Current Geothermal Energy Pros and Cons

Geothermal Energy / Development Technology

 James Bratley reports that geothermal resources can be harnessed in order to generate electricity. With this process comes a number of advantages and disadvantages. In this article, we will take a look at these different geothermal energy pros and cons.

The Pros

1. Renewable and Sustainable
Geothermal energy is both renewable and sustainable. This means that it will never run out, unlike non-renewable energy sources. For as long as the earth supports life, geothermal energy will exist. Because of this, geothermal power has the edge over non-renewable alternatives.

2. Environmentally Friendly
Geothermal energy is an environmentally friendly energy source. When used to generate power, it has a much lower impact on the environment than using fossil fuels.

3. Constant Supply
Unlike other renewable energy sources, geothermal energy can provide a constant power supply. Solar panels can only produce electricity during the day. Similarly, wind turbines only produce power when there is enough wind. The advantage of a constant electricity supply makes Geothermal energy far more predictable than its rivals.

4. Small Footprint
Geothermal power plants have a smaller footprint than their coal, oil, and gas equivalents. Although they will reach far down beneath the earth’s surface, their land footprint will be small. This factor also helps to conserve land space and reduce visual pollution. 

5. Cost-Effective
We can use geothermal energy to provide a source of cost-effective electricity. Power generated from geothermal energy is one of the cheapest electricity sources available today.

6. Low Maintenance
Geothermal installations are low maintenance when compared to traditional power plants. As a result of this, they are reliable and cheap to run.

7. Low Noise
Generating power from geothermal energy produces little noise. The main source of noise comes from fans contained in cooling systems. To mitigate this, engineers can install dampening materials in generator houses. This helps to reduce noise pollution.

8. Reduces Fossil Fuel Dependency
When we use geothermal energy, we cut our dependency on fossil fuel alternatives. This is not only great for the environment. It also means we are less vulnerable to supply and demand issues associated with fossil fuels.

9. Increases Energy Security
Geothermal energy can help to increase energy security. By using local geothermal resources, we reduce the need to source supplies from other countries. As a result of this, we are less reliant on external influences. This in turn helps to increase our energy security.

10. Job Creation
The creation of a global geothermal energy industry has helped to create jobs all over the world. The geothermal industry supported 35,000 American jobs between 2012-2013. This is according to a 2014 report from the International Renewable Energy Agency (IRENA.)

11. Huge Potential
Geothermal power has huge potential in some parts of the world. A recent study by the Geothermal Energy Association (GEA) estimates that just 6.5% of this potential has been tapped so far. In fact, global geothermal energy potential could be in the range of 35 gigawatts (GW) to 2 terawatts (TW.) This figure has been estimated by the Intergovernmental Panel on Climate Change (IPCC).

The Cons

1. Geographical Limitations
Geothermal energy is arguably the most location-specific energy source known to man. Geothermal activity is at its greatest along tectonic fault lines within the earth’s crust. It is at these locations where geothermal has the biggest potential. The disadvantage of this is that very few countries are able to tap into geothermal resources. The following countries are the main producers of geothermal power:

United States
Iceland
Kenya
Indonesia
Philippines
Mexico

2. Large Investment Needed
Geothermal power plants are very expensive and often require significant investment. Although they have low running costs, their initial construction cost can be much higher than coal, oil, and gas power plants. A large part of this cost concerns the exploration and drilling for geothermal energy resources. Traditional power stations don’t require exploration and/or drilling.

3. Environmental Impacts
One of the major cons of geothermal energy is the impact it can have on the environment. Below the earth’s surface lies an abundance of gases. Some of these are harmful to the environment and our atmosphere. During the production of geothermal power, these gases sometimes escape into the atmosphere. We have listed the gases in question below. Some of these even contribute to global warming:

Hydrogen Sulfide (H2S)
Carbon Dioxide (CO2)
Ammonia (NH3)
Methane (CH4)
Boron (B)

The process of producing electricity from geothermal energy can also affect water quality. Chemicals used at some facilities occasionally leak and pollute the water table. Although technology exists for the safe use of these chemicals, there is always the potential for leakage to occur. Taking the above into consideration, geothermal energy is still very environmentally friendly.

