Unlike traditional energy sources, geothermal systems utilize the earth sustainably. Though outdoor conditions change with the seasons, underground temperatures usually remain constant. Geothermal systems take advantage of this by tapping into a buried earth loop that capitalizes on these stable temperatures. In winter, fluid running through the buried loops absorbs the heat stored in the ground and sends it to the home. There, the indoor part of the unit compresses the warm air and heats it even more before distributing it throughout the home. During the summer months, the system is reversed and instead pulls heat from the home and carries it outside through the buried earth loops to be distributed back into the cooler soil.
Because they do not rely on the combustion of organic materials to generate heat, geothermal systems produce no emissions and can be 3-4 times more efficient than traditional heat transfer systems. In addition, geothermal systems can provide for base load energy needs because it is a consistent energy source. In the winter, geothermal heat transfer systems can provide consistent heat to homes. In the summer when the system is reversed, it can be counted on to provide a sustainable way to cool a home as well.
Like many renewable energy generation systems, geothermal units can have very high up-front costs. To contrast this high initial cost, geothermal systems are extremely efficient heating and cooling systems that can be depended upon to condition your home consistently no matter the season. In addition, over their 15+ year lifetimes geothermal systems require little to no maintenance to continue operating at a high efficiency. Likewise, the cost of operating a geothermal system is much lower than traditional heating and cooling costs would be. Depending on the model of the geothermal system and your average home energy demand, a geothermal conditioning system can cost as little as $100 per month to operate, which is much, much less than the cost of heating your home with wood in the winter or cooling your home in the summer with window air conditioning units.
One option to offset the increase in electricity demand that accompanies the operation of a geothermal system is to install solar PV panels to provide for the electricity used by the geothermal unit.
A list of ENERGYSTAR geothermal heat pumps can be found at: