Geothermal energy: Using technology to harness free electricity from within the Earth

Geothermal energy is heat that is stored inside the Earth’s crust where radiogenic elements like uranium, thorium and potassium are decaying and producing heat. Although underground heat can be found anywhere inside the Earth, wherein if you keep on drilling you will eventually hit the Earth’s crust, geothermal plants are best located in areas with volcanic activity, hot springs and geysers as viable and efficient levels of electricity can only be generated in certain spots.

Geothermal energy: is it really better than nuclear power?

In a nutshell, geothermal energy is allegedly as good as nuclear energy minus the risks. In order to illustrate this clearly, let us look at the pros and cons of geothermal energy.

Advantages of geothermal energy

1. Reliable source of energy
This is perhaps the biggest advantage of geothermal energy as compared to other renewable sources. Unlike wind, water and sunlight, geothermal can achieve higher loads and can produce a consistent supply of energy.

2. Renewable and sustainable energy source
Like other renewable and sustainable sources such as water, wind and sunlight, geothermal energy does not rely on the burning of fossil fuels to generate energy. Since it does not deplete the earth’s natural resources, it helps to preserve an ecological balance. Geothermal energy will never run out. It is a constant energy source that is naturally replenished.

3. Clean source of eco-friendly energy
The process of harnessing heat from geothermal energy is by drilling holes into the earth so that the heat trapped within is expelled. During this process some greenhouse gases may be released, but these levels are significantly lower, in fact, only a very small fraction as compared to the amount of toxic gases that fossil fuels produce.

Whatever greenhouse gas is released, it is so small that it can be easily contained and neutralized. Since no fossil fuels are burned in the process of generating energy no harmful emissions are released into the atmosphere. Because it virtually produces very little to no greenhouse gases, geothermal energy does not contribute to global warming.

Reduces the risk of oil spills from transporting oil.

4.Efficient way to lower down and stabilize energy costs
Geothermal energy will always be free. The cost of energy is stable (and cheaper) as geothermal energy is not dependent on the market’s supply and demand of oil. You need not worry about oil price fluctuations.

Once a geothermal site is established and the plant is running, the cost and efforts to operate it is very small especially if you compare it to the cost and effort of running a traditional power plant that relies on oil or coal. Geothermal power plants are self-sustaining. Operating a geothermal power plant only requires power to be supplied to the mechanical components and this power comes from the plant itself. Geothermal plants require a smaller land space as compared to traditional power plants.

5. Geothermal energy benefits the economy
Generates jobs for the community. Tax revenue generated is used to benefit the local community. Reduces a region or even a country’s dependency on oil-exporting countries and the erratic world oil market. Generates domestic geothermal royalties.

With the above-mentioned factors, it is clear that geothermal energy provides a plethora of benefits on a global level. But if it is that good, why isn’t it used more? If it can supply a constant flow of electricity round-the-clock, clearly an attribute that wind and solar power do not posses, why is geothermal energy left behind with only 3-4% growth?

Disadvantages of geothermal energy

1. Location
Although we will be able to find hot rocks anywhere beneath the earth, we need to get to these rocks at a depth that allows for easy drilling. The ground above the hot rocks need to be soft enough to drill through and the hot rocks must not be located too deep within the earth. For this reason, geothermal power plants are only located in areas where there are hot springs, geysers or volcanic activity.

2. Time it takes to set up a geothermal power plant
Wind and solar energy is so easy to set up that it is used not only in energy farms but also in homes. Installation can take a maximum of six months for a small wind farm, three months for a solar energy plant and mere weeks or even days to install renewable energy sources in homes. In the case of Geothermal Power plants, since the planning and developing process along with the construction is more complex, it can take years!

3. Technological impediment
Indeed geothermal energy has the capacity to supply hundreds of thousands of watts of electrical power through new techniques such as Enhanced Geothermal System, but the disadvantage of geothermal energy technology is its availability. Additionally, the rate of improvements on this technology is slow.

4. Financing
There are few geothermal developers that can fund projects. Some of which are Chevron and Calpine; however, these are big developers and finding small project developers is a difficult task.

5. Regulations and Permits
One of the disadvantages of geothermal energy power plants that makes it so different from its simpler renewable energy source counterparts, is the complexity involved in its development. Because of this, there are lots of paper works involved in the planning and developing of a geothermal plant.

6. Geothermal activities sometimes temporarily ceases
Although we did say that geothermal energy is the most consistent and it is indeed renewable, there are occasions when geothermal activity would just stop for a few months before it decides to start producing heat again. This poses a very big loss not only for the community it supplies energy to but to the developers who financed the creation of the plant, because once it runs out of steam, there is nothing that can be done but wait for it to start producing heat again. Since investment in a geothermal plant is big, many developers do not want to take this risk.

7. Exclusiveness
Energy cannot be transported and it can only provide energy to areas close to it.

8. Tectonic activity
Since geothermal power plants are best located near tectonic plates, there is the risk of earthquakes and volcanic activity. This is perhaps the biggest among the disadvantages of geothermal energy; as it can not only damage the plant but also endanger the surrounding community.

The advantages and disadvantages of geothermal energy pose a dilemma. Some countries like Japan, Philippines and Iceland and US states like California and Hawaii benefit from this renewable energy source. But not everyone can, especially as its needs, in terms of location, are very specific. Also, the gestation costs and financial risks involved in investing in geothermal energy are very serious factors that it has hindered the popularity of geothermal energy as an electricity generator.