Background
What is GeoExchange Technology?
How Does it Work?
Is GeoExchange New?
What are the Major Benefits to the Home or Building Owner?
What are the Environmental Advantages?
How Popular is GeoExchange?
Is GeoExchange used Primarily in Homes?
Will GeoExchange Work in a Very Hot or Very Cold Climate?
Does GeoExchange Cost More?
How Long Will it Take For My System to Pay For Itself?
Background
Geothermal and GeoExchange® heating and cooling use the relatively constant temperature of the earth to heat and cool homes and businesses with 40% to 70% less energy than conventional systems. While conventional furnaces and boilers burn a fuel to generate heat, geothermal heat pumps use electricity to simply move heat from the earth into buildings, allowing much higher efficiencies.
What is GeoExchange Technology?
GeoExchange technology uses the earth's renewable energy, just below the surface, to heat or cool a home or other building, and to help provide domestic hot water. It's sometimes referred to as a geothermal heat pump, a ground source heat pump, or earth energy. No matter what you call it, GeoExchange systems are the best choice you can make for both your pocketbook and your planet. In fact, these systems are so good that the U.S. Environmental Protection Agency (EPA) has said they are, "the most energy-efficient, environmentally clean, and cost-effective space conditioning systems available today."
How Does it Work?
A few feet beneath the surface, the earth's temperature remains fairly constant year-round, ranging from 45º or so in northern latitudes to about 70ºF in the deep south. GeoExchange takes advantage of this constant temperature to provide extremely efficient heating and cooling.
In winter, a fluid circulating through pipes buried in the ground absorbs heat from the earth and carries it into the home. The GeoExchange system inside the home uses a heat pump to concentrate the earth's thermal energy and then to transfer it to the interior space for warmth.
In the summer, the process is reversed: heat is extracted from the air in the house and transferred through the heat pump to the ground loop piping. The fluid in the ground loop then carries the heat back to the earth. The only external energy needed for GeoExchange is the small amount of electricity needed to operate the heat pump, ground loop pump and distribution fan or pump.
Is GeoExchange New?
The basic technology has been around for more than 50 years, and many homeowners and businesses have been enjoying the benefits of GeoExchange for much of that time.
In recent years, though, significant improvements have been made in the materials used, installation methods, electronic control systems, and the efficiencies of the compressors, pumps and other equipment.
What are the Major Benefits to the Home or Building Owner?
Owners enjoy lower utility bills (25% to 70% lower than with conventional systems), lower maintenance, and higher levels of comfort, year-round. They also have the peace of mind of knowing they're being environmentally responsible.
Since a GeoExchange system burns no fossil fuel on-site to produce heat, it generates far fewer greenhouse gas emissions than a conventional furnace, and completely eliminates a potential source of poisonous carbon monoxide within the home or building. Even factoring in its share of the emissions from the power plant that produces electricity to operate the GeoExchange system, total emissions are far lower than for conventional systems.
What are the Environmental Advantages?
According to data supplied by the U.S. Department of Energy (DOE) Office of Geothermal Technologies, nearly 40% of all U.S. emissions of carbon dioxide (CO2) are the result of using energy to heat, cool and provide hot water for buildings. This is about the same amount of CO2 contributed by the transportation sector.
A typical 3-ton residential GeoExchange system produces an average of about one pound less Carbon Dioxide (CO2) per hour of use than a conventional system. To put that in perspective, over an average 20-year lifespan, 100,000 units of nominally sized residential GeoExchange systems will reduce greenhouse gas emissions by almost 1.1 million metric tons of carbon equivalents. That would be the equivalent of converting about 58,700 cars to zero-emission vehicles, or planting more than 120,000 acres of trees.
And the waste heat removed from the home's interior during the cooling season can be used to provide virtually free hot water-resulting in a total savings in hot water costs of about 30% annually, and lowering emissions even further.
How Popular is GeoExchange?
There are more than one million installations in the United States today. Although this is a very small percentage of the total HVAC market, the number of people who are choosing to install GeoExchange is growing rapidly as more learn about the technology.
Is GeoExchange used Primarily in Homes?
While many homes have been fitted with GeoExchange systems, a large number of commercial enterprises, including factories, retail stores, office buildings and schools also use GeoExchange to save energy and protect the environment. In fact, there are more than one million installations in the United States today.
According to the U.S. Environmental Protection Agency (EPA), schools are a particularly attractive place for the use of technology. Across the country, schools using GeoExchange right now are saving an estimated $25,000,000 in energy costs-which can be used instead for better educational equipment and more teachers. These schools also save a half-billion pounds of Carbon Dioxide (CO2) emissions per year.
Should all of the nation's schools convert to GeoExchange, the EPA has estimated that we could reduce oil imports by 61 million barrels annually, and provide the same environmental benefits as planting 8 million acres of trees or converting nearly 4 million cars to zero-emission vehicles. If the same comparison were made across all commercial and residential segments, the potential for environmental benefit would be staggering.
Will GeoExchange Work in a Very Hot or Very Cold Climate?
Yes, GeoExchange technology can be used in any part of the country. Why? Because it transfers heat to and from the earth, which remains at a relatively constant temperature, rather than the air, where temperatures can vary greatly.
Does GeoExchange Cost More?
Not necessarily. It depends on how you measure cost. While they sometimes cost more to install in homes than conventional systems because of the ground loop piping, GeoExchange systems typically have the lowest life-cycle cost of any heating and cooling system. Heating and cooling costs for a typical 2,000-sq.-ft. home can run as low as $1 a day.
Moreover, installation costs have declined substantially in recent years, and they're expected to continue to fall, as more builders and contractors offer GeoExchange systems, and as the industry develops innovative ways to install the systems faster and more efficiently. Altogether, GeoExchange systems are a sound investment. The amount they save the homeowner every month in energy costs is more than enough to offset their higher installation cost. Remember, too, that GeoExchange means extra savings on repair, maintenance, and hot water bills.
Furthermore, the energy efficiency of the system adds value to the home. The National Association of Realtors Appraisal Journal estimated that a home's value increases by $10 to $25 for every $1 reduction in utility bills. That's a lot of equity to build just by choosing GeoExchange!
How Long Will it Take For My System to Pay For Itself?
The answer to this question depends on what it would have cost you if you were operating another heating and cooling system, and how much lower your bills will be when you're using the GeoExchange system. You should ask your contractor to give you an estimated life cycle cost analysis, which should tell you about how much it will cost you to operate the system and how long it will take for the savings to cover the cost of the system completely.
Source: Geothermal Heat Pump Consortium