Now being readied 3.1 miles off the coast of Portugal, the first commercial wave farm will use the movement of the sea to generate 2.25 megawatts of electricity-enough to meet the
energy needs of more than 1,500 homes-from three 459-foot-long Pelamis Wave Energy Converters. Moored to the seafloor, each machine has four cylindrical pontoon-like segments. Passing waves will cause each machine to undulate like a giant sea snake. The motion tugs at the joints linking the segments, moving piston-like hydraulic rams inside the cylinders that pump pressurized oil through motors to drive electrical generators. If the first three converters are successful, the wave farm will eventually include 30 additional converters.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.