Have you ever thought of using the natural heat of the earth to heat your house? It’s actually not a new idea but dates back to the time of the Roman Empire, when people used sources of hot water and steam that were near the earth’s surface to heat buildings. Because of modern technology, people can now use geothermal resources anywhere in the world to heat and cool their houses in an cost-effective way with a geothermal heat pump system!
What is a geothermal heat pump system?
A geothermal heat pump system is a heating and/or cooling system, which uses the earth either as a heat source in the winter or as a heat sink (to put the heat into the ground) in the summer. This is possible because ground temperatures remain stable throughout the year, at around 50-60 F.
This system is also known as “GeoExchange” system and “ground-source heat pump”. Geothermal usually requires a length of buried tubing on the property, a liquid pump back, and a water-source heat pump. There are both open loop systems and closed loop systems. Closed loop systems are more commonly used in households and circulate the fluid through the pipes and exchange heat between the fluid and the earth across the pipe.
- Cut your electricity bills. Geothermal heat pumps systems save from 30% to 70% more energy than conventional systems, because they simply use electricity to move heat from the earth into buildings instead of burning fuels to generate heat. Geothermal heat pump systems thus bring in higher efficiencies, and can be up to 400% more efficient than conventional systems. Studies shows these systems can save the average family from US$400-1400/ year. In the summer, water is heated for free and only for a small cost in the winter.
- Save money in the long run. Geothermal heat pumps systems have a longer life span than conventional systems. Most loop fields are warranted for 25 to 50 years and are expected to last at least 50 to 200 years. You do not have to worry about replacing the system in the short term and once installed, systems can last twice as long as conventional systems.
- Convenient and safe. A closed loop system means no freezing of the flue vents in cold weather when you need heat the most. In addition, there are no gas lines, and therefore no potential for a gas leakage or fire.
- Friendly to the environment. The switch from fuel to geothermal reduces greenhouse gas emissions. There are more than 1,000.000 geothermal heat pumps already installed in the U.S. and the technology has reduced an estimated more than 5.9 million metric tons of CO2 annually and more than 1.6 million metric tons of carbon equivalent annually.
The initial cost of installing a geothermal heat pump system is usually two or three times than of a conventional heating system. However, some electricity companies offer special rates to customers who install geothermal systems, simply because it helps reduce their peak load due to the increased efficiency of heat pumps.
Want to know more?
- National Renewable Energy Laboratory, Geothermal Technologies