What is Renewable Energy?

Our country currently relies heavily on fossil fuels, such as coal, oil, and natural gas for its energy. These fossil fuels are nonrenewable, that is, they will eventually run out, becoming too expensive or too environmentally damaging to develop. Contrastingly, renewable energy resources—like the wind and solar energy—are constantly replenished and will never run out.

The majority of renewable energy technologies are directly or indirectly powered by the sun. Our planet is in equilibrium such that heat radiation into space is equal to incoming solar radiation, the resulting level of energy can roughly be described as the Earth's climate. The oceans absorb a major fraction of the incoming radiation. Most radiation is absorbed at low latitudes around the equator, but this energy is dissipated around the globe in the form of winds and ocean currents. Wave motion may play a role in the process of transferring mechanical energy between the atmosphere and the ocean through wind stress. Solar energy is also responsible for the distribution of precipitation which is tapped by hydroelectric projects, and for the growth of plants used to create biofuels.

There are almost infinite amounts of renewable energy sources for our planet to harvest for our needs. An example of the vast amounts of energy from renewable sources versus our global demand for energy is explored in the chart below: 

The volume of the cubes in the chart above represent the amount of available geothermal, wind and solar energy in terawatts (TW) or one million watts. The red cube on the right represents the proportional total global energy consumption.

Types of Renewable Energy

There are many different types of renewable energies.  The most popular being solar power, wind power, biofuels and biomass, water power, hydrogen, geothermal, wave power, and tidal power. For more information on other types of renewable energy, please visit the following:

Biofuels and Biomass

The organic matter that makes up plants is known as biomass. Biomass can be used to produce electricity, transportation fuels, or chemicals. The use of biomass for any of these purposes is called biomass energy.

Geothermal Energy

Geothermal energy taps the Earth's internal heat for a variety of uses, including electric power production, and the heating and cooling of buildings.

Hydrogen Power

Hydrogen is always combined with other elements, like with oxygen to make water. Once separated from another element, hydrogen can be burned as a fuel or converted into electricity.

Water Power or Hydropower

Flowing water creates energy that can be captured and turned into electricity. This is called hydroelectric power or hydropower.

Solar Power

The bulk of all renewable energy comes either directly or indirectly from the sun.

Tidal Power and Wave Power

The ocean produces energy from the sun's heat and mechanical energy from the tides and waves.