You may be surprised to know, but geothermal energy has been being used by humans for hundreds of years. All those hot springs and roman baths you hear about. Well they were all powered by geothermal sources. Only now geothermal energy is heading to the average persons home.
In fact geothermal energy companies are already providing electricity in many countries. In the Phillipines, 25% of the country’s electricity comes from a geothermal source. In Iceland in 30%, El Salvador 25%. The United States only produces .3% of it’s electricity from a geothermal source although the first geothermal power station was built in 1960′s in California.
Geothermal energy is energy our planet naturally produces through sources such as compaction and pressure and the natural decay of radioactive isotopes. Areas where there are great pressure forces are found near tectonically unstable regions such as the coasts of many continents or along the rind of fire. These locations are usually the best places to harness geothermal power because of the higher heat gradient.
How does geothermal energy work?
So in order to harness energy from a geothermal source, we put a heat pump near a residence which circulates a high pressure refrigerant due to differences in heat between the surface and the interior of the Earth. In the summer months, the refrigerant absorbs the heat from the hot interior air and a fan circulates it back into the ground, while in the winter the refrigerant naturally brings up heat it absorbed from the Earth.
A geothermal system needs to be professionally installed and is not a diy project by any means. There are large loops of pipes which need to be installed underneath the house which will carry the coolant. An electrical motor will then either force the fluid into the earth, in the summer, or allow coolant to rise to heat the house, in the winter.
The whole process uses 25-50% less electricity than a conventional source and the Earth’s temperature gradient is stable and unchanging so it’s quite easy to estimate costs and the amount of potential energy a geothermal system could produce.