceanic wave power generation system, based on the buoy technology. “[T]he first commercially licensed grid-connected wave-energy device in the nation, designed by a New Jersey company, Ocean Power Technologies, is in its final weeks of testing before a planned launch in October. The federal permit for up to 10 generators came [in August], enough, the company says, to power about 1,000 homes. When engineers are satisfied that everything is ready, a barge will carry the 260-ton pioneer to its anchoring spot about two and a half miles offshore near the city of Reedsport, on the central coast.

“‘All eyes are on the O.P.T. buoy,’ said Jason Busch, the executive director of the Oregon Wave Energy Trust, a nonprofit state-financed group that has spent $10 million in the last six years on scientific wave-energy research and grants, including more than $430,000 to Ocean Power Technologies alone. Making lots of electricity on the buoy and getting it to shore to turn on lights would be great, Mr. Busch said. Riding out the storm-tossed seas through winter? Priceless. ‘It has to survive,’ he said… Adding to the breath-holding nature of the moment, energy experts and state officials said, is that Oregon is also in the final stages of a long-term coastal mapping and planning project that is aiming to produce, by late this year or early next, a blueprint for where wave energy could be encouraged or discouraged based on potential conflicts with fishing, crabbing and other marine uses.” New York Times, September 3^rd. Let’s hope!

I’m Peter Dekom, and we need the energy and the potential jobs that come with a successful system based on an American design.