Ground source heat pumps use the ground's geothermal energy as a stable source of heat and cold. While they are very energy efficient, there are some inherent disadvantages associated with them. By understanding the disadvantages of a ground source heat pump, you will be able to make an informed decision before installing one.
According to Cogeneration Services, the initial cost of installation is higher than installing a conventional furnace and central air conditioner. Trenches have to be dug, or well holes drilled. For trenches, a lot of dirt has to be moved, and you will have to rent a large backhoe or contract an earth moving company. For well holes, you either have to rent a well derrick or contract a well driller, who usually charges by the drilled foot.
As of 2010, a ground source heat pump is relatively new technology. Not all contractors are familiar with it, but yet many unethical contractors will tell you they are old pros at installing one. If installed incorrectly, the heat pump will simply not work right. Finding a qualified installation contractor may be difficult, since the contracting field is chock-full of charlatans.
Subsurface geology may make installation of the heat transfer pipes difficult. If you have very rocky soil, huge subterranean boulders may be encountered during the digging or drilling process. The removal of them may be time consuming, and earth moving companies will charge according to the amount of labour needed.
According to Home Energy Magazine, regional issues arise when dealing with claims of super energy efficiency. Home Energy states that in the northeast regions of the country, the energy savings claimed may not be accurate. Rather, the energy consumption is comparable to conventional systems, which cost considerably less to install. If you heat water with the geothermal heat pump as well, the overall system's annual utility costs may be higher than conventional systems in the New England area.