FAQ
A GSHP system can be installed in a residential structure of any size, anywhere, whether it is single-family or multi-family. GSHPs can be installed on almost any size lot: under lawns, landscaped areas, or driveways. An existing house can be retrofitted with a GSHP using the duct work that is already there. Your dealer/installer will be able to determine duct work requirements and if any minor modifications are needed. Home builders and homeowners can both take advantage of the special financing that is offered in many locations on a GSHP either through the utility or manufacturer.
The Department of Energy (DOE) and the Environmental Protection Agency (EPA) have both endorsed ground source heat pump systems as among the most energy efficient and environmentally friendly heating, cooling, and water heating systems available. In a 1993 report, the EPA concluded that geothermal technologies represent a major opportunity for reducing national energy use and pollution, while delivering comfort, reliability and savings to homeowners.
What is a ground source heat pump?
Ground source heat pumps (GSHPs) are electrically powered systems that tap the stored energy of the greatest solar collector in existence: the earth. These systems use the earth’s relatively constant temperature to provide heating, cooling, and hot water for homes and commercial buildings.
How do ground source heat pumps work?
Ground source heat pumps can be categorized as having closed or open loops, and those loops can be installed in three ways: horizontally, vertically, or in a pond/lake. The type chosen depends on the available land areas and the soil and rock type at the installation site. These factors will help determine the most economical choice for installation of the ground loop.
For closed loop systems, water or antifreeze solution is circulated through plastic pipes buried beneath the earth’s surface. During the winter, the fluid collects heat from the earth and carries it through the system and into the building. During the summer, the system reverses itself to cool the building by pulling heat from the building, carrying it through the system and placing it in the ground. This process creates free hot water in the summer and delivers substantial hot water savings in the winter.
Open loop systems operate on the same principle as closed loop systems and can be installed where an adequate supply of suitable water is available and open discharge is feasible. Benefits similar to the closed loop system are obtained.
How efficient is a GSHP?
The GSHP is one of the most efficient residential heating and cooling systems available today, with heating efficiencies 50 to 70% higher than other heating systems and cooling efficiencies 20 to 40% higher than available air conditioners. That directly translates into savings for you on your utility bills.
Can one system provide both space heating and cooling for my home? And what about heating hot water?
Yes. A GSHP can be a combination heating/cooling and hot water heating system. You can change from one mode to another with a simple flick on your indoor thermostat. Using a desuperheater, some GSHPs can save you up to 50% on your water-heating bill by preheating tank water.
How does a GSHP system heat water for my home?
Using what is called a desuperheater, GSHPs turn waste heat to the task of heating hot water. During the summer, when the system is in cooling mode, your hot water is produced free as a byproduct of the thermal process. In winter, with the heating mode, the desuperheater heats a portion of your hot water. Desuperheaters are standard on some units, optional on others. Stand-alone systems that will heat water all year around can be purchased.
How much space does a GSHP unit require?
Most of a GSHP installation is underground. Inside the house, the heat pump units are about the same size as a traditional heating and cooling unit.
How long will my GSHP system last?
GSHPs are durable and highly reliable. The GSHP contains fewer mechanical components, and all components are either buried in the ground or located inside the home, which protects them from outside conditions. The underground pipe carries up to a 50-year warranty.
How noisy is the GSHP unit?
GSHPs are very quiet, providing a pleasant environment inside & outside of the home. GSHPs have no noisy fan units to disturb outdoor activities, on or near the patio.
How safe are GSHPs?
GSHP systems are safe and protected. With no exposed equipment outdoors, children or pets cannot injure themselves or damage exterior units. GSHPs have no open flame, flammable fuel or potentially dangerous fuel storage tanks.
What about comfort?
A GSHP system moves warm air 90-105(F) throughout your home or business via standard duct work. An even comfort level is created because the warm air is moved in slightly higher volumes and saturates the building with warmth more evenly. This helps even out hot or colds spots and eliminates the cold air blasts common with fossil fuel furnaces.
How effective is this underground system?
The buried pipe, or ground loop, is the most recent technical advancement in heat pump technology. Recently, new heat pump designs and improved buried pipe materials have been combined to make GSHP systems the most efficient heating and cooling systems available.
How will I save money with a GSHP?
GSHPs save money, both in operating costs and maintenance costs. Investments can be recouped in as little as three years. There is a positive cash flow, since the energy savings usually exceeds payment on the system.
How much does a GSHP cost?
The initial investment for a GSHP system is greater than that of a conventional system. However, when you consider the operating costs of a geothermal heating, cooling, and water heating system, energy savings quickly offset the initial difference in purchase price.
What other costs are there besides the GSHP system?
You can expect an installation charge for any electrical work, duct work, water hook-up, and other provisions or adaptations to your home that are required. Your installer can estimate these costs in advance.
Does my state offer any incentives for installing a GSHP system?
Some utilities offer rebates or incentives to their customers who purchase GSHPs. To see what your state has to offer click here.
How do GSHPs protect the environment?
GSHP systems conserve natural resources by providing climate control very efficiently-thus also lowering emissions. GSHPs also minimize ozone layer destruction by using factory-sealed refrigeration systems, which will seldom or never have to be recharged.
What are the environmental benefits of GSHP systems?
Currently installed systems are making a huge difference in our environment! The systems are eliminating more than three million tons of carbon dioxide and is equivalent of taking 650,000 automobiles off the road. GSHP systems conserve energy and, because they move heat that already exists rather than burning something to create heat, they reduce the amount of toxic emissions in the atmosphere. They use renewable energy from the sun, and because the system doesn’t rely on outside air, it keeps the air inside of buildings cleaner and free from pollens, outdoor pollutants, mold spores, and other allergens.
Do soil freezing conditions create any problems?
Not if a system is properly designed and installed. The three to four foot depths allow the sun to melt the frozen soil during the summer. Adequate length per ton capacity prevents objectionable soil movement.
Will my existing duct work function with this system?
Yes, in most cases. Your dealer or installer will be able to determine duct work requirements and if any minor modifications are needed.
Will an underground loop affect my lawn or landscape?
No. Research has shown that loops have no adverse effects on grass, trees, or shrubs. Temporary bare areas can be restored with grass seed or sod. Vertical loops require little space and do not damage lawns significantly.
My yard contains many shade trees. Will this affect ground temperature and my ability to use it as an energy source?
Not at all. The system is installed deep enough that it utilizes constant ground temperature.
Can a GSHP system be added to my fossil fuel furnace?
Yes. Called dual systems, they can easily be added to existing furnaces for those wishing to have a dual-fuel heating system. Dual-fuel systems use the GSHP system as the main heating source, and a fossil fuel furnace as a supplement in extremely cold weather should additional heat be needed.
Will I have to add insulation to my home if I install one of these systems?
Ground source heat pump systems will reduce your heating and cooling costs regardless of how well your home is insulated. However, insulating and weatherizing are key factors in gaining the maximum amount of savings from any type of heating and cooling system.
Copyright© 2006 IGSHPA/OSU.
