Electricity from the sea

“It is pleasant, on a choppy but sunny day, to sit beside the gray, concrete structure and listen to the rising and falling of the waves, driving air through the turbines like the breath of a great sea monster,” science teacher Roy Husthwaite said. “It seems insane to me to be investing in nuclear power stations and gas turbines when there are endless, free energy resources in the rivers, oceans and the wind.”

In a world addicted to fossil fuel, turning waves into watts might seem far-fetched. But as the U.S. and other countries look for alternatives to oil, natural gas and coal and try to curb global warming, ocean power gradually is joining the ranks of wind and solar power as a source of renewable energy.
Anyone who has ever been slammed to the sand by a wave can attest that the ocean packs tremendous power. Technology can harness that energy in several ways. Some designs, like the Limpet, use waves to push air through a column. Others convert the sea’s up-and-down motion into mechanical energy.

While U.S. regulators categorize wave power as hydropower, it differs from other methods of generating energy from water. Tidal power, for instance, relies on the gravitational force of the sun and the moon to provide energy. Wave power is less predictable than tidal power, but experts consider it more potent.

Los Angeles Times