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.