Sensible Sea Power

Here's the world's first tidal turbine power generator that just went into operation in Northern Ireland's Strangford Slough. The designer, Marine Current Turbines, says, "they can be installed in the sea at places with high tidal current velocities, or in places with fast enough continuous ocean currents, to take out copious quantities of energy from these huge volumes of flowing water."

The prototype, called "Seagen," is said to be powerful enough to provide the electricity needs of 1,000 homes. The twin rotors that can range from 15-20m in diameter, can be reverse pitched to function on both ebb and flood tides. The power units are attached to a wing-like structure that can be raised above sea level for maintenance.

Unlike windmills or solar generators, tidal energy is predictable and completely reliable. Tides ebb and flood every day, twice a day, without fail. Seagen is able to operate between 18-20 hours per day.