The Ground Source (Geothermal) Heat Pump
How to Pay Less for Heating or Cooling and Help Save the Planet Too
Dec 30, 2008
Many people think of geothermal energy as a form of energy that can only be used in certain geologically active areas and under special circumstances. But ground source heat pumps (GSHPs) are a type of geothermal energy technology that can be utilized almost anywhere.
A geothermal heat pump can be cheaper than conventional systems if incorporated into the financing of the house. Even if paid for "out of pocket," the cost is comparable to the average cost of a kitchen or bathroom renovation in the United States and will pay for itself within a few years in reduced utility bills.
Constant Underground Temperature Fuels the System.
The simple principle behind the efficiency of the ground source heat pump is that the temperature below the ground remains relatively constant no matter how extreme the surface air temperature is. This can be seen in caves and cellars. For example, the temperature in Mammoth Cave in the United States, as reported by the National Park Service, remains about 54 degrees Fahrenheit (12 degrees Celsius) year round.
The temperature of the ground six feet below a house is likely to be between 45 and 75 degrees Fahrenheit (7 to 24 degrees Celsius), no matter where it is. What this means is that the heat pump does not have to work very hard to cool off the air in the house in summer or heat it up in winter. As the house air passes through the system into the ground, the constant ground temperature provides 70 percent of the energy to operate the system, and this energy is "renewable," which means for the homeowner it is free.
Quiet, Weather-Resistant, Conventional in Design and Popular Among Owners.
Since they have no condensing units, geothermal heat pumps are also quiet relative to other heating and cooling (HVAC) technologies. Because most of the system is below the ground, it is not subject to weather damage. Other than the unit itself, the system can have a conventional design for pumping air through the house. According to the California Energy Commission (CEC), studies show that 95% of homeowners who have geothermal heat pumps would recommend them to their family and friends.
Cheaper than Conventional Systems and Will Pay for Itself.
The upfront cost for installing a geothermal heating and cooling system varies depending on the size of the building and other factors and may initially be more expensive than other systems. As the technology improves, these costs continue to fall. But if the homeowner obtains an Energy Efficient Loan prior to installing the system, it could actually cost less to install than more conventional heating and cooling systems. Over the long term, the GSHP will always be cheaper.
Other financial incentives to this type of energy-saving investment also exist (see North Carolina State University's Database of State Incentives for Renewables and Efficiency at www.dsireusa.org for more information). Even in the absence of financing, a GSHP is so efficient that it ends up paying for itself in energy savings within a few years.
Potentially Revolutionizing Technology.
Geothermal heat pumps are a potentially revolutionizing, yet underutilized, technology in America. Experts think this is mainly because most people are unaware of the benefits of owning one. The U.S. Department of Energy wants the United States to have many more units in operation because if GSHPs should become widespread, they could save consumers hundreds of millions of dollars per year in energy bills and reduce yearly greenhouse gas emissions by millions of metric tons.
For more information or to find a contractor, visit the Geothermal Heat Pump Consortium's Web site at www.geoexchange.org. In Canada, visit Natural Resources Canada at http://oee.nrcan.gc.ca/residential/business/energystar/procurement//geothermal.cfm.
 |
