The Pelamis Wave Energy Converter is a new technology that uses the motion of ocean surface waves to create electricity. The device has been successfully tested at the European Marine Energy Centre (Emec).
It is an elongated metal unit that looks like a big semi-submerged sausage, with hinged segments that rock with the sea, up and down and side to side, pumping fluid to hydraulic motors that drive generators. The power produced by the generators is fed into underwater cables and brought to land where it enters the power grid.
The large, tubular segments were taken to a site off the northern coast of Portugal last year for a project which aimed to generate enough power for 1,500 households. This is possible thanks to the 2,700 MegaWatt that each unit can generate in one year (source). Now Scottish Power is planning a venture which it believes could create enough power for 2,000 homes.
The Pelamis is designed for survivability rather than highly efficient energy conversion. This means that rather than absorbing all of the energy available in a wave, it converts only a portion of that energy to electricity. This is principally so that the device can survive in dangerous storm conditions which could do considerable damage to a wave device attempting to absorb all the available energy.
