Geothermal FAQ

What is a ground source heat pump?

Ground source heat pumps (GSHPs) are electrically powered systems that use energy from the sun and collected using the greatest solar collector in existence: our earth. Using the earth's relatively constant temperature a geothermal system can provide heating, cooling, and hot water for homes and commercial buildings.

How do ground source heat pumps work?

Ground source heat pumps get their energy from one of two types of loops; closed loop or open loops. Closed 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. Your local installer can review your site and help recommend the system that best matches your application.

How do you get heat out of 50 degree ground water?

You have a heat pump in your house right now! Your refrigerator takes heat out of the food and releases the heat to the outside. (Feel how warm it is behind your refrigerator.) A heat pump works in much the same way. It removes heat from the water that is circulated through the loop field and concentrates it before releasing it into your home.

How much does it cost?

Of course, the costs vary depending on the size and complexity of the system you choose. Generally speaking, a geothermal system will be more expensive than a conventional system up front, but its low operating costs more than offset the initial expense.

Just how efficient are these systems?

Here is where geo systems excel! While gas furnaces compete with each other over 92% or 96% efficiencies, geo systems are upwards of 300% efficiencies. That's not bragging. That is ARI certified test data.

How can any system be more than 100% efficient?

Geothermal systems don't make heat: they simply move it from the earth into your home. In essence, you are just paying for the transportation. In fact, for every BTU of energy you use, you will get back 3 BTU's of heat making geothermal heating 300% efficient!

Are Geothermal Systems Safe?

They are the safest heating system you can put in your home. They use no combustion gasses or fossil fuels of any kind nor do they produce carbon monoxide or carbon dioxide. There is no risk of explosion since there is no flame at all!

What about the environmental impact of removing heat from the earth?

The EPA has called geothermal heat systems the "most environmentally friendly system you can put in your home". They burn no fuel and therefore, they produce no byproducts. The little heat that is borrowed from the earth over the winter is put back in the summer making the cycle complete.

Is a ground source heat pump worth the extra initial cost?

Almost always, yes. Let's look at an example of a 1700 sq ft house and compare the cost of operation of a TTHERM GEO ™ heat pump using a heat pump rate of $.05/Kwh with a 92% efficient LP furnace using $1.25/gal fuel prices. Assume the heat pump costs $15,000 installed and the furnace and A/C costs $6000 (not counting ductwork in either case). Assume also that your electric rate is increasing by 2%/year and LP is going up 5%/year and you finance your house for 20 years at 6% interest. The annual cost of operation of the heat pump combined with loan costs is $1927 ($1289 loan cost and $638 operating cost) and the annual cost of the conventional system is $2609 ($515 loan cost and $2054 operating cost). You save $647 your first year of operation. After 10 years, you save $11,231: More than enough to pay back the difference in cost. The bigger the house, the more you save.

Are Geothermal units difficult to install?

Most units are easy to install, especially when they are replacing another forced-air system. This is known as a retrofit. Geothermal units can be installed in areas unsuitable for fossil fuel furnaces because there is no combustion and thus no need to vent exhaust fumes. Ductwork must be installed in homes without an existing air distribution system. Your dealer or installer can assess the cost of installing ductwork.

What about comfort?

A Geothermal unit system moves warm air (90-105(F) throughout your home or business via standard ductwork. 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.

Do Utility companies offer rebates on ground source heat pumps?

Many of them do but the purchase of a ground source heat pump should make sense without rebates. If they offer rebates, that is the icing on the cake but the real value is in your monthly savings on your energy bill. Contact your local utility company for their rebate program.

How does geothermal compare with other renewable energy technologies?

A geothermal system will give you the quickest return on investment of any form of renewable energy. Often, the price difference between a conventional heating system and a geothermal system can be paid back in 5-7 years. In fact, the savings realized on your energy bills from your geothermal system can be used to finance additional renewable energy technologies for your home if you choose.