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RELM Services in Texas is happy to provide you more information about geothermal systems.

Discover the answers to some of our most frequently asked questions:

What is Geothermal?

Geothermal heating, also referred to as green heat, geoexchange, geothermal heat pumps (GHPs), ground-source heat pumps (GSHPs) and water source heat pumps, is one of the most efficient ways to heat and cool a home. Everyday more homeowners are discovering the benefits of these systems, which tap the relatively constant temperature of the Earth.

During the winter, a geothermal heat pump uses underground piping, known as an “earth loop” to extract heat from the ground. As the system pulls heat from the loop it distributes it through a conventional duct system as warm air. The same heat energy can also be used for a radiant floor system or domestic hot water heating. In Texas, the earth stays at a relatively constant temperature of approximately
58-68 degrees.  

Essentially the opposite occurs during the summer when the geothermal heat pump absorbs heat from the air in your home and transfers it to water circulating in the earth loop where it is absorbed by the earth. This provides cool, dehumidified and comfortable air throughout your home.

Energy and cost savings of geothermal heat pumps will vary by region and type of conventional that they are compared with but the energy cost of geothermal versus conventional HVAC systems will always be lower - and the geothermal system will always be a greener option.

What are the major benefits to installing geothermal?

The biggest benefit of geothermal is that it uses 25% to 50% less electricity than conventional heating or cooling systems. This translates into a geothermal heat pump using one unit of electricity to move three units of heat from the earth and saving 25% to 70% on utility bill. According to the EPA, geothermal heat pumps can reduce energy consumption and corresponding emissions up to 44% compared to air-source heat pumps and up to 72% compared to electric resistance heating with standard air-conditioning equipment. Geothermal heat pumps also improve humidity control by maintaining about 50% relative indoor humidity, making geothermal very effective in humid areas.

What are the environmental advantages of geothermal?

According to 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.

Currently installed systems are making a huge difference in our environment! Geothermal systems are eliminating more than three million tons of carbon dioxide and are equivalent of taking 650,000 automobiles off the road. Geothermal systems conserve energy and because they move heat that already exists rather than burning something to create heat, thereby reducing the amount of toxic emissions in the atmosphere. They use renewable energy from the sun and because the systems don't rely on outside air, they keep the air inside of buildings cleaner and free from pollens, outdoor pollutants, mold spores and other allergens.

How much will a geothermal system cost to install?

The costs associated with installation have a wide range based on a number of factors, such as the structure's size and design, type of construction, location, etc. so it is impossible to provide a number here. However, with federal and state tax incentives as well as the amount geothermal saves the owner every month in costs, it is more than enough to offset the higher installation cost.

How long will the system take to pay for itself?

This answer is based on what it would cost for you to operate another heating and cooling system as compared to how much your bills will be lowered operating a geothermal system. An energy analysis can show the cost of operating a geothermal system as compared to a conventional system and how long it will take for the savings to cover the cost of the system completely. Natural gas users typically see a payback of approximately 5 to 10 years and propane gas users see it as quickly as 2 to 5 years. It is lesser with oil.

What size system will I need?

It is recommended that if you are strongly considering going with a geothermal system, you should have a heat load calculation done on your home. This gives the information needed to properly size your geothermal system and give you the most efficient system to meet your needs.

What is a hybrid system?

Technically a hybrid system is a system that can use more than one power source. In our case, it is a backup heating unit (Gas, LP, or Oil furnace) with another high efficient heating / cooling system. This would be a high tech heat pump. This heat pump can act as an air conditioner in the summer to keep you cool. In the winter, the heat pump can work in "reverse" taking the free heat from the outside and concentrating it to heat your house.

The only cost to get this heat a small amount of electricity to run the compressor (outside unit) and the blower motor. With the new efficiencies available it can be cheaper to heat your house in temperatures down to 10 degrees than with a high efficient furnace. Adding a backup furnace with a DC motor can lower
costs more.

How long do geothermal heat pumps last?

Geothermal heat pumps are durable and require little maintenance. They have fewer mechanical components than standard systems and most of those components are underground or indoors, sheltered from the weather.

The underground piping used in the system is often guaranteed to last up to 50 years and is virtually worry-free. The components inside the house are small and easily accessible for maintenance. Warm or cool air is distributed through ductwork, just as in a standard forced-air system.

How much indoor space does a geothermal heat pump occupy?

Most of the installation is underground and the surrounding landscape will dictate what loop system is the best fit for the available space. Inside the home, the geothermal heat pump is similar in size to a traditional heating and cooling unit.

Which system is best for me, open-loop or closed-loop?

The net results in operating cost and efficiency are virtually the same. The best system for you will depend on whether you have an adequate groundwater supply and means of disposal. If you do, an open-loop can be used. If not, a closed-loop system is the best option. A trained technician can help you decide which system is the best for your location.

What is the environmental impact of installing a geothermal heat pump in my home?

According to data supplied by the U.S. Department of Energy, a typical 3 ton residential geothermal heat pump system produces an average of about one pound less carbon dioxide (CO2) per hour of use than a conventional system. For perspective, this would have an environmental equivalent of reducing emissions from one automobile over that same time period by nearly 60% or planting 12 acres of trees annually!

Will an underground loop affect my lawn and surrounding landscape?

No. Research has shown that loops have no adverse effect on grass, trees or shrubs. Most horizontal installations require trenches 5 feet–6 feet deep and 3 feet wide depending on the system size. Temporary bare areas and problematic regions of the landscape can be restored with grass seed or sod. In some instances trenching provides an opportunity to remove and repair low lying landscape and areas with poor drainage. Vertical loops require little space and will not damage lawns significantly. In either case, expect the need for post installation landscaping.

Will I need an additional heat source during extremely cold weather?

All systems require emergency backup heat if they are the only heating source for the home. Geothermal heat pumps are able to provide all the necessary heat in the coldest weather. An analysis can dictate what portion of heat is provided by the heat pump and what portion would be by auxiliary means.

Can a geothermal heat pump also provide hot water for my home?

Yes. Using a Hot Water Generator (HWG) for on-demand hot water or desuperheaters to supplement the production of domestic hot water.

Will I have to add insulation to my home if I install a geothermal heat pump?

Geothermal heat pumps will reduce your heating and cooling costs regardless of how well your home is insulated, however to maximize savings, insulation and weatherization are key factors for any type of heating and cooling system.

How much does a system like this cost?

In most circumstances, the initial investment for a geothermal heat pump is greater than a conventional system, but over time the energy savings quickly offsets the initial difference in purchase price. To get an accurate comparison, you would need to consider the following:

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Energy costs and availability – Fossil fuel markets can see price fluctuations which should be taken
into account.

Energy efficiency and ratings of the existing system vs. a geothermal heat pump – This can be affected by how well your home is insulated.

Payback – How long it takes to recover the difference in installation costs between the two systems using comparative energy savings. This usually runs 3-5 years, but will depend on the scope of work.

Total operating savings from heating, cooling, and domestic hot water – Which is typically lower with geothermal heat pumps.

Find Out More

Find out the meanings of common geothermal terms.