The heat of the Earth makes up what is known as geothermal energy. When dust and gasses from Earth mixed together 4 billion years ago, geothermal energy resulted.

Inside the Earth at its core, some 4, 000 miles deep, the temperature is estimated at about 9,000 degrees Fahrenheit. Geothermal energy has been used throughout history for bathing, relaxing, cooking and heating. It was thought by some to have healing effects and was used to treat eye and skin diseases. The first geothermal generator that produced energy was built in Lardarello, Italy in 1904. The United States followed with their first attempt at geothermal power in 1912 at The Geysers in California. Today it is produced in twenty-one countries around the world.

Geothermal energy is located deep in the ground. The heat at the core of the Earth has an outward flow. As it moves, it is transferred to surrounding rock layers called the mantle. As temperatures and pressure increase, the rock melts and becomes magma. The magma moves toward the surface of the earth carrying the heat with it. If the magma reaches the Earth’s surface, it becomes lava. However, most of it stays below the Earth’s crust and heats rocks and water that surround it. These temperatures can reach up to 700 degrees Fahrenheit. When the water travels to the Earth’s surface, it becomes hot springs or geysers. Mostly it stays trapped in fractured, porous rocks called geothermal reservoirs. This heat near the Earth’s surface becomes a form of energy.

Hot water or steam from the reservoir exerts a force that can spin a turbine connected to a generator and produces electricity. The cooled water is then returned to the reservoir in order for it to reheat. Much exploration and testing needs to be done to determine where the geothermal underground waters are. When ideal spots are located, drilling is done to create production wells that bring the water to the Earth’s surface for power generation in geothermal power plants.

Although the costs to construct geothermal plants and geothermal wells are high, the cost of producing electricity is lower over time. The fuel is reliable, stable and does not need to be transported. The white smoke you will see over geothermal power plants is not smoke but rather steam. During the process of operations it may, however, bring some hazardous gases from underground.

The United States stands as the biggest producer of geothermal energy. Unfortunately, interest in it is low and it only accounts for about 1% of this country’s energy supply. Through research and experience new methods and technologies for accessing geothermal energy will improve. Tapping into the heat under the Earth’s surface can produce much more of the nations energy. We are at a point where renewable energy sources must make their way to the forefront of the energy picture. Not only are fossil fuels being depleted, but also they are ruining our air quality. In time, geothermal energy may become an appealing alternative. Competitive pricing and minimal environmental impact could produce a hot future for this renewable energy source.