Is geothermal energy more expensive than solar or wind energy?

Answer

Dear Francois,

The short answer is yes, and that the cost price and thus the profitability of geothermal energy varies greatly according to local conditions and is therefore highly variable. In Iceland, so to speak, you have to make a well of 5 m to have boiling water with which you can even run a turbine to produce electricity. With us you have to dig a well of 1 km deep to find enough hot water and per meter in depth the investment costs for the installation are high and the concept is difficult to achieve. The research institute VITO conducts research into geothermal energy and this will show how feasible this is. All kinds of difficulties can arise. For example, I know that the former flooded coal mines in Genk contain warm water, but it is very salty water and also polluted with all kinds of substances that are present there and that make it very difficult to make an exploitation feasible.

On the other hand, it is indeed an “inexhaustible” source of energy by human standards, but you have to be able to get it and certainly as a general energy source the temperature must be sufficiently high. Another option, especially for domestic heating needs, which is moving forward and which is more feasible in our regions, is the combination of geothermal heat and a heat pump. This is also an expensive investment and where the discussion about the electricity bill that accompanies it has not yet settled. Personally, I think we should think about a central investment for a neighborhood in which hot water can then be distributed via heat networks and that the available energy is upgraded per location with a heat pump for heating in the home.

Well, as a tentative conclusion then, I don’t think there is a clear-cut view available at the moment and that this is still the subject of studies. Undoubtedly, as the concept develops technologically, heating systems linked to geothermal energy will become feasible and may fill a specific part of our energy needs. I hope this answer somewhat answers the question.

Regards,