Geothermal energy is characterized by heat coming from the Earth, it is heat energy generated less than 64 kilometers from the Earth's surface, in a layer of rocks, called magma, which reaches up to 6,000°C. Geo means earth and thermal corresponds to heat, therefore, geothermal is the heat energy that comes from the earth.
Magma results from tremendous pressures below the surface and heat generated by the decomposition of radioactive substances such as uranium and thorium. Finding fissures in the earth's crust, magma explodes in volcanic eruptions, or the released gases with their cooling, they heat groundwater that emerges in the form of geysers or water mines hot.
Electric energy can be obtained by drilling the ground in places where there is a large amount of steam and hot water, these must be drained to the earth's surface through pipes specific. The steam is then transported to a geothermal power station, which will rotate the blades of a turbine. Finally, the energy obtained by moving the blades (mechanical energy) is transformed into electrical energy through the generator.
The positive aspects of this type of energy are:
The emission of polluting gases (CO2 and SO2) is practically nil, not intensifying the greenhouse effect, unlike fossil fuels.
The area required for the installation of the plant is small.
It can supply isolated communities.
The negative aspects:
It is a very expensive and unprofitable energy, as it requires high structural investments and its efficiency is low.
It can cause the depletion of the geothermal field.
Lost heat increases the temperature of the environment.
The emission of hydrogen sulphide (H2S) occurs, which is extremely corrosive and harmful to health.
By Wagner de Cerqueira and Francisco
Graduated in Geography
Brazil School Team
Energy sources - geography - Brazil School
Source: Brazil School - https://brasilescola.uol.com.br/geografia/energia-geotermica-1.htm
