Advantages and Disadvantages of Geothermal Energy (Pros & Cons)

As we continue our exploration of viable, clean energy sources, geothermal energy is up next on the list.

Geothermal energy is quite different from more commonly known renewable energy sources such as solar and wind. Instead of harnessing the power of the sun, it draws from the internal heat source of the Earth.

Power plants that generate geothermal electricity use steam produced from naturally occurring reservoirs of hot water, which can be found some miles below the Earth’s surface.

Think of these reservoirs as hot springs, except much further into the ground.

The hot water from these pools turns into steam that rotates a turbine. The turbine then powers a generator, which creates electricity.

There is enormous potential for geothermal to aid in meeting the population’s rapidly growing energy demands.

As always, though, there are downsides that must be considered. You can imagine that pulling energy from below the Earth’s surface isn’t as easy as people make it seem.

Complications arise that effect both the environment and pockets of those who utilize the energy.

Below, we’ll discuss in more detail the pros and cons of geothermal energy.

Advantages of Geothermal Energy (Pros)

Geothermal energy is another renewable, mostly green energy source. As long as the Earth exists, there will be the opportunity to draw from its internal heat.

While the nature of geothermal energy is often what differentiates it from solar and wind, there’s also one other thing of note – geothermal is very reliable.

Solar and wind energy are largely considered unpredictable. You can’t always estimate how much energy can be produced on a given day. With geothermal, however, it’s actually very predictable.

These are just a few of the upsides to geothermal energy. Let’s now explore these and more in greater detail.

1. Renewable.

For as long as the Earth exists, there will be geothermal energy to harness. This puts it in the renewable category along with solar and wind, and it will be around until the sun swallows us whole in about another 5 billion years.

The hot reservoirs used to extract geothermal energy are natural resources within the Earth. Unlike fossil fuels such as coal and natural gas, they are naturally replenished.

This makes geothermal not only renewable but also sustainable. There is a caveat to this that we’ll discuss in the cons, but for the most part, it is largely considered a renewable and sustainable resource.

2. Mostly Environment Friendly.

Geothermal energy is most commonly referred to as a green energy source. This means its impact on the environment is minimal.

Producing geothermal energy does create some pollution, which we’ll discuss later in the cons. However, its carbon footprint is rather tiny in comparison to fossil fuel energy production.

Whether or not you believe in global warming, geothermal energy advancement will be a strong candidate as a part of Earth’s long-term energy solution.

3. Reliable.

Contrary to solar and wind, geothermal energy is a very predictable source of energy. Geothermal power plants have a power output that can be easily calculated with a high level of accuracy.

We don’t have to worry about the fluctuation of wind, overcast days, or total darkness. Geothermal energy is able to be produced around the clock with minimal interruption.

This is a very important factor to consider, and it means that geothermal energy is acceptable for meeting base load energy demand. In simpler terms, people need a certain amount of energy during the day, and geothermal can reliably supply it without concern.

4. Does Not Require Fuel.

Usually when you think of power plants, you think of needing lots of fuel. Not the case for geothermal energy.

Similar to solar and wind, geothermal energy is produced by nature. It is not consumed, but rather it is harnessed and converted to electricity.

This goes back to it being a renewable and sustainable energy source. It also means that we don’t have to worry about activities such as mining that come with a heavy price tag of pollution into the environment.

5. Strong Upside for Homeowners.

Over the last few years, there has been a significant increase in demand for geothermal heating and cooling for personal homes.

As a renewable and green energy source, it proves to be an attractive option for many.

While it might be on the expensive side to get started, the costs are typically recouped several years down the road.

Currently, how expensive are your electric and gas bills throughout the course of a year? If you’re like most, they typically fluctuate heavily with the different seasons.

Geothermal energy provides significant savings year round on both heating and cooling costs. Again, you just have to be willing to make the upfront investment.

6. Rapidly Evolving Technology.

On par with other green energy sources, geothermal energy is at the forefront of exploration.

New technology continues to come out that improves the energy production process, which makes it a more attractive option as the years go by.

