5.089

Geothermal energy is the capturing of the Earth’s own heat. Geo means Earth, and thermal means heat. Since prehistoric times people have identified special places where the Earth’s heat comes up to the surface making hot springs and pools of water. Today, technological advances allow us to tap into the stored heat from the Earth to provide energy and heating for commercial and residential use.

The Earth’s core, 4,000 miles under the surface, has temperatures around 9,000 degrees Fahrenheit. In between this hot center and the Earth’s crust is the mantle. The top layers of the mantle are comprised of heated liquid rock called magma. This liquid rock is called lava when it erupts above the Earth’s surface as part of a volcano.

The ancient Romans used local hot springs for home heating as well as bathing. The first electric power plant to capture energy from the Earth was built in 1904 in Larderello, Italy.

Today there are three main types of geothermal power plants. Dry steam power reservoirs such as The Geysers plant outside of San Francisco, CA, use a process where steam from naturally occurring geysers is piped into a power plant. Operated by Calpine, the Geysers is the largest group of geothermal power plants in the world. The Geysers has been in operation since 1960 and produces 725 megawatts of electricity yearly. That’s enough to power San Francisco!

The two other methods of harnessing geothermal energy are a hot water reservoir or flash power plant and binary power plants. Flash power plants bring up hot water through deep production wells and then the steam separates and powers the plant’s turbines to create electricity. Binary power plants use water that is not hot enough for the flash power method but can still produce energy by being passed through a heat exchanger.
For commercial and residential use there is a another method available using geothermal heat pumps which capture stored solar heat from the ground for use in heating and cooling. These can be a sole source of heat and hot water, or can by used to supplement traditional fuel burning in places where they are not enough to produce all the heating needs of a building.

Geothermal energy is a renewable, economical, and relatively environmentally friendly. The use of geothermal energy will continue to grow, both for large power plants, and also smaller geothermal heat pumps. The downsides to geothermal energy are that there are only certain places in the world where the geothermal energy can be easily tapped and converted to energy in a large scale. There can be some environmental concerns related to the building of the large power plants used to capture the energy, including the impact of deep well drilling.

In those countries where volcanic natural resources are available, it makes sense to tap into this free heat for heating and electric production. Geothermal heat pumps can be used almost anywhere for primary and secondary production of heating and cooling. As countries offer tax incentives and fund research in alternative energy resources, we will be sure to see more and more geothermal energy creation.



Marianne Case
on behalf of the
BascoTec Internet Limited
Technologie Park 13
33100 Paderborn
Germany

Recommend or share this page: