Is Geothermal All It’s Cracked Up To Be?October 6, 2013
In the ongoing quest to come up with viable energy alternatives for heating and cooling our homes, every new energy source out there has its share of fans and detractors. Geothermal HVAC (Heating, Air Condition, Ventilation) has been maligned as a noisy, inefficient, water-wasting, space-hogging waste of time. But is it really?
Geothermal HVAC Defined
First of all, let’s nail down just how geothermal HVAC works. While temperatures on the Earth’s surface change according to the season, roughly four to six feet below the Earth the temperature remains constant. A geothermal HVAC system uses a loop of polyethylene pipes buried underground that use liquid to bring heat stored underground into the home in the winter, where a unit compresses it to a higher temperature and circulates it through the house. In the summer, heat is pulled from the house and into the loop, where it’s deposited in the relatively cooler earth.
The only machinery used in an HVAC system is a fan, pump, and compressor.
Exploding HVAC Myths
Geothermal HVAC has its critics, and they’ve leveled a series of objections about this particular form of heating and cooling, and have argued that other forms of alternative energy are more efficient and cost-effective. Here’s some of the biggest “charges”.
The system requires too much land for the earth loops.
The pipes can be placed either horizontally or vertically underground, thereby able to adjust to the overall square footage of the property.
HVAC uses lots of water.
These systems actually expend no water. If an aquifer is used as the heat exchange, all of that water igoes back to its original source. There is no waste.
Geothermal HVAC is not a renewable energy source because it needs electricity to power the fan and compressor.
The proportion is one unit of electricity per five units of heating or cooling. That’s efficiency!
The HVAC pumps are loud
The system is quiet, and since it’s all self-contained within and under the residence, there’s no noise to annoy the neighbors.
Geothermal HVACs can only heat, not cool
The HVAC is a year-round system, providing heat in the winter, and drawing heat out of the home in the summer.
The geothermal system cannot perform multiple functions, such as heating a house, hot water, and a pool simultaneously.
It depends on the size of the system. They can be engineered to handle bigger demands.
The system eventually wears out
The earth-loops last for whole generations, and the equipment lasts for decades, since the entire assembly is shielded from the elements, underground in the case of the pipes, and in the home in the case of the equipment. The loops would be the most expensive thing to replace and considering the amount of time that passes between replacements, it’s certainly a cost-effective means of heating and cooling.
Admittedly, some of the objections were true at one point, but advances in technology have rendered those arguments obsolete. Geothermal HVAC systems are already being used in many buildings, and are considered an extremely eco-friendly means of heating and cooling. Geothermal HVAC may very well become a major supplier of cooling and heating in the coming decades.