For more than 60 years, geothermal systems have been a useful resource for lowering energy bills in different building styles including commercial, industrial and residential. Today, these types of systems are becoming even more common in eco-friendly buildings as part of the growing green building movement.
Geothermal systems work by utilizing the Earth’s temperatures from four to six feet underground, where the temperature remains relatively constant year-round. Geothermal systems use a geothermal heat pump, which disperses heat from the ground in the winter and into the ground during the summer.
The system contains three main components including the heat-pump unit, the liquid heat exchange medium, and the air-delivery system and/or the radiant heating. Along with the components, the geothermal system includes a group of polyethylene pipes buried underground to create what is called an earth loop. The pipes can be buried horizontally or vertically depending on the project needs. To provide geothermal heat, cooling, and hot water, water circulates in the earth loop to exchange heat between your building, the ground source heat pump, and the Earth.
In the winter, the fluid flows through the system’s Earth loop, absorbing heat from the ground and carrying it indoors. From there, the indoor unit compresses the heat to a higher temperature and distributes it throughout the building. In the summer, the geothermal HVAC system pulls heat from the building and carries it through the Earth loop to a reinjection well, where it deposits the heat into the cooler earth.
The main difference between geothermal systems and other systems is that geothermal systems do not burn fossil fuels to generate heat, nor do they emit greenhouse gasses. It is efficient for building heating and cooling and requires little maintenance, often lasting for decades if installed correctly. Geothermal systems utilize clean, renewable resources and can be submitted for LEED credits.
Although geothermal systems do have hefty installation costs compared to regular HVAC systems, the benefits and cost savings from heating and cooling can make up for it in the long run.