Connect with us

Hi, what are you looking for?

CleanTechnica

Clean Power

Spain & Portugal Could Survive Just On Geothermal Energy

A version of this article was originally published on Sinc in Spanish.
By Luis Gonzalez

Mapa-de-flujo-de-calor-en-superficie-de-la-Peninsula-Iberica

Credit: UVA-WWW.LACASIG.COM

Spain could obtain all the energy the country needs just from the heat under the ground. No solar, no wind is needed. Nor from the old nuclear plants the Spanish government and the electric companies want to restart. There is the potential to produce up to 700 GW, but currently none is produced by this means.

The resource is geothermal power, a growing market that hasn’t reached the Iberian Peninsula yet, and is barely used in Europe. A new study from the University of Valladolid (UVa) published in the journal Renewable Energy with the title “An estimation of the enhanced geothermal systems potential for the Iberian Peninsula,” highlights the big capacity of Spain and Portugal to benefit from this natural resource.

The idea of geothermal energy is very simple; use the heat of the Earth to boil water, like any nuclear or thermal plant does, and use the steam to produce electricity. 24 hours a day, constantly. The heat is coming from the core of the planet, where the temperature is approximately the same as at the surface of the Sun (5,430°C). That is 6,371 kilometers under your feet, but in some areas of the so called Earth crust, the temperature might get up to 370°C due to portions of the mantle convecting upwards.

And there is the potential of the Iberian Peninsula, areas where the temperature reaches high values at shallow depths. According to the study, the areas of Galicia, western Castilla y León, the Sistema Central mountains, Andalusia, and Catalonia have the greater geothermal potential because at a depth of between 3,000 and 10,000 meters the temperature exceeds 150°C, and that is enough to get a geothermal plant to work.

The big number is 700 GW. Five times the current electrical power installed in Spain. This is obtained from calculations that consider wells with a depth between 3,000 and 10,000 meters and by means of enhanced geothermal systems (EGS). Although hard to get there, this depth is in the range of oil perforations. The number goes down to 190 GW for a maximum depth of 7,000 meters and 30 GW above 5,000 meters. To touch a sore spot, there are currently demonstrations in the Canary Islands (Spain) against offshore drilling for oil. The depth estimated for this perforation is 3,500 meters.

But there is something evil behind “enhanced” geothermal system. Enhanced means “to inject a fluid (water or carbon dioxide) under pressure” into a dry rock, creating fractures where the water is stored and heated up. Then, the hot water under pressure is extracted and cycled through a heat exchanger system (aka binary geothermal system) where electricity is produced. So, is this a kind of fracking?

Technically, it is, although it won’t be a legal problem in the case of Spain, since fracking is not forbidden there. In terms of water contamination and spills, it is believed that EGS uses a less aggressive technique based on degradable chemicals and lower pressure, and that the water reservoir is made, in principle, in a hot dry rock with no access to natural water resources.

In any case, more studies should be carried out to address this concern before annoying mother Earth, since another problem, also blamed on fracking, that has been reported from EGS is earthquakes. In 2009, Switzerland resolved to cancel an EGS plant in Basel after several studies stated that the enhanced seismic activity in the area was generated by the EGS power station. It must be said at this point that the plant in Basel was constructed on a known seismic fault.

The alternative to EGS is to exploit geothermal energy in a sustainable way, harnessing the heat that reaches the crust naturally. In that case, Iberia could profit from 3.2 GW of capacity. “It seems low, but it is the equivalent to three nuclear plants,” César Chamorro has declared, who is one of the authors of the study.

In a scenario where EGS could be put into practice without major risks, the main problem relies on the need of appropriated perforation techniques, a technical issue the oil companies are investing a lot of money and efforts to improve. They might be digging, literally, their own grave.

The authors have made use of the information collected in the Atlas of Geothermal Resources in Europe and surface thermal data available from NASA to publish this report and another paper in the journal Energy with the title “Enhanced geothermal systems in Europe: An estimation and comparison of the technical and sustainable potentials,” offering a similar study for Europe.

 
 
 
Appreciate CleanTechnica’s originality and cleantech news coverage? Consider becoming a CleanTechnica Member, Supporter, Technician, or Ambassador — or a patron on Patreon.
 

Don't want to miss a cleantech story? Sign up for daily news updates from CleanTechnica on email. Or follow us on Google News!
 

Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.
Advertisement
 
Written By

We publish a number of guest posts from experts in a large variety of fields. This is our contributor account for those special people, organizations, agencies, and companies.

Comments

You May Also Like

Aviation

Aviation is a big deal for climate change. Not only is it a big contributor, but it’s an area where changes to improve efficiency...

Clean Transport

The UK startup Tevva is on track to prove that batteries and fuel cells can coexist on one electric truck.

Climate Change

2022 effectively tied for Earth’s 5th warmest year since 1880, and the last 9 consecutive years have been the warmest 9 on record. NASA...

Climate Change

Greenland is home to the planet’s largest ice sheet outside of Antarctica. Observations collected from the ground, air, and space have revealed rapid thinning...

Copyright © 2023 CleanTechnica. The content produced by this site is for entertainment purposes only. Opinions and comments published on this site may not be sanctioned by and do not necessarily represent the views of CleanTechnica, its owners, sponsors, affiliates, or subsidiaries.