Ocean power is one of the rare sources of energy that is reliable, predictable as well as dispatchable. Based on well understood principles of hydrodynamics and electrical engineering, ocean energy is an abundant, predictable and renewable resource.
The ocean power technologies have been in practice since hundreds of years. The tides and marine currents are calculated to be 832 times denser than the air flowing over wind turbines and are predictable up to the minute, at least 100 years in advance.
The tidal power of the oceans is tapped in two ways. The Dams are based on using a barrage at a bay or estuary with a large tidal range. In dams, power is generated primarily at ebb tides as the barrage creates a significant head of water. Tidal turbines take advantage of fast-flowing ocean currents to create energy. The most prolific tidal turbines are horizontal axis turbines that in many ways are analogous to wind turbines. He size is a difference. Tidal turbines generating 1 MW of power can be up to one-third the size of a wind turbine with a similar generating capacity. Ocean Turbine power can go a long way in powering the earth, as it is estimated that 0.2% of the ocean's untapped energy could power the entire world.