Tidal energy, or tidal power, is a little known and little used energy source. Yet it is a very old energy source, dating back to the middle ages in Europe. Tidal energy is created by the relative motion of the Earth, Moon, Sun, and the gravitational interactions between them. Every coastal region has two high and two low tides in each approximate 24 hour period. A big advantage of tidal energy is its predictability. The size and time of tides can be predicted very efficiently.

Tidal energy is little used around the world. In order for electricity to be generated, differences between high and low tides must consistently reach 16 feet. There are few regions in the world where this occurs. There are currently no tidal energy facilities in the United States although there is potential in the Pacific Northwest and the Atlantic Northeast.!!!!!!

Here's a comprehensive tidal energy definition. Hope it helps.

http://www.renewables-info.com/energy_de...

It is the power of the rise and fall of the sea level.

energy u get from the oceans.