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Geothermal Power: A Renewable Energy Source

Geothermal power is yet another form of renewable energy. While it isn’t entirely green energy, it is still a much better method of energy and electricity production than what we are currently using.

Unfortunately, there are some downsides, since geothermal energy is the easiest and most cost-efficient to access where there is a lot of tectonic activity. This means that anywhere there are hot springs or volcanoes, you can potentially harvest geothermal energy.

What is Geothermal Energy?

Geothermal energy is defined as the heat inside the earth. Due to the earth’s magma core, geothermal energy is a renewable energy source. The magma core will continue to produce heat, so it doesn’t matter how much we use it. 

Four Basic Types of Geothermal Energy Technology

This is a little misleading. There are four different types of geological formations from which we can extract geothermal energy, but only three main types of geothermal power plants. 

geothermal power

The four geothermal formations we can use are: 

  • Geopressurized
  • Hot, dry rock
  • Magma
  • Hydrothermal

Out of all of these, hydrothermal is the one we use the most throughout the world. They consist of hot water or steam that is inside porous rock and trapped in place by a non-porous rock above.

They are often used to directly heat homes, buildings, and pools, but the steam can also be used to produce electricity. Magma is somewhat molten rock. This is the largest source of geothermal energy but is found in deep depths between two to six miles below the surface.

The depth and the temperature of the magma can reach 2,192 degrees Fahrenheit. Hot, dry rocks are usually impermeable rocks that are at shallow depths.

While there are hot, dry rocks deeper in the earth, anything below about two miles is considered to be non-economical with the technology we have at the moment. To get energy from these rocks, they have to be fractured and water is heated from the fractures of the rock. 

Finally, you have geopressurized geological formations. In these formations, fairly high temperatures are trapped in permeable rock but are held in place due to pressure.

They usually create a brine of salt, minerals, and methane gas. Essentially, this means that not only can these brines be used to produce electricity, but important minerals can be extracted as well.

As for the power plants designed to take geothermal energy and transfer it into power, there are three of them. These are:

  • Dry steam
  • Binary cycle
  • Flash steam 

In the United States, there is only one area where dry steam occurs, and this is at the Geysers in northern California. While the Yellowstone National Park in Wyoming could potentially produce dry steam that we could put through a plant to make energy, it is a protected area, so development isn’t allowed. 

Dry steam works by drawing steam out of the ground. It is piped from an underground well to a power plant where a turbine and generator are waiting to be turned. 

Binary steam is used where temperatures aren’t very hot, usually below 360 degrees Fahrenheit. This method works by taking the heat from hot water to boil an organic compound that has a low boiling point.

This heat transfer causes the other fluid to vaporize, which then in turn spins the turbines. The water is returned to the earth to heat up via drilling holes, making the water a renewable resource. 

Flash steam is the most common plant. It works with water where the temperatures reach above 360 degrees Fahrenheit. Because of the natural pressure, the hot water flowers upwards of its own accord, and starts to turn into steam along the way via convection.

energy savings on geothermal energy

Then, the steam and the water are separated. The heat and the steam then go to create circulation around the turbines and generator. 

What Is Geothermal Power?

Geothermal power is the power we get from converting geothermal energy from its natural state into electricity and heat that we can use. It is considered a renewable resource that can be found below the crust, or surface of the earth. 

The water, magma, or steam is created thanks to the core of our planet, which is the hottest part of our planet. Most of this energy is stored somewhere in the mantle, which consists of everything between the outer core and the crust. 

How Is Geothermal Power Used?

Without converting it into electricity, geothermal power can be used to heat and cool buildings, homes, and even pools. However, the steam created by heated water or heating water by moving it through cracks in hot rocks can turn turbines, which in turn spin generators that create energy. 

What Are the Benefits of Geothermal Power?

There is a lot of potential for geothermal energy. Some of the positives include:

  • Environmentally friendly
  • Sustainable
  • Reliable
  • No fuel needed
  • Stable
  • Renewable
  • Heating and Cooling
  • Rapid Evolution

What Are the Drawbacks of Geothermal Power?

Statistically, no form of energy can be perfect. There are drawbacks to all forms of producing electricity. Some examples of the drawbacks of geothermal power include:

  • Restricted by location
  • Environmental side effects such as releasing of gas 
  • Earthquakes
  • High costs
  • Not always sustainable

How Is Geothermal Power Generated?

Geothermal energy is naturally generated from the earth. This energy is then converted into power, generally by steam which turns turbines and generators by extension. 

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How Does Geothermal Power Compare to Other Renewable Energy Sources?

Geothermal energy has some high upfront costs. Each plant can cost $2 to $7 million, just to hold a one-megawatt capacity. Additionally, while it can be fairly sustainable, there must be constant management to make sure that practices are performed correctly.