There are a number of cons that we’ll discuss in the paragraphs to come. Keep in mind that technological advancements have the ability to negate some of these downsides and potentially turn them into advantages.

It will be interesting to see what society can come up with as we continue to dive further into geothermal energy research.

Disadvantages of Geothermal Energy (Cons)

Like any energy source, the pros are typically accompanied by cons, which is precisely why we put this article together.

As you can imagine, humans don’t have much control on where Earth decides to hide its hot water reservoirs. This makes location a tricky issue.

When you add high upfront costs, the potential for earthquakes (yes, we’re serious), and a few issues with sustainability, you’ve got yourself an energy source debate.

These and a couple others are the cons which we’ll now discuss in more detail below.

1. Zone Specific.

Probably the biggest disadvantage to geothermal energy is that it’s incredibly location specific. We don’t really have the power to choose where we construct geothermal power plants, which leads to rather inconvenient locations being forced upon us.

As a result, there are only certain zones where geothermal power is an option. More often than not, these zones are far away from cities and towns.

That means geothermal will probably never be a viable option for wide-scale energy production.

It has plenty of advantages if you happen to be in area where it can be harnessed, but outside of that, it’s very lackluster.

2. Environmental Side Effects.

While the production of geothermal energy typically doesn’t release any greenhouse gases, there are plenty below the Earth’s surface that can’t be ignored.

During the digging process, these gases are often released into the atmosphere. Yes, this does tend to happen even without human interference, but emissions have been shown to be higher within close proximity to geothermal plants.

In general, pollution created by geothermal power plants is considered low in comparison to traditional fossil fuel plants today.

While these environmental side effects are considered a con, they don’t have nearly the impact of energy sources we currently use today.

3. Earthquakes.

What? Yes, you read that right. Geothermal energy has become notorious for triggering earthquakes.

Anytime you’re dealing with heavy digging deep under the Earth’s surface, there’s the potential of altering its structure. This can lead to tectonic shifts large enough to cause earthquakes.

For the most part, these earthquakes aren’t dangerous due to the location of most geothermal power plants. However, any type of natural disaster usually comes with the potential for life-threatening accidents.

Other energy sources don’t have this issue at all, which can be a big hindrance for geothermal energy advocates.

4. High Upfront Costs.

With geothermal, there are high price tags that have to be considered.

First is the cost of building a commercial power plant. Similar to nuclear, they can be very expensive. You can imagine that drilling holes several miles into the Earth’s surface can be rather pricy and time consuming.

The unfortunate reality is that geothermal energy is struggling to compete with other energy production methods. Even though you save money utilizing it in the long run, the high upfront costs are a major deterrent.

Much like wind, most geothermal energy users are given significant subsidies to make use of the energy source. Until technology improves, this is likely to stay the case for at least the next several years.

5. Issues with Sustainability.

For the most part, geothermal energy is considered a sustainable energy source. That’s why we listed it high in the pros section.

We produce geothermal energy by taking hot water from Earth’s reservoirs. These reservoirs are replenished when rainwater makes it way down from the surface.

In theory, if we use the fluid at a faster rate than it is replaced, then we will eventually deplete the supply. This just means that geothermal power has to be effectively managed.

It’s worth noting that sustainability is only an issue for geothermal power plants. Geothermal energy is used differently for the heating and cooling of homes, which makes this a nonfactor.


By now it’s hopefully clear that a long-term plan for meeting Earth’s energy demands isn’t a one-man show. It’s going to be a combination of different renewable, clean, and green energy sources that we can use for generations to come.

Geothermal energy is without a doubt one of those energy sources that must be considered.

Besides being renewable and mostly sustainable, it’s also very reliable, doesn’t require fuel, and has a strong upside for residential homeowners.

Geothermal energy’s downsides include high initial investments, very location specific energy, and some potentially dangerous environmental side effects, including earthquakes.

After reading through the lists of pros and cons, what are your thoughts?


Featured Image Credit: Idaho National Laboratory @ Flickr