Harvesting the Waves

This article elaborates ways of harnessing the power of the ocean. Engineers have attempted, with varying success, to tap ocean energy as it occurs in waves, tides, marine currents, thermal gradients, and differences in salinity. Among these forms, significant opportunities and benefits have been identified in the area of wave-energy extraction. As a form of harvestable energy, waves have advantages not simply over other forms of ocean power, but also over more conventional renewable energy sources, such as the wind and the sun. Wave energy also offers much higher energy densities, enabling devices to extract more power from a smaller volume at consequent lower costs. The Oregon State University (OSU) wave energy team is developing several novel direct-drive prototypes, including buoys that incorporate permanent magnet linear generators, permanent magnet rack-and-pinion generators, and contactless force transmission generators. The OSU researchers are also interested in small-scale wave-energy generators, which could be integrated into boat anchor systems to power a variety of small craft electronic devices.