What is geothermal energy?

What Is GeoThermal Energy?

What is geothermal energy and how does it work? Geothermal energy is a renewable energy source of thermal energy generated from the heat stored in the Earth.  This heat is a by-product of radioactive decay and residual heat from when God formed the planet.

Finding this heat deep below the Earth’s surface can be difficult, but it has become easier to find these reservoirs thanks to seismic imaging.

Geothermal energy can be found worldwide, with the largest concentrations in the United States and Western Europe.

The temperature below Earth’s surface is relatively constant, but it can vary by location due to changes in geology.

Geothermal energy power plant


Geothermal Energy Sources

You can find geothermal energy in different forms.  There are three main types, each of which are created by the kind of rocks that surround the Earth’s heat source.

Tectonic Plates: In areas with tectonic activity, such as California and Iceland, geothermal energy is derived from hot water and steam reservoirs in areas where the plates meet.Tectonic plates

These systems are also called Hydrothermal Systems and produce some of the hottest water on Earth.

Hot Dry Rock: Areas with hot, dry rock such as Utah and Nevada have seen recent development in this field, but current technology cannot efficiently capture geothermal heat from these reservoirs.

Hot dry rock Utah

When wells are dug into these areas, water is injected into the rock.  The heated water is then taken up in production wells and converted to steam with a geothermal power plant.

This type of energy is often referred to as Engineered Geothermal Systems (EGS) or Enhanced Geothermal Systems by the United States Department of Energy.

Magma: This type of geothermal energy is even rarer than hot, dry rock, but it does exist. Magma (molten rock) accumulates heat as it rises to the surface and can be incredibly hot.Magma

This system has only been tapped on a few occasions, most notably at Larderello, Italy, in 1913.


Geothermal Power Plants

Geothermal energy chimneys

Geothermal power plants are located near areas with high heat flow to make it easier to capture energy.

The process is pretty simple – water is pumped into reservoirs at high pressure, heated by the hot Earth below ground, then brought up in steam form where it spins turbines that create electricity.

The temperature of the water affects the energy output – the hotter the water, the more power generated.

Currently, these plants can supply about four gigawatts of electricity worldwide.  The largest in operation is The Geysers in California and Hellisheidi in Iceland.

Iceland has five geothermal power plants to generate 25 per cent of its electricity and prides itself on being a pioneer in this type of energy.

Geothermal energy is reliable but expensive. In addition, maintenance costs can be high.


Uses Of Geothermal Energy

Some uses of this energy include heating buildings, heating water for use in showers or stoves, and the creation of electricity.

Geothermal energy has also been used to create direct heat, which you can use in winter sports such as Ice Skating, Ice Hockey, Skiing/Snowboarding etc.



The advantages are that geothermal energy is easily accessible and can be used for residential heating. In addition, it has the potential to generate electricity, but this process is more expensive than traditional energy sources.

The use of geothermal energy helps reduce greenhouse gas emissions by not relying on fossil fuels. It takes only a few months before an initial investment in geothermal heating pays off.



The disadvantages are that this energy source can be unreliable due to inconsistency in temperature levels.

It is difficult to predict how much geothermal heating will cost because many factors must be considered, including the size of the property and the availability of underground resources.

Finally, the installation process is expensive and requires specialized equipment.




How Is Geothermal Energy Generated?

This energy is taken from the Earth’s natural heat, ranging between 45 degrees Celsius to 600 degrees Celsius.  Heat is extracted by using wells that are dug deep into the Earth.  It is then transported via pipes and water to geothermal power plants where electricity or heating is generated.


How Is Geothermal Energy Used?

You can use this energy in many different ways. The most common uses are heating buildings and water, but geothermal energy can also create electricity.  It is becoming more popular for direct heat, a source of power that makes snow on ski hills so people may participate in winter sports.


Is Geothermal Energy Renewable?

Yes, it is! A significant advantage of this energy source is that they are renewable. The heat found below the Earth has been accumulating since the Earth was formed, so this energy source will not run out anytime soon.


How Does Geothermal Energy Work?

It works by transferring heat from the Earth’s core to air or water.  You can do this in many ways, but power plants and residential use are the most popular.

This energy is used to create electricity through turbines that spin when hot fluids move through them at power plants.

The hot fluid is pumped to the surface, where it heats air and water.  The heated air and water are then used as a source of power.

You can use this energy for heating and hot water in homes depending on the systems in place.


Where Is Geothermal Energy Found?

This energy source is found all over the world. However, the most significant reserves are deep below Earth’s surface, primarily around tectonic plate boundaries where the crust is thin and at high temperatures.


How Much Does Geothermal Energy Cost?

Estimated costs for geothermal heating will depend on several factors, including your location, type of property, and amount of resources.  The costs can range from a few dollars/month to thousands of dollars/month, depending on how many resources are available in your area.

How Does Geothermal Energy Affect The Environment?

Geothermal energy is a clean source of electricity generation because no fuel is burned when the heat from below the Earth creates electricity.  Geothermal heat sources also emit very few greenhouse gases, making them a better energy source when compared to burning natural gas or coal.

The biggest problem with this energy source is that drawing up the heat from deep below the Earth’s crust can cause earthquakes and other hazards for those living nearby.

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