Geothermal plant
Geothermal energy is that energy that can be obtained by taking advantage of the internal heat of the Earth. This heat is due to several factors, its own remaining heat, the geothermal gradient (increase in temperature with depth) and radiogenic heat (decay of radiogenic isotopes), among others.
The use of geothermal energy is widespread in some countries such as Iceland which accounts for almost 70% of the energy used due to its location. In other areas with the same possibilities, such as the Azores, it is not as widespread. In other countries like The Netherlands its use is limited to heating and in Madrid for example it is used in the internal air conditioning system of the metro. The application to agriculture, still not very widespread, could allow to have energy-sustainable greenhouses.
Geothermal energy is the most efficient energy both from the point of view of energy consumption and economic savings. Represents a energy savings and economical between 60 and 80% compared to traditional air conditioning systems such as gas or diesel oil. It is also more efficient than other renewable energies, such as biomass or solar, compared to which it represents savings of more than 50%.
Geothermal greenhouses
It is sought through the use of geothermal energy, not only to provide the plants with the best environmental and development conditions throughout their evolution stage, but also to reduce energy costs to the maximum and, more importantly, to reduce energy costs as much as possible. atmospheric pollution.
Greenhouses for agricultural use have energy needs that would require around 400 tons of fuel on average per hectare in the less warm months. These fossil fuel needs would be reduced to 0 by the use of internal heat and natural gas that is produced at certain depths.
By using different air conditioning techniques, a suitable temperature can be provided throughout the year by increasing the temperature in winter and reducing the interior temperature as necessary in summer. The use of geothermal resource in cascade is very frequent, since not all plants require the same caloric intake. In the first modules of the greenhouse, in contact with the hottest water, the plants with the highest need will be found. This cascade utilization saves costs and energy.
This type of energy has many advantages: energy dependence on the outside would be avoided, waste would be reduced to a minimum and would cause a lower environmental impact than those generated by combustion energy. In addition, this system is of great saving, both economic and energy, and supposes an almost total absence of external noise. It should also be borne in mind that it is renewable energy and not subject to market prices. The size required for a plant is very small compared to other energies and its visual impact is much lower since it does not require the construction of dams, logging of forests, or the construction of fuel storage tanks.
Although it also has some drawbacks: in some cases the emission of hydrogen sulfide that in large quantities is not perceived and is lethal, the contamination of nearby waters with substances such as arsenic, ammonia, thermal pollution, the deterioration of the landscape that cannot transport (as primary energy) and its use is limited to certain places.
Further information: Climate change: is the planet doomed to disaster?, Northern Europe on alert for strong storm, The most spectacular images of the eruption of the Grímsvötn volcano,