Renewable energy is energy that can be continuously be used and refilled drawing usually from natural regenerative sources or natural environmental processes such as wind, solar, and bio. It is often contrasted with non-renewable sources such as coal and fossil fuels which take longer to generate. Renewable energy uses energy flows that are replenished at the same rate as they are used.
About 13 percent of primary energy comes from renewables, with most of this coming from traditional biomass like wood-burning. Hydropower is the next largest source, providing 2-3%, and modern technologies like geothermal, wind, solar, and marine energy together produce less than 1% of total world energy demand but are expanding rapidly. The technical potential for their use is very large, exceeding all other readily available sources.
Current renewable energy technologies include:
- Solar Energy
- Non Solar Renewables
- OpenEI: Energy Data, Tools, Models, and other Resources
- Open-source Renewable Energy Project
- Overview of renewable energy wiki resources (Appropedia)
- USA: National Center for Appropriate Technology (NCAT) | National Renewable Energy Laboratory | U.S. DOE Energy Efficiency and Renewable Energy (EERE)
- International Energy Agency (2007). Renewables in global energy supply: An IEA facts sheet, OECD, p. 3.
- World Energy Assessment (2001). Renewable energy technologies, chapter 7.