Hello. Today, I'll be talking to you about Geothermal Energy and its applications in HVAC and DHW.
Geothermal Energy is the thermal energy generated and stored in the Earth. We can see here a classification of the different geothermal sources by temperature and application. We'll focus on very low temperature sources, since they are the only one that we can easily find in Spain.
Geothermal Power Plants are not very widespread, as there are not more than 10 GB installed worldwide. It is only widespread in Iceland, El Salvador, and the Philippines.
There are two different kinds of Geothermal Power Plants. Here, we can see that dry steam is used directly from the ground. However, when the ground cannot supply dry steam, a heat exchanger is required, as shown in the picture.
When we don't have neither a working fluid nor enough temperature, we have to work with brine and a geothermal heat pump to increase or decrease the temperature.
I'll explain briefly the different configurations exist in ground heat exchangers. The ground loops can be open or closed. The most common used in Spain is the closed one, since it is not easy to find underground water.
Furthermore, if we compared vertical and horizontal loops, we'd find that although the vertical one is much more expensive, it is nonetheless more commonly used, as the horizontal one has significant drawbacks / disadvantages.
You might be wondering if a geothermal heat pump can be used in any kind of building. I am happy to say that it can. I have different examples to demonstrate its versatility. A bank's new headquarters, a block of flats and a detached house.
These three projects are all in Madrid, by the way.