Geothermal energy can be installed anywhere

Geothermal energy: heating with geothermal energy

With the help of heat pumps, geothermal energy can be used for heating and hot water preparation. But how does it work, when does it make sense and what costs and effort can be expected?

Climate-friendly alternative to conventional heating systems

Geothermal energy is everywhere, in unlimited supply and an environmentally friendly source of energy - so it is no wonder that heat pumps with geothermal energy (= geothermal energy) are becoming increasingly popular as an alternative heating system.

Geothermal energy from a depth of up to 100 meters, i.e. near-surface geothermal energy, is usually sufficient to heat an entire house. To put it simply, a carrier medium pumps the geothermal heat from the inside of the earth into the house, in which an electric compressor feeds it into the heating circuit.

Geothermal energy is not the only type of heat for heat pumps. Our overview article shows you what else is available and what you need to know about heat pumps.

How is geothermal energy "tapped"?

But how does the geothermal energy get into the house from inside the earth? There are different ways of using the energy source and installing a heat pump with geothermal energy:

  • Geothermal probes: The probes are bored up to 100 meters deep into the ground. This makes them particularly effective because they work independently of the time of day and year and always achieve the same level of efficiency. For this variant, both a soil survey and many permits are required.
  • Geothermal collectors: The geothermal collectors, which are laid at a depth of around 1.2 to two meters below the surface, are significantly more cost-effective (as there are no high drilling costs). Since the temperatures at this depth fluctuate depending on the season, the collectors work more inefficiently than geothermal probes. Another major disadvantage is that the collectors take up a lot of space. The area must be about twice as large as the living space to be heated and only allow limited development and planting.
  • Geothermal baskets: This special design of geothermal collectors is installed up to four meters below the surface of the earth. As a rule, around three to four geothermal baskets are required to heat a single-family house. Since the baskets go down like a spiral, they take up a little less space than the usual collectors. Another advantage is that you can use and green the garden as normal.

Advantages and disadvantages of heat pumps with geothermal energy

From an energetic and ecological point of view, there is a lot to be said for purchasing a heat pump with geothermal energy. The geothermal heat pump - especially the one with geothermal probes - scores primarily with its high efficiency. It is not only a particularly environmentally friendly heating system, but also impresses with its low operating costs, which are mainly due to the electricity-driven compressor. Another advantage of the heat pumps is that they are extremely low-maintenance.

Despite all the advantages, the installation of a heat pump does not always make sense and, above all, it is not always possible:

  1. The environment must meet certain requirements: The geothermal collectors require a lot of space, but sufficient space must also be available for the boreholes for geothermal probes.
  2. In addition, it must be checked whether the soil quality is good enough for a heat pump.
  3. It should also be considered, depending on the region and climate, whether prolonged ground frost can affect efficiency.

Doesn't geothermal energy make sense for you? Solar thermal energy may be an interesting option. Read about what hybrid gas heating with solar can do.

Geothermal costs?

The costs for heat pumps with geothermal energy range from 15,000 to 25,000 euros. The decisive factor is how you make the heat usable. Heat pumps with collectors cost 15,000 to 18,000 euros; if you opt for geothermal energy using a geothermal probe, an investment budget of 20,000 to 25,000 euros can be expected.

What makes the geothermal probe more expensive? For the drilling alone you have to plan around 50 euros per meter of depth. With geothermal probes that reach 100 meters into the earth, this already adds up to 5,000 euros of the total costs.

The prices quoted are for guidance only, as factors such as the living space, the size of the system, the energy consumption and the condition of the house are included in the calculation.

However, due to the attractive funding programs of the Kreditanstalt für Wiederaufbau (KfW) and the Federal Ministry of Economics and Export Control (BAFA), the acquisition costs can be reduced significantly.

Who is geothermal energy suitable for?

Apart from the infrastructural requirements of the property, the conditions inside the house should also be right. In order for the heating system to work efficiently, the house must ideally not only have very good thermal insulation, but ideally also surface heating, as this requires a lower flow temperature than conventional convection radiators.

For these reasons, heat pumps are particularly suitable for new buildings in which the house and heating can be optimally coordinated. Existing buildings can only be used to a limited extent

Save heating costs even without a heat pump

Savings in heating costs are also possible without a heat pump. Just switching to a modern gas or oil condensing boiler means up to 30 percent lower heating costs. With Thermondo, this change is easy and convenient. Use our heating planner and, based on this, after a brand-neutral consultation, you will receive a non-binding offer that is perfectly tailored to your home.

Sebastian is the author of this article and our expert in the fields of heating systems and heat transition. If you have any questions about the article or about your heating change, write to him at :[email protected]