Geothermal power

The Earth is very hot inside.

We can use that heat to make power. This heat comes from deep underground.

Hot water or steam moves to the surface. This steam turns a large wheel. The wheel makes electricity for our homes.

This is a good way to get energy. It is a clean way to work. It does not make much dirty air. It is a way to get power that lasts.

Many lands use this heat today. Some lands use it for heat too.

It is a very smart way to use our world.

The Earth is very hot inside. We can use this heat to make electricity. This is called geothermal power.

Heat from deep underground moves to the surface. It travels through water or steam. This heat can turn a turbine. A turbine is a large wheel that spins. As it spins, it powers a generator to make electricity.

There are different ways to make this power. Dry steam stations are the oldest type. They use steam directly from the ground. Other stations use flash steam. Some use a binary cycle. This uses a special liquid to help make power.

Geothermal power is a renewable source. This means it can last a long time. We use only a tiny bit of the Earth's heat. It also keeps the air cleaner than coal plants. Many countries use it. The United States and Indonesia use a lot.

We may use even more of this power in the future.

Geothermal power is a way to make electricity using heat from inside the Earth. This energy is considered renewable and sustainable. This is because the amount of heat we take out is very small compared to the Earth's total heat.

Using this heat helps keep the air cleaner too. Geothermal plants release much less carbon dioxide than coal plants do. In fact, they release less than 5% of the gases that coal plants do. As of 2019, the world had 15.4 gigawatts of this power capacity.

How does this work? It all starts with heat deep underground. This heat can move to the surface through water or steam.

In a dry steam station, steam comes straight from the ground to turn a turbine. A turbine is a large wheel that spins when the steam hits it. As the turbine spins, it powers a generator to make electricity. Some stations use a binary cycle. This uses a special liquid to help move the heat. The liquid is heated, turns into a gas, and spins the turbine.

People have been finding ways to use this heat for a long time. In 1904, Prince Piero Ginori Conti tested the first generator in Italy. It was a small test that lit up four light bulbs.

Later, in 1911, the first commercial station was built in that same place. By 1958, New Zealand became a major producer with its Wairakei station. In 1960, the United States started its first successful station at The Geysers in California. That original turbine worked for more than 30 years.

Many different countries use geothermal energy today. About 26 countries use it to make electricity.

Iceland, Kenya, and the Philippines are some places that get a lot of their power from the Earth. Indonesia has the largest potential in the whole world. In 2017, Indonesia had an installed capacity of 1.8 gigawatts. The United States also uses a lot of this power. About 23.9% of the world's geothermal power is installed in the United States.

Geothermal energy is a big part of how we power our world. It is different from wind or solar power because it does not change as much. This means it can provide a steady flow of electricity. Experts believe we could meet 10% of the world's demand by the year 2100.

New technology might even let us use heat from much deeper underground. This could help us reach even more energy in the future. We are still learning how to tap into the Earth's huge heat supply.

Geothermal power is the process of generating electricity from the heat found within the Earth. This energy source is considered renewable and sustainable. This is because the amount of heat humans extract is very small compared to the Earth's total heat content.

Using this heat is also cleaner for the atmosphere. Geothermal electric stations produce an average of 45 grams of carbon dioxide per kilowatt-hour. This is less than 5% of the emissions produced by conventional coal-fired plants. As of 2019, the total worldwide geothermal power capacity reached 15.4 gigawatts (GW).

The mechanism of geothermal power relies on transferring heat from the Earth to a working fluid. This fluid is used to turn a turbine, which then powers a generator to create electricity. The Earth's crust acts like a thick insulating blanket. To release the heat underneath, we must pierce this blanket with fluid conduits like magma or water. Heat naturally flows to the surface through conduction at a rate of 44.2 terawatts (TW). It is also replenished by radioactive decay at a rate of 30 TW. This heat must be carried to the surface through circulation. This can happen naturally through hot springs or by drilling wells into hot aquifers.

Engineers use different technologies to capture this heat depending on the available resources. Dry steam power stations are the simplest and oldest design. They require a resource that produces only dry steam. In these stations, geothermal steam of 150°C or higher is used directly to turn turbines. After the steam turns the turbine, it enters a condenser. There, it turns back into a liquid and is sent back into deep wells to be reheated. Flash steam power stations are another type used to harness high-temperature resources.

A third method is the binary cycle power station. This technology allows for the use of much lower temperature resources. It was first demonstrated in the Soviet Union in 1967. In these systems, an organic fluid is used to carry the heat. This fluid is heated by the geothermal water, turns into a gas, and spins the turbine. A binary cycle station in Chena Hot Springs, Alaska, produced electricity from a record low fluid temperature in 2006. This technology is vital because it expands the areas where we can generate power.

The history of geothermal energy began in the early 20th century. Prince Piero Ginori Conti tested the first geothermal power generator on July 4, 1904, in Larderello, Italy. That successful test lit four light bulbs. The world's first commercial geothermal power station was built in Larderello in 1911. Italy remained the only industrial producer of geothermal electricity until 1958. In that year, New Zealand became the second major producer when the Wairakei station opened. Wairakei was notable for being the first station to use flash steam technology.

Today, geothermal energy is a significant global resource. Geothermal electricity is currently used in 26 countries, while geothermal heating is used in 70 countries. The United States holds 23.9% of the world's installed capacity, which is 3.68 GW. Some countries, like El Salvador, Kenya, the Philippines, Iceland, New Zealand, and Costa Rica, generate more than 15% of their electricity from geothermal sources. Indonesia has the largest estimated potential in the world at 29 GW. In 2017, Indonesia's installed capacity was 1.8 GW.

Future developments may focus on enhanced geothermal systems (EGS). This approach is used in ground that is hot but dry or lacks water pressure. Developers bore two holes into a site and fracture the rock between them. They then pump water or liquefied carbon dioxide down one hole so it comes up the other as a gas. This could unlock much more energy than tapping natural aquifers. While the thermal efficiency of these stations is relatively low, around 7% to 10%, they are very reliable. Unlike wind or solar, geothermal power does not rely on variable sources. This allows for a high capacity factor, which reached a global average of 74.5% in 2008.