Heating systems that use natural gas or oil are relatively efficient, but will consume a great deal of your annual budget and will negatively impact the environment in the form of greenhouse gas and related pollution. For Illinois homeowners in Northbrook, Glenview, and Deerfield who want exceptionally efficient home heating that’s also environmentally friendly, geothermal heating systems offer a powerful combination of performance factors that make them one of the best home comfort options available.
The following brief overview of geothermal heating systems will explain how geothermal heating works and why it’s such an outstanding choice.
The Function of Geothermal Heating Systems
Geothermal heating uses a heat pump that functions by capturing heat and moving it around, taking it out of your home to provide indoor cooling and bringing it inside to provide heating. Unlike air-source heat pumps that use the air around the unit as a medium for heat capture and dispersal, geothermal models pull heat out of and release heat into the ground outside your home.
There are two sets of components to geothermal heating systems, one installed indoors and the other outdoors. The indoor components consist of the heat pump itself, along with heat exchangers and air distribution fans. The outdoor components are a lengthy series of pipes, called a loop, that’s buried about six to 10 feet underground. At that depth, the temperature of the soil surrounding the loop pipes stays about 45 to 75 degrees throughout the year. This relatively consistent temperature provides a reliable and stable environment for heat capture and release. The loop pipes contain water or a water/antifreeze mixture that can easily absorb or give off heat.
During home heating functions, the liquid in the outdoor loop absorbs heat from the soil surrounding the pipes. The liquid circulates to the indoor components where heat exchangers transfer heat and warm up the air that will be used to heat your home. The warmed air is forced into the ductwork by the air handling fans. When the air exits from vents in your home, it provides the indoor comfort you expect from your HVAC system.
Geothermal heat pumps provide cooling as well. During these operations, the flow of the liquid in the loop pipes is reversed. Heat is acquired from inside your home, which produces cooling, and is released into the ground around the outside loop pipes.
Efficiency and Economics of Geothermal
Perhaps the most attractive and beneficial feature of geothermal heating systems is their extremely high levels of efficiency, which translates into substantial savings on monthly home heating expenses.
Geothermal equipment uses electricity to capture heat and move it from place to place. In general, they will use substantially less electricity to provide heating than more traditional heating systems. They typically use up to 50 percent less electricity to provide heating than other conventional sources. Their energy consumption for producing heating is often more than 40 percent less than that of an air-source heat pump and more than 70 percent less than that of electric resistance heating.
Geothermal systems can usually move three or four units of heat for each unit of electricity consumed. This results in an extremely high level of efficiency of 300 to 400 percent. This exceptional efficiency translates into substantially reduced costs for heating, easily slashing monthly bills by 50 percent or more.
Homeowners will frequently find that the increased monthly savings offered by geothermal heating will allow them to recover the cost of the equipment and its installation within a relatively short time. Costs have been recouped in as little as two years, but more commonly, a geothermal heating system pays for itself in monthly savings alone by about the halfway point of the system’s expected functional life or about 10 years.
Another element of geothermal economics that benefit homeowners is the tax credits and other incentives offered by federal, state and local sources. For example, the U.S. government offers a tax credit of 30 percent of the cost of geothermal equipment and installation for systems installed before December 31, 2016. There’s currently no upper limit on the total amount of the credit. Certain state and local organizations may also provide renewable energy incentives or other financial benefits for those who install geothermal heating systems.
Other Benefits of Geothermal Heating Systems
Beyond the undeniable benefits of high efficiency and economical operation, geothermal heating systems offer homeowners other appealing benefits.
- Longer expected life span: Geothermal equipment can be expected to last up to 20 years or more, with greater life spans probable for equipment that has been well maintained. Loop pipes are typically guaranteed for up to 50 years.
- Reduced environmental emissions: In addition to reducing energy consumption, geothermal heating systems also reduce environmental emissions, greenhouse gases and pollution. They don’t burn fossil fuels themselves, which means the equipment in your house doesn’t produce emissions or dangerous combustion by-products such as carbon monoxide (CO). Geothermal cuts overall emission rates by 40 to 70 percent.
- Quiet operation: Geothermal systems function quietly. They’re so quiet that owners have reported not even being aware of when the equipment is operating.
- Flexibility of installation: Geothermal heat pumps are appropriate for any climate in any area of the country. They can be installed in urban, suburban or rural environments. The equipment is smaller than other types of HVAC equipment, saving space inside your home. Geothermal systems can be used with equal ease in new construction projects or in retrofits and renovations.
- Better humidity control: Geothermal heating systems provide better indoor humidity control. They can easily keep indoor relative humidity levels at about 50 percent, which is within the ideal zone for indoor humidity.
- Water heating savings: If your geothermal system is equipped with a desuperheater, it can divert a portion of the heat it moves around to heating water for home use. This can also significantly reduce a major energy expense. In the summer, heat pulled out of your home heats water for nothing; in the winter, heat brought in from the ground outside can cut water heating expenses by 30 percent or more.
Land Evaluation for Geothermal
If you’re thinking about having a geothermal system installed for your home, remember that it takes more preparation and evaluation than the relatively simple installation of a furnace or air-source heat pump. Land evaluation is one of the major tasks that will have to be performed before geothermal heating systems are put in.
- Available land: Geothermal heating systems require a certain amount of available land for installation of the loop pipes. Before installing a geothermal system, you must be certain you have enough land for the installation. Horizontal installations are the most common and will require a large area of land for the loop. If the amount of land you have is minimal, you may still be able to use a geothermal system with a vertical installation. Vertical installations place the loop pipes in hole drilled into the ground to a depth of 100 to 400 feet.
- Geology: The geology of the available land will also affect the type of installation that can be performed. Horizontal loop installations are common when there’s plenty of soil for burying the loops. However, a vertical installation could be used if topsoil depth is shallow or the ground around your home is rocky. A geological evaluation will also determine if there are beneficial characteristics of the soil around your home. If the soil can more easily conduct heat, for example, a smaller arrangement of loop pipes could be used, reducing installation costs.
- Hydrology: If there’s groundwater a short distance under the surface of the ground, it could affect the installation of a geothermal loop system. You must also be sure that your geothermal installation doesn’t contaminate or pollute any underground water sources such as aquifers. A hydrological evaluation can tell you if you would be better off switching to a water-source geothermal installation that uses a body of water instead of soil for heat capture and release.
Installation of Geothermal Heating Systems
The performance of your geothermal heating system and the safe operation of the equipment can be significantly affected by the quality of the installation.
- Make sure you choose a licensed and knowledgeable installer, preferably a geothermal installation specialist.
- Check references and licensing information.
- Get a detailed contract and make sure both you and the contractor approve and sign it.
- Ask questions about the process until you’re satisfied with the answers you get. Don’t proceed until you understand what will happen and what will be required of you and the contractor.
With more than 35 years of experience in the heating and air conditioning industry, Roberts Heating & Air Conditioning is a premier provider of HVAC sales, installation, maintenance and repair in Northbrook, Deerfield, Glenview and neighboring northern Illinois communities. Contact us today for more information on geothermal heating systems and their many benefits in efficiency, performance and monetary savings.
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