The well drilling rig in the middle of a neighborhood may have seemed an unusual sight last week; but, it was not actually drilling for water. Instead, owner Frank Glass and his crew from Western Water Wells were drilling 200 foot holes, not wells, for a new geothermal heat pump system that will be part of the newest Habitat home on Loving Street.
A geothermal heat pump is much like the typical heat pump one encounters in many homes today. The big difference is that instead of using the outdoor unit with the coils and fan to exchange heat with the outside air, a geothermal systems utilizes the earth instead of the air. The earth absorbs almost 50% of all solar energy and remains a nearly constant temperature of 50°F to 70°F depending on geographic location.
The geothermal system for this home utilizes a series of drilled holes with a combined depth of 400 feet (two 200 foot holes).
Habitat does not require or use any of the water that may be present. They just need enough earth surface to effectively transfer to and from the formation. Each hole has two tubes with a “U” connector at the bottom. Once installed, the holes are then backfilled with a thermally conductive soil (typically bentonite).
In winter, water circulating inside a sealed loop absorbs heat from the earth and carries it to the unit. Here it is compressed to a higher temperature and sent as warm air to the indoor system for distribution throughout the home.
In the summer, the system reverses and expels heat from the home to the cooler earth via the loop system. This heat exchange process is not only natural, but is a truly ingenious and highly efficient way to create a comfortable climate in the home. Because the earth temperature is relatively constant, the unit provides rated output even when the outside temperature is over 100 degrees or below zero.
These systems have a much higher overall efficiency rating for both heating and cooling that thus will reduce the monthly utility costs for the life of the home. That, in addition to many of the other "green" features that are being incorporated into the newest Habitat-built homes, helps to make the home even more affordable for the new homeowner.
Habitat wishes to express its appreciation to Frank Glass and Western Water Wells, as well as Driscol Draper Electric, for their assistance and professional guidance in installing this new technology in Mason.