Sustainable energy is energy that meets the needs of the present without compromising the needs of future generations. It is inexhaustible and has minimal negative impacts on human health and the healthy functioning of vital ecological systems, including the global environment. Sustainable energy sources include solar energy, wind energy, hydroelectricity, wave power, geothermal energy, tidal power and certain types of bioenergy (generally non-burning).
Conventional sources of electricity, such as coal, nuclear power, natural gas and oil provide cheap, reliable energy, but have a number of negative environmental, economic, and geopolitical side-effects. “Cheap energy” may end up being the most expensive energy ever used by mankind, since the price of this energy does not include the costs related to the pollution it creates. Carbon dioxide emissions from coal, oil, and gas-fired plants are one of the biggest contributors to climate change. Nuclear power is emissions-free, but currently presents the problems of nuclear waste disposal, plant failures resulting in dangerous radiation leaks, and issues surrounding feedstock (enriched uranium) security