Hydroelectricity

From PiqqoWiki

Hydroelectricity is the electrical power produced through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy.

Most hydroelectric power comes from the potential energy of dammed water driving a water turbine and generator. In this case the energy extracted from the water depends on the volume and on the difference in height between the source and the water's outflow. Hydroelectric plants with no reservoir capacity are called run-of-the-river plants. A less common type is the tidal power plant, which makes use of the daily rise and fall of water due to tides.

Since hydroelectric plants do not burn fossil fuels, they do not directly produce CO2. While some carbon dioxide is produced during manufacture and construction of the project, this is a tiny fraction of the operating emissions of equivalent fossil-fuel electricity generation. One of the reasons why run-of-the-river plants are more favourable than dams is that large reservoirs result in submersion of large areas upstream of the dams, destroying biologically rich and productive lowland and riverine valley forests, marshland and grasslands. The loss of land is often exacerbated by the fact that reservoirs cause habitat fragmentation of surrounding areas.

Brazil, Canada, Norway, Switzerland and Venezuela are the only countries in the world where the majority of the internal electric energy production is from hydroelectric power, while Paraguay not only produces 100% of its electricity from hydroelectric dams, but exports 90% of its production to Brazil and to the Argentine. Norway produces 98–99% of its electricity from hydroelectric sources.