top of page

What is Geothermal?

Updated: Aug 9, 2019

Renewable energy has taken the world by storm. We see solar panels stacked atop buildings and wind farms dominating open fields, but what about the sources we can’t see? Geothermal energy uses heat from inside the Earth’s layers to produce electricity. While we cannot see the 42 megawatts of power flowing from inside the Earth’s magma rich interior, the effects of this excess energy erupt onto the Earth’s surface in the form of volcanoes and geysers.

Geothermal is a renewable energy source that can be used to generate power plants or directly power homes and businesses. According to the U.S. Department of Energy, geothermal HVAC systems are the most efficient way of heating and cooling and can represent an energy reduction of 25 to 70 percent depending on the region. Unlike wind and solar energy generation, geothermal is constantly available making it a reliable and essentially limitless source of electricity.

There are two main ways to take advantage of geothermal energy; district heating systems and geothermal heat pumps. A district heating system is used to provide electricity to a geothermal power plant. Underneath the Earth’s surface, ground water combines with geothermal energy to produce geothermal reservoirs. With the help of large wells, the geothermal energy is brought to the surface where it can be converted to electricity. Geothermal heat pumps, on the other hand, use the constant temperatures found near the Earth’s surface to heat and cool buildings. Regardless of outside temperature, the ground just 10 feet below the surface stays at a constant temperature of around 50 to 60 degrees Fahrenheit.

A geothermal heat pump consists of a loop of pipes buried underground. The pipes are filled with a liquid that circulates through the loops to absorb the Earth’s heat. The heat is transferred into the building where the warm air can be circulated. In the summer, the heat pumps work in reverse, because the ground underneath the Earth’s surface remains cooler than the hot outside air. The geothermal heat pump takes the hot air from inside your building, transfers it through the underground loops to cool, and recirculates it throughout the building.

While renewable energy is an important piece of clean energy, it’s not the first step. Before turning to renewable energy, ensure your building is energy efficient. We can help you tune-up your building to save energy and reduce costs. To learn more about how to get started in energy efficiency, contact us at 312-265-3971 or


bottom of page