As an example, water has to be pushed back into the earth at a rate faster than it is depleted. Unlike some other forms of energy, geothermal power isn’t wholly clean. It does release greenhouse gasses back into the atmosphere during the process.

While it isn’t as bad as burning fossil fuels and harvesting natural gas, there are cleaner options.


geothermal power

Finally, since geothermal energy has to be harvested where the energy is present, geothermal power plants can’t just be put anywhere. They are restricted to certain locations, which means using them across the world isn’t feasible. 

How Does Geothermal Power Compare to Fossil Fuels?

However, geothermal energy is a reliable source of power, it needs no fuel, it is renewable, and it is still more environmentally friendly than what we are currently using. While it isn’t perfect, it is an ideal stepping stone from our current source of power to more sustainable ones.

What Is the Future of Geothermal Power?

If geothermal energy can overcome some of its more technical and financial barriers, geothermal methods used to create electricity could see an increase of about 26-fold by 2050. Plus, using geothermal energies as a way to naturally heat and cool buildings and homes can reduce our electricity demand, making it easier for other forms of energy to step in. 

How Can I Use Geothermal Power in My Home?

For homes, the most common way currently to use geothermal power is as a heating and cooling source. If done right, a geothermal HVAC system can keep your home warmer in the winter and cooler in the summer by moving around heat from underground. 

What Are Some Geothermal Power Plants Around the World?

Some of the biggest geothermal power plants around the world are:

  • Malitbog Geothermal Power Station, Philippines
  • Calenergy Generation’s Salton Sea Geothermal Plants, US
  • Cerro Prieto Geothermal Power Station, Mexico
  • Larderello Geothermal Complex, Italy
  • The Geysers Geothermal Complex, US


What is geothermal power?

Energy extracted from the Earth’s interior heat is known as geothermal energy, and it is a renewable resource. Geothermal power plants may tap into this resource by converting heat and steam into energy.

Geothermal power is generated by using geothermal energy to create electricity, and it is a renewable energy source that has the potential to be both clean and efficient.

How is geothermal power generated?

Geothermal energy, which is produced by tapping the Earth’s interior heat, is a renewable source of power. The system generates energy by harnessing the steam and heat present at extremely low surface temperatures under the earth.

Electricity is generated by a turbine or generator that uses the heat and steam accessed by digging into the Earth’s surface.

What are the benefits of geothermal power?

Geothermal power is:
– Safe
– Reliable
– Renewable
– Low risk
– Full of potential

What are the drawbacks of geothermal power?

However, the drawbacks of geothermal power are that it is:
– Only applicable to certain regions
– Expensive to start up
– Able to create instability of the surface
– Not a very clean source of energy
– Hard to distribute power around

How much does geothermal power cost?

Geothermal power has a high start-up cost, but after that, it can be relatively cheap. Generally, geothermal power can cost anywhere between 0.1 to 0.3 cents per kilowatt hour. This puts it a little bit cheaper than or the same price as fossil fuel energy. 

How efficient is geothermal power?

Geothermal energy is incredibly efficient. It can stay above 90% efficiency most, if not all, of the time. While it can potentially go as high as 98%, that can increase the costs of electricity as more maintenance is required. 

What is the carbon footprint of geothermal power?

While geothermal energy and power aren’t 100% clean, it isn’t as bad as current fossil fuels or natural gas. Using geothermal power releases about 38 grams of carbon dioxide per kilowatt hour, which is considered a very low amount. 

How much land is required for a geothermal power plant?

Per megawatt, a geothermal field uses about one to eight acres. This is pretty small considering coal plants need about 19 acres and a nuclear plant needs five to ten acres for the same amount of power. 

This is partly due to the efficiency, but also because most geothermal energy is underground

What is the lifespan of a geothermal power plant?

The typical lifespan of a geothermal system is greater than 24 years. However, the geothermal system itself, which includes the heating and cooling equipment, may endure for up to fifty years with proper maintenance.

This means that the equipment used to power the geothermal system may be utilized for a lot longer than the system itself (which may need to be replaced after 24 years).

Are there any geothermal power plants in operation in the United States?

In the United States, there are about 64 geothermal power plants. This provides about 2,700 megawatts of power. Unfortunately, because most power plants have to be on or near tectonic plates, most of them are in the western part of the country or Hawaii.

Does geothermal energy involve solar energy?

Geothermal energy is a form of renewable energy that is derived from the Earth’s internal heat. It is generated by the natural decay of radioactive elements in the Earth’s core and is harnessed through a variety of technologies that use the Earth’s internal heat to generate electricity.

While geothermal energy is not directly related to solar energy, it is a form of renewable energy that can be used as an alternative to fossil fuels. Additionally, some geothermal systems use the sun’s energy to heat the Earth’s surface, which can then be used to generate electricity. In this way, geothermal energy can indirectly involve the use of solar energy.