Geothermal energy represents the leading edge of heating and cooling technology. It’s safe, reliable and the most energy efficient system available, since it moves heat energy to and from the earth to heat and cool your indoor environment. Compared to ordinary systems (oil, gas, propane, electric), geothermal technology can save you 30 to 60 percent on your monthly energy bills. Geothermal is the cleanest, most reliable heating and cooling system you can buy.
The universal definition of geothermal is “…pertaining to the heat of the earth.”
The amazing thing about geothermal energy is that it’s an unlimited resource, unlike other forms of energy in use today. In fact, the lot surrounding a suburban home or other building contains a vast reservoir of low temperature thermal energy, typically 10 times that which is required over an entire heating season. This resource is constantly resupplied by the sun, the surrounding earth and heat rejected while cooling during the summer. By using the earth to provide up to 50 percent of a building’s total heating and cooling needs, these systems are truly geothermal energy made practical.
Another plus for geothermal systems is that only one unit is necessary, versus a heating unit and a cooling unit as with other systems. The units are quiet and many offer two stages, which means the unit doesn’t run at full capacity unless absolutely necessary. The units use electricity of operate, not to heat or cool, but to run the components that transfer heat to and from the ground. According to Darwin Burtener of Western Pennsylvania Geothermal Heating and Cooling, Inc., “For every dollar spent on electric to run a small pump, compressor and fan, you get $4 free from the ground. Geothermal helps us as a country to be less dependent on other resources, domestic and foreign, and our power generation plants to be more efficient.”
There are four types of installations: three that are “closed loop” and one “open loop.” Systems can be installed horizontally or vertically, depending upon the site and space available. A short description of each is below. I also encourage you to watch the included video, which goes into more detail about the system installation.
Closed Loop Designs
Horizontal Loop
Horizontal loops are often considered when adequate land surface is available. Pipes are placed in trenches, in lengths that range from 100 to 400 feet.
Vertical Loop
Vertical loops are the ideal choice when available land surface is limited. Drilling equipment is used to bore small-diameter holes from 75 to 300 feet deep.
Pond or Lake Loop
Pond (lake) loops are very economical to install when a body of water is available, because excavation costs are virtually eliminated. Coils of pipe are simply placed on the bottom of the pond or lake.
In a closed loop design, piping is installed vertically in 50-250 foot deep holes drilled like a well, or horizontally in 3-6 foot deep trenches. The piping doesn’t require above ground access making it the ideal system to install under driveways, landscaping and parking lots.
Open Loop Design:
Open Loop Design
Open loop systems utilize ground water as a direct energy source.
Open loop systems work similarly to closed loop; a constant source of ground water is circulated, but instead of it staying within the loop, the water is dispelled back to its origin, such as an aquifer, stream, well or pond. While these systems are lower cost to install, they are not commonly used because of the special installation requirements.
Geoexchange Video about Geothermal Heating and Cooling
Unlike conventional units, installation varies by the needs of the structure, the surrounding area and the type of system desired. Additionally, not all sites are appropriate for a geothermal system. Because each installation is unique and site acceptability so critical, you’ll want to use an experienced installer, preferably one who also designs systems.
Once the system is installed, the heated or cooled air is delivered throughout the structure in a manner similar to traditional forced air systems. Heating offers another alternative – radiant heat – whereby coils are placed under flooring allowing the heat to rise up into the room from the lowest point. I lived in a house with radiant heat years ago. I loved having warm tile floors – especially in the middle of the night.
Here’s the icing on the cake: these systems can also provide hot water at significantly reduced cost. If you’ve ever lived with teenagers who take hour-long, scalding hot showers, you’ll appreciate this perk even more.
If there’s a downside to geothermal heating and cooling it’s this: cost. A typical system can cost 20 to 30 percent more to install than conventional systems. But if you consider the annual energy savings you’ll enjoy with your geothermal system, it’s likely you will pay off your system in a few short years. To add an incentive, the government has stepped in to provide relief to consumers willing to take the “geothermal plunge” by offering a 30 percent tax credit. That’s certainly nothing to sneeze at.
The key to a successful transition to geothermal heating and cooling lies with the contractor. While this technology has been around for decades, most traditional HVAC companies haven’t made the switch to geothermal. Given the renewed interest in “green living” and the concern regarding foreign energy sources, geothermal systems are gaining in popularity. Consequently, more HVAC companies are getting into the geothermal business.
It’s incumbent upon the home owner, builder or general contractor to be sure the company selected has the experience to not only do a quality installation, but back up their work. That’s why Western Pennsylvania Geothermal Heating and Cooling has an edge. They’ve been designing and installing these systems for years. They have the know-how and experience to back up their work and provide peace-of-mind to the home or building owner.
So, is a geothermal system in your future? If you love your home and plan to stay in it for many years, or if you’ve always wanted to build a new home with an eye toward energy efficiency and “green” standards, then consider including a geothermal system. What have you got lose – except high energy bills?
Want to learn more?
- Energy Star Information on Geothermal Heat Pumps
- Geoexchange
- Finger Lakes Institute PDF on Geothermal Systems
{ 2 comments… read them below or add one }
I understand that geothermal technology cuts down on cost and energy waste. But, what about the consumption of water. Is this something to raise a cause for concern?
Great question. I believe that the water consumption is minimal, since most of the systems used are closed-loop. This means (as I understand it) the water that was put in originally is what circulates for as long as the system is functioning. In an open loop system, water use could be of concern, since it’s dependent upon a ground water source. Perhaps it’s this requirement that makes open loop systems less prevalent. Thanks so much for reading and for commenting!