Put simply, renewable energy is energy derived from a source that is not depleted when used. Sources can be replenished within the span of a human life. Sources of renewable energy include wind and solar power, geothermal, biomass and hydropower.

These types of energy sources, frequently called alternative energies, differ from traditional fossil fuels, such as coal, oil, and natural gas, which are considered non-renewable. Non-renewable energy sources are found in limited quantities in a limited number of countries, whereas renewable energy resources exist over wide geographical areas.

Renewable energy typically provides power in four areas: electricity generation, air and water heating/cooling, transportation, and rural energy services.

Solar energy is the cleanest, most abundant renewable energy source available. Solar technologies can harness this energy for a variety of uses, including generating electricity, providing light or a comfortable interior environment, and heating water for domestic, commercial, or industrial use.

Wind is moving air created as the sun heats the Earth’s surface. Windmills have been pumping water from the ground for hundreds of years. Today, Wind flow can be captured by wind turbines and converted into electricity.

Bio mass is the term for energy from plants. Bio mass uses plant matter and animal waste to create electricity. When converted properly, it is a low-carbon source of energy with little pollution.

Although hydropower was used hundreds of years ago to operate gristmills and sawmills, this renewable energy source is used today on a much larger scale to harness flowing water to move turbines which generate electricity.

Geothermal energy comes from the heat of the earth. This heat can be found close to the surface or from heated rock and reservoirs of hot water miles beneath the surface. Geothermal power plants can harness these heat sources to generate electricity for large areas, while a geothermal heat pump system can help heat or cool a single building.