The Horse 2020/21

Geothermal the new energy from the ground

Did you know we can use energy from the ground to heat our houses and buildings? 
The earth holds a lot of heat in its interior. With a combination of geothermal and heat pumps, it is now possible and it also saves energy. Because of the high potential, there are even new trials to produce electricity with earth's heat, but that needs a bit more time to be perfect. 

This new way of heating saves our environment and has many more good aspects. :)

What is geothermal?

Geothermal energy refers to the use of heat from the earth's interior. This energy stored in the earth can be used with the help of various methods. In most cases, geothermal probes are used in combination with heat pumps to heat single-family homes and large buildings. Geothermal probes go to depths of 200 to 400 meters. (personal pictures see below)

Electricity can also be generated from geothermal energy. However, in Switzerland, this requires drilling to depths of 2'000 to 5'000 meters in order to find the necessary temperatures of over 100 degrees. However, the technology is not yet as mature as when it is used for heating purposes. At the moment, no electricity is produced from geothermal sources in Switzerland. However, there are research and pilot projects, because the potential for generating electricity from geothermal energy is very large. Experts believe it is conceivable in the long term that a significant share of domestic electricity consumption could be covered by geothermal power plants. The advantages are obvious: geothermal energy is clean, seasonally independent, inexhaustible, and available on demand. In addition, the above-ground plants are inconspicuous, which can offer a decisive advantage compared to wind and hydropower.

Geothermal energy can be used to heat not only family homes but also large buildings or company premises. The potential is very large.

picture 1: Heat pump               picture 2: Generator

picture 3: Differenz temperature coming from the ground

picture 4: What heat is generated by compression

How does it work?

Liquid runs through pipes sunk into the earth and draws warmth from the constant temperature there. The heat is piped into an indoor unit and circulated through the house. During warmer months, the same system helps to cool the house. 

picture 5: How does it work

In the following video, you can find exactly how does geothermal works:

Explanation of the heat pump (youtube.com)

What is the problem?

When a house is heated with a geothermal probe, the probe extracts heat from the ground. The problem is that this heat only flows back very slowly. Most of the heat flows in from the side, which can lead to major problems in the long term, especially in areas with many borehole heat exchangers.

If there are no other installations within about 60 m of the borehole heat exchanger, this is not a major problem, as the temperature will settle at a certain level and the function of the installation will not be disturbed in the long term.

However, this looks quite different when several probes are built close together, as is increasingly the case in residential areas. Since in this case, no heat can flow in from the side, the ground cools down more, and moreover the years until the function of the system can no longer be guaranteed.

picture 2

Our opinion

We do not think that heating is too expensive and therefore a problem. However, the above-mentioned problem is important and needs to be addressed. We think it is good renewable energy and it can be revolutionary. Because more and more people switch to geothermal energy or build their houses with it. But it is not only private people who are convinced of this, but also many companies that care about the environment. We think that together with solar energy it is a step into the next technical generation.

Vocabulary

Quiz

1. What is the main problem with this heating source?
2. What are the advantages of this method?
3. 

You can find the correct answers in the comments.

Sources

- Save on energy (save on energy.com)
- archive (archive.epa.gov)
- How can we use the Earth's heat? (dontwastemy.energy)

Debora and Melane