4. Sustainability Concerns
Human activity can affect the sustainability of geothermal energy. Studies show that without careful management of geothermal reservoirs, they can become depleted. In such cases, geothermal power plants would become useless until the reservoir recovers. Advancements in technology are helping to make sustainability concerns less of an issue. Nowadays, after geothermal fluids have been used, they can be injected back to their source. As a result of this, there is less chance of a geothermal well becoming depleted.

5. Seismic Instability
There is evidence to suggest that geothermal installations have caused earth tremors in various parts of the world. Although often minor, this seismic activity can lead to building damage, injuries, and death. In 2006, scientists blamed a geothermal exploration project in Basel, Switzerland for causing a series of earthquakes. Some of these quakes measured up to 3.4 on the Richter scale. A further study in 2011 found a strong correlation between geothermal exploration and seismic activity. This study focused on the area around the Salton Sea geothermal field in the United States.

Overview
So there we have the pros and cons of geothermal energy. On the plus side, it is renewable, sustainable, environmentally friendly and cost-effective. It also has the advantage of being able to provide a constant power supply, unlike solar or wind.

The downside to geothermal energy is that it can only be used in specific parts of the world. There are also several environmental and safety concerns surrounding the use of geothermal energy.

Some Interesting Facts about Geothermal Energy

These facts provide a good top-level overview of geothermal energy:

• Geothermal energy has been around since the earth formed and is a renewable energy source.
• The term “Geothermal” derives from the Greek words “geo” (meaning earth” and “therme” (meaning heat).
• Geothermal activity provides the energy behind volcanoes, hot springs and geysers.
• Civilizations have been using hot springs heated by geothermal activity for thousands of years.
• Geothermal energy is greater along the fault lines in the earth’s crust as liquid rock (magma) can be found closer to the earth’s surface, thus providing more geothermal activity.
• The best place for geothermal activity is along the “Ring of Fire”.
• Unlike solar, wind and other renewable energy sources, geothermal energy doesn’t rely on solar activity.

Facts specific to geothermal power in producing electricity:

• The process of generating geothermal power has been in existence for over a hundred years and was first tested in Italy by Piero Ginori Conti in 1903.
• Today, geothermal power is only responsible for a small amount of global electricity capacity.
• Modern geothermal power generation is performed at either dry steam, flash steam or binary cycle power stations.
• Geothermal power can be highly price competitive.
• Geothermal power can only be generated cost-effectively in specific areas with enough geothermal activity.
• Geothermal power is considered clean and highly efficient.
• Geothermal power stations do still produce greenhouse gases but on a very small scale when compared with fossil fuel power stations.
• Geothermal power stations are often small and have minimal visual impact on the surrounding environment.
• Geothermal power stations can work both day and night with a high uptime.
• There are over 40 geothermal power plants in the USA alone with many more dotted across the globe.
• In the USA, California has the highest geothermal power capacity and generates just over 80% of the nations geothermal power supply.
• Iceland has the world’s most efficient geothermal power stations and is responsible for a large percentage of global geothermal electricity production.
• Iceland produces around 26% of its electricity supply from geothermal energy.
• New Zealand generates around 13% of its electricity from geothermal activity.
• Other countries that generate significant levels of geothermal power are; Indonesia, Italy, Japan, Kenya, Mexico and Philippines.
• Facts specific to geothermal heating
• These facts are specific to how we can use geothermal energy for heating purposes:
• Geothermal energy can also be used to provide heating for homes. This technique makes use of ground source heat instead of the geothermal activity described above.
• Geothermal heat pumps can be used to produce part or all of a buildings hot water supply.
• Geothermal heat pumps work by burying hundreds of meters of water pipes under ground so that the water absorbs the heat from the earth.

An Overview of the Facts
Geothermal energy is considered as a highly efficient, renewable and environmentally friendly source of energy. We can use this energy to provide electricity through geothermal power stations or to heat our homes through the use of groundwater- source heat pumps. Geothermal energy has been around since the earth formed and man has been known to use this for bathing purposes for thousands of years.