Unlocking Comfort and Efficiency with Ground Source Heat Pumps
Thomas W. Howard, CEO/General Manager
March 2025 Column
When we think about renewable energy, it’s natural for images of solar panels or wind turbines to come to mind. However, one of the most efficient and reliable renewable energy technologies is right beneath our feet: geothermal energy. With a ground source heat pump (GSHP), you can tap into the Earth’s constant underground temperature to heat, cool and even provide hot water for your home – all while enjoying energy efficiency and environmental benefits.
How ground source heat pumps work
The Earth is an incredible solar collector. Just a few feet below the surface, the ground maintains a steady temperature of around 55 degrees F year-round. GSHPs utilize this constant temperature as a renewable energy source, transferring heat to or from the ground, depending on the season.
This stable temperature is the result of passive solar energy at work. Just as a rock wall outside of a sunlit room can absorb heat during the day and release it after sunset, the Earth absorbs and stores solar energy throughout the year. Unlike active solar systems – such as sunlight shining directly into a room or powering a solar panel – this passive collection process creates a natural and consistent energy reserve beneath your feet. Because the Earth is passively collecting solar energy year-round, it keeps the ground below the surface at a constant temperature.
GSHPs use a series of environmentally friendly fluid-filled underground pipes that absorb the solar energy stored in the Earth and carry it indoors. Using refrigeration principles, GSHPs extract heat from the ground in the winter and bring it into your home. During the summer, the system works in reverse, pulling heat from your home and depositing it back into the Earth to keep your living space cool. The underground pipes and a heat pump power this cycle, ensuring reliable and efficient comfort in any season.
Unlike solar panels, which depend on sunlight in “real-time,” or wind turbines, which need consistent wind speeds, GSHPs provide energy around the clock, 365 days a year. The intermittent nature of solar panels or wind turbines means they only generate energy when the wind blows or the sun shines. Currently, the technology for efficiently and economically storing large amounts of energy from these sources isn’t widely available, making them less reliable during times of high energy demand or unfavorable weather conditions. In contrast, geothermal energy offers consistent, dependable comfort for your home, no matter the time of day or season.
Economic and environmental benefits
While GSHP systems come with a higher upfront cost – ranging from $30,000 to $50,000 – they are an investment in long-term savings and sustainability. Federal incentives and cooperative rebates significantly offset these initial expenses. Currently, a 30% federal tax credit is available through 2032, and Callaway Electric Cooperative offers a rebate of $850 per ton for qualifying systems. The tax credit can even be carried over multiple years, maximizing its financial benefit. Once installed, GSHPs are up to 65% more efficient than traditional HVAC systems. Over their 25-year lifespan (or longer for the underground loops), these systems often pay for themselves within seven years through energy savings. For every $1 spent on electricity to run a GSHP, homeowners typically receive $4 to $5 worth of heating, cooling and hot water. That’s unmatched efficiency and value for year-round comfort. No other renewable resource offers this value or reliability.
Features that enhance efficiency
Another exceptional feature of many GSHP systems is the “de-superheater,” which assists in heating your water year-round. By using excess heat from the cooling process, this feature helps to reduce energy costs while meeting your household’s hot water needs.
GSHPs are also designed for optimal performance at a consistent temperature. Unlike conventional systems that rely on frequent adjustments or “smart” thermostat functions, GSHPs perform best when set to maintain a steady temperature. This design offers unparalleled efficiency for your home.
Installation and considerations
A heat load calculation is essential to ensure that a GSHP system is the right fit for your home. This calculation accounts for your home’s insulation, size and energy needs, helping to determine the optimal system size for maximum efficiency. At Callaway Electric Cooperative, we perform this calculation and also require one from your contractor.
Proper insulation is also critical to getting the most out of a GSHP system. A well-insulated home reduces energy waste and improves system performance, further enhancing the return on your investment. Before pursuing a GSHP system, our team can help you assess if you have enough insulation or if your property would benefit from adding additional insulation.
Ready to take the next step toward geothermal?
Since 1986, Callaway Electric Cooperative has been helping members explore the benefits of GSHP systems and supporting installations with rebates and expert advice.
If you’re considering a new heating and cooling system – or simply want to lower your energy consumption – GSHPs are worth a closer look. With long-term savings, reduced environmental impact and financial incentives, this technology offers an unbeatable combination of comfort, efficiency and sustainability.
To learn more about GSHPs, our rebate program or determine if geothermal energy is the right choice for your home, contact Andy or Clay from our member services team at 573-642-3326 or email CECService@callawayelectric.com.
Thank you for your continued support of Callaway Electric Cooperative.