A Steady Flow of Energy
Geothermal heat pump systems utilize the earth’s constant underground temperature to efficiently cool and heat buildings. Specifically, geothermal systems use a network of underground piping that circulates heat exchange fluid to reject or extract thermal energy to and from the earth.
During the summer months, this heat exchange fluid is pumped through the piping and rejects heat collected from the building, via a heat pump(s), into the ground and cools the building. During the winter months, the process is reversed, and heat exchange fluid pumped through the piping absorbs thermal energy from the ground to heat the building. The ability to cool and heat a structure comes from the single underground source.
Balancing Hot and Cold Temperatures
A perfectly balanced building load requires as much heating in the winter as cooling in the summer. This means that an equal amount of heat goes in the ground in the summer as comes out in the winter.
However, perfectly balanced energy loads are rare. In reality, most commercial buildings require more cooling than heating due to high occupancy schedules, large electronic and lighting loads, and solar heat gain. Conversely, residential buildings often require more heating than cooling, depending on location and weather. The fact is that most building loads are not balanced and there is a disparate amount of heat being extracted or rejected into the ground.
When heat is rejected to the ground, the earth stores this heat and acts as a thermal battery waiting to be used. The key to geothermal technology is to use this thermal battery efficiently by ensuring that it is not over or under charged. A properly designed geothermal system takes into account unbalanced loads and will always keep your battery charged.
Fortunately, with advanced technology, systems can be designed and controlled to intelligently balance loads, and existing geothermal systems experiencing temperature issues can be rescued.