Geothermal power is power extracted from heat stored in the earth, and geothermal heating is basically direct use of the heat stored from the earth to heat our homes, offices, or for any other heating application. Geothermal heating is lately gaining in popularity and the estimated total installed thermal generation capacity is about 107,727 MW thermal.. This is still low number compared to traditional energy sources but nonetheless there are 88 countries which are currently utilizing geothermal energy for direct use applications.
In order to take a full advantage of geothermal power certain part of the world has to be underlain by relatively shallow geothermal resources. The best example of this is Iceland that is using full richness of its hot geothermal spots to harness energy. Currently there are five countries in the world (El Salvador, Kenya, the Philippines, Iceland, and Costa Rica) that generate more than 15% of their electricity from geothermal sources but I’ll focus in this article primarily on geothermal heating.
Many people do not know that direct geothermal heating has far better efficiency compared to geothermal electricity generation, mostly because it doesn’t require such demanding temperatures like geothermal electricity generation does. Now I will try to explain as simply as possible the principle on how does the geothermal heating work.
First what you need to know is that the most important part in this whole geothermal thing story are the geothermal pumps. Geothermal heating uses geothermal heat pumps to force the transfer of heat from the ground to the desired heating application. The usual geothermal heat pump has an outdoor unit called condenser and an indoor unit that’s called an evaporator coil. What we also need to transform heat from one source to another is refrigerant, that is usually in form of highly pressured liquid. As this highly pressured liquid circulates underground it absorbs heat from the ground and, on its return, the now warmer fluid passes through the heat pump which uses electricity to extract the heat from the fluid, and the re-chilled fluid is sent back through the ground to continue this cycle. This extracted heat is then used to heat our homes and offices.
It also has to be said that geothermal heat pumps are practically built on the same working principle like regular heat pumps, and the only big difference is that geothermal heat pumps extract heat from the earth instead from outdoor air like regular heat pumps do.
What are the main benefits of geothermal heating? The main benefit of geothermal heating is definitely energy conservation. If you cover current energy related media more closely you probably already know how energy conservation is one of the most important goals in modern energy and world’s attempts to go green. Energy conservation is definitely big advantage of geothermal heating systems because geothermal heating systems use between 25% to 50% less electricity than conventional heating or cooling systems. As you can see geothermal heating systems, where available, are one of the best options to go green.
Energy conservation is the main benefit of geothermal heating but is definitely not the only one. Geothermal heating has virtually no environmental impact, and is fully ecologically acceptable. Once installed, maintenance costs are very low not to mention how much more value do geothermal heating systems add to your property if you later decide to sell it. In humid conditions geothermal heating systems are excellent option because they maintain around 50% relative indoor humidity. They are ideal to use for under floor heating which is very popular these days. And also, they are very silent, not like some air conditioning devices that are often noisy.
As you can see there are many benefits in choosing geothermal heating, so if you get the opportunity to install it, make sure not to waste any time.