Tossing waves and restless seas. Motion on the ocean. Three-quarters of the world’s surface is covered with water that can’t stand still, and the people who live on the other one-quarter are engaged in a hunt for alternative energy sources.

Yet until very recently, there was a noticeable lack of commercial interest in trying to put those thundering waves and rolling swells to work. But the need to start generating electricity by means other than fossil fuels is reaching critical mass, so the concept of ocean waves as alternative energy producers is getting a closer look.

And in 2005, The Energy Policy Act opened the door for commercial interests to develop energy resources other than fossil fuels on the U.S. Outer Continental Shelf.

What alternative energy technologies may we see scattered among the oil rigs off the coasts of America in the not-too-distant future? Some possibilities:

Alternative energy oscillating water columns (terminators) stand perpendicular to the waves; water enters a underwater chamber and the motion of the waves forces the column of water to move up and down within the chamber. A pocket of air above the water is forced, like the air in a bellows, against a turbine which powers an electrical generator.

Attenuators, floating parallel to the waves like giant sea snakes, are segmented structures, with each segment the size of a box car. The unevenness of the waves causes them to flex at the joints, their movement forcing hydraulic oil to motors that drive alternative energy electrical generators.

“Overtopping” devices turn wave power into alternative energy with reservoirs filled above the level of the surrounding sea by incoming waves. When the water is released, gravity forces it back ocean’s surface; the energy released by the falling water turns hydro turbines.

And point absorber “farms” are arrays of buoys containing cylinders which move with the currents and drive electromechanical energy converters.

There’s alternative energy in them thar waves–and with the price of petroleum ever on the rise, the rush to commercially capitalize on it has only just begun.