| Term | Definition |
| renewable resourse | energy sourcce, such as solar energy, that is replaced almost as quickly as it is used |
| photovoltaic cell | a divice that converts solar energy into electricty: also called a solar cell |
| hydroelectricity | electricity produced from the energy of moving water |
| geothermal energy | thermal energy contained in hot magma: can be converted by a power plant into electrical energy |
| biomass | renewable organtic matter from plants and animals, such as wood and animal manure, that can be burned to heat water and prodduce electricity |