Looking at turbines, the world's largest tidal turbine--a turbine powered by incoming and outgoing tides--is La Rance station, which produces some 240 MW and straddles a French estuary. Built in the 1960s, La Rance is likely to be the last of its type due to costs, size, and environmental problems. Instead, a second generation of individual freestanding turbines are being installed in Europe and the U.S. Marine Current Turbines Ltd., for example, placed a pilot 300-kW single rotor turbine in the Bristol Channel in southwest England and Wales in May 2003. Technical Director Peter Fraenkel says the company has developed a new generation of twin rotor units with the potential to generate up to 1 MW, depending on tidal flow.
by JEFF JOHNSON, C&EN WASHINGTON |
October 04, 2004