The word geothermal comes from a combination of Greek words geo (earth) and thermal (heat). Geothermal energy refers to the heat of the Earth’s core, which at the center reaches a temperature that is approximately equal to the surface temperature of the Sun. This heat can be used in the form of steam or hot water and is used for the heating of objects or products of electricity. The most practical for the exploitation of geothermal energy are areas where the hot mass is near the surface of our planet.
Geothermal energy is a renewable source of energy because heat is continuously produced within the Earth by various processes. In the first place is the natural disintegration of radioactive elements (primarily uranium, thorium, and potassium), which are found in all walls and produce enormous heat energy. In addition to radioactive decay, heat in the Earth’s crust is created in other ways: exothermic chemical reactions, crystallization of molten materials and friction in the movement of tectonic masses.
How deep do you need to go
When it comes to geothermal rock energy, today’s technology is limited to a drilling depth of up to 6 miles (10 km), and therefore exploitation to these depths is possible. If you go at greater depths, this energy is much higher. In the immediate future and until the time when technology is made that will enable the exploitation of this energy, hydro geothermal energy remains the only energy source. It has much less, but its technical usability is large, as is the economic justification of exploitation.
If calculated using up to a depth of 1.8 miles (3 km), reserves of hydro geothermal energy are about two thousand times more than coal reserves. The largest part of the energy carriers has temperatures below 212 Fahrenheit (about 88%), and only a small part has temperatures above 300 Fahrenheit (about 3%). It is estimated that stocks of geothermal energy far exceed the energy reserves of coal, oil, natural gas, and uranium together.
Benefits of using geothermal energy
- The use of geothermal energy does not contribute to the greenhouse effect,
- Geothermal power plants do not occupy much space and therefore have little impact on the environment,
- It’s a huge energy potential (it provides unlimited power supplies),
- The need for fuel has been eliminated,
- When the geothermal power plant is built, the energy is almost free, with less local consumption,
- The possibility of multi-purpose resource utilization (affects the economic justification of exploitation).
The disadvantages of using geothermal energy
- There are not many places where it is possible to build geothermal installations (conditioning by position, depth, temperature, a percentage of water in a particular geothermal reservoir),
- Restrictions on the composition of the walls and the possibility of access and exploitation,
- The heat source can be exhausted due to inadequate exploitation,
- The presence of hazardous gases and minerals is a problem in exploitation,
- Required high initial investment and high maintenance costs.