Tidal Turbines: How They Work

Tidal turbines are much like underwater windmills, except the rotors are driven by consistent, fast-moving currents. The underwater rotors harness the power of the marine currents to drive the tidal generators, which in turn produce electricity. Since water is much denser than air, tidal turbine rotors can be much smaller than that of a wind turbine. Therefore, they can be put much closer together and still generate equivalent amounts of electricity. During operation, the average force of tidal flow is equivalent to 345 mph winds, generating 100 tons of thrust on the rotors.