Hydroelectric
Hydro power systems convert potential energy stored in water held at height to kinetic energy (or the energy used in movement) to turn a turbine to produce electricity. Energy available in a body of water depends on the water?s flow rate and the height (or head) that the water falls. The scheme?s actual output will depend on how efficiently it converts the power of the water into electrical power (maximum efficiencies of over 90% are possible but for small systems 60?80% is more realistic). Hydroelectric developments offer a clean source of electrical energy with a steady output and no production of particulates or harmful gases. A scheme with a capacity of 100kW would typically supply enough electricity for about 150 homes. This is equivalent to emissions from fossil fuel power stations of around 400 tons per year of carbon dioxide, as well as around 5 tons of sulphur dioxide and 2 tons of nitrogen oxides.