Water energy
Hydroelectric power plants continued to become larger throughout the 20th century. Hydropower was referred to as white coal for its power and plenty. Hoover Dam’s initial 1,345 MW power plant was the world’s largest hydroelectric power plant in 1936; it was eclipsed by the 6809 MW Grand Coulee Dam in 1942. The Itaipu Dam opened in 1984 in South America as the largest, producing 14,000 MW but was surpassed in 2008 by the Three Gorges Dam in China at 22,500 MW. Hydroelectricity would eventually supply some countries, including Norway, Democratic Republic of the Congo, Paraguay and Brazil, with over 85% of their electricity. The United States currently has over 2,000 hydroelectric power plants which supply 49% of its renewable electricity.
Wave and tidal power
The power of the rise and fall of the sea level or tidal power, can be harnessed to generate electricity.
Tidal Energy is literally powered by the universe. In other words, the gravitational forces of the moon and the rotation of the earth work together to create ebb and flood. The resulting differences in height create water flows that generate massive amounts of kinetic energy. Coastal lines funnel the flow of water this result in hydrokinetic energy (free waterflow). As long as the moon, the earth, the oceans and gravity exist, there will be tidal energy. Above all, it is universal and more reliable than other alternative sources of energy.
Tidal power traditionally involves erecting a dam across the opening to a tidal basin. The dam includes a sluice that is opened to allow the tide to flow into the basin; the sluice is then closed, and as the sea level drops, traditional hydropower technologies can be used to generate electricity from the elevated water in the basin. Some researchers are also trying to extract energy directly from tidal flow streams.
The energy potential of tidal basins is large but French engineers have noted that if the use of tidal power on a global level was brought to high enough levels, the Earth would slow its rotation by 24 hours every 2,000 years.
Tidal energy systems can have environmental impacts on tidal basins because of reduced tidal flow and silt buildup.
There are three basic ways to tap the ocean for its energy. We can use the ocean’s waves, we can use the ocean’s high and low tides, or we can use temperature differences in the water.
– Wave Energy
Kinetic energy (movement) exists in the moving waves of the ocean. That energy can be used to power a turbine.
Most wave-energy systems are small.
Hydropower equipment manufacturers
