What is Tidal energy?
[[File:Moinho de água I.jpg|thumb|Tidal mill in Portugal]] '''Tidal energy''', sometimes called ''tidal power'', is using the energy of moving water in [[tide]]s and open ocean [[Ocean current|currents]]. It is most used for [[hydroelectricity]]. Tidal energy systems can take [[kinetic energy]] (energy caused by movement) from the moving water of rivers, tides and open ocean currents. They can also use [[potential energy]] from the difference in height between high and low tides. Getting energy from tidal currents is becoming more popular because people believe that it does not harm the environment as much as barrages or [[dam]]s. Many coastal sites around the world are being checked to see if they can be used to produce tidal energy. [[File:tide overview.svg|thumb|250px|Schematic of the lunar portion of Earth's tides (exaggerated)]] Like other [[hydroelectricity]] (electricity made using water), tidal power makes no [[pollution]] and is a [[renewable energy]] source. It is renewable because tides are caused by events that happen in the [[solar system]] and so will not run out. Tidal power has great potential for future [[Electric power|power]] and [[electricity generation]] because of the very large amount of energy contained in these systems. Tidal power is reliably predictable (unlike [[wind power]] and [[Solar energy|solar power]]). In [[Europe]], [[tide mill]]s have been used for nearly 1,000 years, mainly for [[Gristmill|grinding grains]]. Modern tide mills provide [[tidal stream power]]. Many things affect [[tide]]s. The pull of the [[Moon]] is the largest effect, and most of the energy comes from the slowing of the [[Earth]]'s spin. == Sources == * Baker, A. C. 1991, Tidal power, Peter Peregrinus Ltd., London. * Baker, G. C., Wilson E. M., Miller, H., Gibson, R. A. & Ball, M., 1980. 'The Annapolis tidal power pilot project', in Waterpower `79 Proceedings, ed. Anon, U.S. Government Printing Office, Washington, pp 550-559. * Hammons, T. J. 1993, 'Tidal power', Proceedings of the IEEE, [Online], v