For thousands of years, geothermal energy has been used in some countries for cooking and heating. This kind of energy is derived from the internal heat of the earth. It is contained in the rock and fluids located beneath the crust of the earth. This form of energy is found in shallow ground to a couple of miles below the surface and can even go further to the magma which is a very hot molten rock.
Geothermal energy is generated in more than 20 countries, with the United States being the largest producer in the world. A lot of the buildings and swimming pools in Iceland are also heated using geothermal hot water (the country does have at least 25 active volcanoes as well as several hot springs and geysers). But despite the many advantages of geothermal energy, there are also certain disadvantages. Here’s a look at what they are:
List of Pros of Geothermal Energy
1. It can be extracted without burning fossil fuel.
Coal, gas or oil are examples of fossil fuels and harvesting geothermal energy doesn’t require the burning of any of those fuel types. Moreover, this kind of energy is renewable as it comes from natural resources and as such, can be replenished.
2. It is friendly to the environment.
According to National Geographic, “Geothermal fields produce only about one-sixth of the carbon dioxide that a relatively clean natural-gas-fueled power plant produces.” Also, binary plants don’t release emissions.
3. It is always available.
Alternative energy sources such as solar and wind energy rely on the weather. However, geothermal energy is always available each day of the year.
4. It is not that expensive.
The savings from the direct use of geothermal energy can be as huge as 80% compared to fossil fuels.
List of Cons of Geothermal Energy
1. It has some environmental issues.
While harnessing geothermal energy is deemed relatively safe, there are some concerns regarding its emission of hydrogen sulfide which is a gas that smells – at low concentrations – like rotten egg. Another cause for concern is the disposal of geothermal fluids which contains low levels of toxic materials. However, supporters believe that the level of pollution associated with this kind of energy is a lot less compared to the impact of coal and other fossil fuels.
2. Geothermal sites may cool down.
It is true that geothermal sites can produce heat for many, many years. However, specific locations may eventually cool down. Also, although geothermal energy is available all year round, it is not available everywhere. Countries like Iceland are blessed with great resources and can generate close to one third of their electricity using geothermal energy.
3. It can cause surface instability.
Geothermal power plants need to be constructed and the building of these structures often affect the stability of land. Plants like these have also been linked to subsidence (this is the motion of the surface of the earth) in Germany and New Zealand. Also, an earthquake can be triggered because of hydraulic fracturing (or fracking) which is an important part of developing enhanced geothermal system power plants.