A potential yet to be discovered

Techniques and infrastructure

Nowadays, in the midst of an energy transition that continues to advance at a rapid pace, renewable energy has now taken on a strategic value and an economic centrality that they had never known before. The levels of solar, wind, and hydroelectric energy production continue to stand out for their constant growth, especially in those nations or areas of the world that are applying to lead this historic phase of global energy transformation. In addition to traditional renewable sources, however, in recent years, another possible source of clean energy has begun to emerge in a discreet and powerful way. We are referring to geothermal energy or the possibility of valorizing the heat contained within the Earth for energy purposes. But what are the concrete ways to obtain the Earth’s heat and transform it into a source of renewable energy?

One of the most widely used methods is that of geothermal power plants, which draw heat from near the Earth’s surface to heat buildings or water. Typically, geothermal power plants drill wells about 1.5 miles deep so that the steam or hot water can be sent directly to the surface. The hot water is transferred to the surface by special mechanisms in high-pressure wells, which cause the water to turn into steam as it reaches the surface. The steam then powers a turbine, which is directly connected to an electricity generator. In the next stages, the steam is cooled and turned back into water, which is then pumped back into the Earth to begin a new valorization cycle. In most cases, these plants are located in specific locations, such as regions rich in hot springs and geysers and countries with intense volcanic activity, as they represent some of the few places on Earth where large quantities of heat are accessible close to the surface.

Geothermal pumps

However, geothermal plants are not the only method for valorizing the Earth’s heat. Thanks to geothermal pumps, in fact, the energy obtained from the heat can be used to heat homes and for numerous other practical purposes. The transfer of heat through these particular systems occurs by pumping water (or a special refrigerant) inside pipes located just below the Earth’s surface. In the winter months, the water or refrigerants are able to absorb heat from the Earth, then transfer it to homes or buildings located nearby (in the summer months, the operation follows the reverse path in order to cool the buildings). Again, once the heat transfer is complete, the water or refrigerant is pumped back into the depths of the Earth so that the process can begin again (just like in geothermal power plants).

The valorization of geothermal energy has certainly stood out over the years for its sustainable potential: by obtaining heat directly from the Earth, geothermal energy represents a solution with a low environmental impact and extremely low CO2 emissions. Since it is a resource available at any time, the Earth’s heat is also able to provide energy in a stable and constant way.