Geothermal, Energy, Cooling, Heat Pumps: FACTS
QUESTION: I moved into an old house which needs a new heating and cooling system. I have heard installing geothermal heating is a good choice today and for the future. Is
geothermal energy good and does it work?
ANSWER: Geothermal energy-heating (heat pump) is extremely energy efficient and generally yields the lowest utility bills of any residential system. In effect, they use renewable solar energy from the sun's rays which get stored in the ground. Geothermal heat pumps also provide the most energy-efficient cooling during summer. Some models can also be combined with solar systems.
In the heating mode, a geothermal heat pumps can produce up to $5 worth of heat for each dollar on your electric bills. Unlike standard heat pumps that lose efficiency and maximum heat output as the outdoor temperature drops, the efficiency and heat output from a geothermal heat pump remains relatively constant.
During summer, a regular heat pump or central air conditioner loses efficiency and cooling output when it is hotter outdoor. Unfortunately, this is when your house requires the greatest cooling capacity. Cooling efficiencies are as high as 30 EER (energy efficiency ratio). A standard heat pump or central air conditioner is typically less than half as efficient.Keep in mind you can qualify for a geothermal tax credit.
Another summertime advantage is free hot water when the geothermal heat pump is cooling your house. Instead of exhausting the heat to the outdoor air through outdoor condenser coils, this waste heat is diverted to your water heater.
A geothermal heat pump operates similarly to a standard heat pump except it exchanges heat with the ground instead of the outdoor air. The temperature of the outdoor air can vary 30 degrees from day to night and more than 100 degrees from the coldest winter night to the hottest summer day. In contrast, the temperature several feet below the ground surface varies relatively little.
In order to capture (winter) the heat energy from the ground or exhaust (summer) the heat during summer, a long pipe is usually buried in the ground. An antifreeze/water solution, running through the pipe, acts as the heat transfer medium. If there is a pond or wells can be dug, this water can run through the heat pump heat exchangers. Many new models use Earth-friendly R410A refrigerant instead of Freon.
Since no outdoor condenser coils and fans are needed, the entire heat pump and all mechanical components are located in an indoor unit. It operates quietly and, with no outdoor fan or compressor, there is no noise to bother neighbors or your family at night. This also reduces wear and tear from constant exposure to outdoor weather and playing children. Read more on geothermal heating cooling