Types of Energy

Energy is the power we use for transportation, for heat and light in our homes and for the manufacture of all kinds of products. There are two sources of energy: renewable and nonrenewable energy.

Nonrenewable Sources of Energy

Most of the energy we use comes from fossil fuels, such as coal, natural gas and petroleum. Uranium is another nonrenewable source, but it is not a fossil fuel. Uranium is converted to a fuel and used in nuclear power plants. Once these natural resources are used up, they are gone forever.

The process of gathering these fuels can be harmful to the biomes from which they come. Fossil fuels are put through a process called combustion in order to produce energy. Combustion releases pollution, such as carbon monoxide and sulfur dioxide, which may contribute to acid rain and global warming.

Renewable Sources of Energy

Renewable sources of energy can be used over and over again. Renewable resources include solar energy, wind, geothermal energy, biomass and hydropower. They generate much less pollution, both in gathering and production, than nonrenewable sources.

  • Solar energy comes from the sun. Some people use solar panels on their homes to convert sunlight into electricity.
  • Wind turbines, which look like giant windmills, generate electricity.
  • Geothermal energy comes from the Earth's crust. Engineers extract steam or very hot water from the Earth's crust and use the steam to generate electricity.
  • Biomass includes natural products such as wood, manure and corn. These materials are burned and used for heat.
  • Dams and rivers generate hydropower. When water flows through a dam it activates a turbine, which runs an electric generator.

Energy and the EarthEnergyGreatest Oil Reserves by Country, 2006