An earth-coupled HVAC system is packed with environmentally-friendly benefits, especially when compared with other types of heating and cooling systems. As heating and cooling systems go, a ground sourced system comes closest to the way Mother Nature would heat and cool a building if given the opportunity.
Geothermal is a fundamentally solar powered technology. The earth absorbs 50 percent of the solar energy that reaches our planet, and that energy tends to stay near the surface where it is accessible through the installation of a geothermal exchanger. That’s because with ground coupling, the building becomes coupled with the Earth beneath, sharing that temperature with the building’s ground source heat pumps (GSHPs), similar to the way the roots of trees share nutrients with their branches and leaves. Take a look at some of the environmental benefits you can enjoy with geothermal system.
- Reduction in use of chemical refrigerants (geothermal usually has no refrigerant lines to the outside, just closed loop water pipes underground).
- Elimination of combustion-related heating in the home (earth is the energy source; the sun replenishes warmth seasonally and continually, providing a truly renewable heating source). Fundamentally, geothermal heating is no different than solar heating. Earth is the great big solar collector, and we can tap into that heat all year long (with or without solar collectors). A better answer!
- Enabling the use of waste heat from the compressor for domestic hot water, instead of exhausting it to outside air in the summertime, further reducing environmental impacts relating to combustion or electric heating of domestic water.
- Reduced electrical consumption compared other heating and cooling systems, resulting in fewer emissions from power plants.
- Reduced noise pollution from outside equipment cycling noises and distractions.
A ground source heat pump does not create heat by combustion (flames) or from electrical resistance like a blow dryer. Just as the name denotes, it is a “pump” that moves “heat.” In this scenario, it is from the ground. That’s why we call it “ground-source” and alternatively “geothermal.”
The compressor in the heat pump takes the temperature collected from the earth beneath, and pumps it to a higher temperature for delivery through duct work or radiant piping into the building. The heat pump uses 1 unit of heat-pump power to deliver 5 units of usable heat to the building. The technical rating for this is “Coefficient of Performance” or “COP”. That means a GSHP can be 500 percent efficient, delivering 5 times the energy it consumes, or in other words, it’s rated at a “5-COP.” The illustration makes it a little easier to understand.
The United States Environmental Protection Agency says, “Ground source heating and cooling can be done almost anywhere in the United States using a geothermal heat pump, a highly efficient renewable energy technology that takes advantage of the constant temperature of the earth beneath the surface. The heat pump transfers heat stored in the Earth or in ground water into a building during the winter, and transfers it out of the building and back into the ground during the summer. In other words, the ground acts as a heat source in winter and a heat sink in summer. Applications of this technology are for space heating and cooling and hot water.”
How would you like to get on the geothermal bandwagon? The geothermal industry is getting behind an effort toward “Geothermal Day 2015.” Visit the Geothermal Day website and sign up as a supporter; you’ll be glad you did! (Use the #GeoDay2015 hashtag on your social media.)