Geothermal energy is one of the most promising and powerful sources of energy. It is an endless source and can provide a great amount of energy. However, it is not a renowned technology. It can be used to provide cooling, heating and also to generate electricity. This last application has been analysed by an article. EGS (Enhanced Geothermal Systems) can produce electricity in an efficient and large scale for human consumption. Let’s see some of its characteristics.
Enhanced Geothermal Systems (EGS)
As you may know, geothermal energy is extracted from the ground. Depending on the depth reached, we can find normal temperatures (useful for cooling in summer), hydrothermal zones (suitable for heating in winter) or even some zones from which electricity can be generated. It must be beared in mind, that for each of those steps, we must go deeper. Normal temperatures can be found from surface to 100m deep. Hydrothermal zones from 100m to 4km deep. And zones for power generation between 4 and 5km deep.
The main problem of past methods to produce electricity from geothermal sources was that the resources were limited. Some studies show that after 30 years of exploitation, the resources could be finished. Therefore, a new method to generate electricity from the underground was required. EGS was the solution.
In the beginning, EGS was impossible to use. The necessary technology wasn’t available at that time. However, recent developments make it possible now. EGS can be explained as the process of extracting heat from “tight” rock that has not fractured naturally, where the permeability is generally low. Efforts are focussed mainly on exploiting heat from rock by using water as a working fluid: this water is pumped through areas of hot rock so that heat is exchanged.
EGS development and the study cases from Los Alamos Scientific Laboratory (USA) and Soultz-sous-Forêts (France) can be found in an amazing article published in Renewable and Sustainable Energy Reviews. We really encourage you to visit it and learn a bit more about geothermal energy and EGS.
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