When it comes to efficiency, it doesn't get much better than a geothermal
heat pump (GHP). We've already discussed the efficiency benefits of
heat pumps in a previous post, as well as the added benefits of geothermal systems.
If you're interested in installing a geothermal heat pump on your property,
read on for a step-by-step guide to the process.
Geothermal Heat Pump Basics
In case you're unfamiliar with the basic tenants of geothermal heating
and cooling, here is a quick explanation of how it all works.
Shallow ground temperatures are more or less consistent throughout the
Continental United States, and geothermal heat pumps can utilize those
constant temperatures to regular the climate of your home.
The benefits of this type of system are enormous. Although there is a higher
cost of installation relative to other methods of heating and cooling,
geothermal systems can save 40 to 80% in long-term energy costs.
Check out this video from the U.S. Department of Energy to learn even more
about geothermal heat pump systems.
Assessing Your Property
Before you dive into the buying process, it's important to evaluate
your property to be sure it can accommodate a geothermal system.
Have your local specialist investigate the geology and hydrology of your
property to determine what type of geothermal system, if any at all, is suitable.
Choosing a System
Although geothermal heat pumps make up a very specific niche in the
HVAC industry, there are still plenty of choices. However, your decision will
be dependent on your property.
The three major types of geothermal systems are outlined below. For more
information on each type of system, visit
Closed-loop systems. Closed-loop systems utiliz a length of tubing, usually plastic, which is
circulated with antifreeze and coiled deep underground. A special device
called a heat exchanger conducts the heat derived from the loop to the
refrigerant in the above-ground unit, which then regulates the temperature
of your home. Closed-loop systems can be installed in several configurations
– horizontal, vertical, or in a pond or lake.
Open-loop systems. Open-loop systems utilize surface body or well water to regulate temperature
rather than antifreeze. The water is circulated through the system, run
through an exchanger the same as in a closed-loop system, and then discharged
in a separate well.
Hybrid systems. Hybrid systems that utilize a combination of geothermal resources are also
available. Since these systems vary from installation to installation,
there is no standardized description.
SEER, EER, and COP Ratings
While shopping for a geothermal unit, you're likely to see several
efficiency ratings that aren't familiar to the average joe –
SEER, EER, and COP. Thankfully, these ratings are pretty simple to understand
once you learn the basics.
The SEER rating (Seasonal Energy Efficiency Ratio) represents the ratio
of a unit's cooling power to the amount of electricity it burns through.
In simple terms, the higher the SEER rating, the more efficient the unit.
During your shopping experience, you'll probably see units that are
rated with EER and COP instead of a single SEER rating. Don't let
those measurements scare you! Although the details of how EER and COP
are calculated are beyond the scope of this article (Don't worry.
You won't need to calculate those ratings on your own. The manufacturer
will always provide them), you can easily use them to figure out the SEER
of any given unit.
If all you're given is an EER and COP rating, simply divide the EER
by the COP to get the SEER.
Installing the System
Geothermal heat pump installation is by no means a do-it-yourself project.
The advanced knowledge and equipment required to install a geothermal
system are far beyond that of even the most avid DIY-er.
To find a suitable installer for your system, get in touch with the
International Ground Source Heat Pump Association, your local utility provider, or the
Geothermal Heat Pump Consortium. Any of these three resources will be able to help you find the perfect
people for the job.
Use this guide in conjunction with the assistance of your local geothermal
specialist to find the perfect system for your home. Feel free to
contact Tom's Mechanical, Inc. in Arlington, Texas for more information.
1. Photos via
2. Photo via