If you’re looking for the ultimate in efficient heating and cooling for your home, geothermal HVAC should be on your radar. It’s hands-down the most efficient method of keeping your residence comfortable. It also comes with some significant advantages over other types of HVAC systems. Here’s an overview of geothermal HVAC, including how it works and its advantages and disadvantages.
What Is Geothermal HVAC?
Geothermal HVAC systems are heating and cooling systems that use heat pump technology to function. However, they don’t work the same way as the heat pumps you often see advertised by HVAC companies. Those use the outdoor air as a heat sink in cooling mode to expel heat from your home. They use the outdoor air as a heat source to capture heat energy to warm your home in heating mode. Geothermal systems, by contrast, have a buried ground loop to use the earth for the same purposes.
How Does Geothermal HVAC Work?
The key to understanding geothermal HVAC systems lies in understanding their two principal components. The first is a heat pump unit, which resides inside your home. Heat pumps use the refrigeration cycle to move heat from place to place. They employ a refrigerant as a heat transport and transfer medium. It’s the same way an air conditioner works. The big difference is that heat pumps can work in either direction by engaging a reversing valve. That changes the direction in which refrigerant flows through the system and, hence, the direction in which it moves heat.
The second component is a buried ground loop. It’s precisely what it sounds like, a long line of heat-conductive pipe in horizontal loops buried a few feet below ground. Alternatively, geothermal HVAC systems can use vertically installed pipes in deep wells. This is the preferred solution for homes that don’t have enough room for horizontal loops. The ground loop circulates a fluid — typically a mix of antifreeze, water, and refrigerant — by using a small pump.
Geothermal HVAC systems bring the circulating ground loop fluid and the refrigerant together by passing them through a heat exchanger. In cooling mode, the heat pump absorbs heat from your home’s air using its refrigerant. Then, it transfers that heat into the loop fluid, which deposits it into the ground surrounding the loop. In heating mode, the process reverses. Instead, the heat pump extracts heat from the loop fluid by means of the refrigerant. It then uses that heat to warm your home.
The secret to the efficiency of a geothermal system is the stability of the ground temperature. Just a few feet below ground, you’ll find stable temperatures around 55 degrees Fahrenheit year-round. Because the sun’s radiation doesn’t penetrate that deep, those temperatures don’t rise in the summer. Nor do they drop in the winter, since earth is an excellent insulator against cold air. As a result, a geothermal system isn’t affected by the outside temperature in the way air-source heat pumps are. It always has a place to efficiently deposit or collect heat as needed.
Geothermal HVAC Advantages
As previously mentioned, geothermal HVAC systems are the most efficient heating and cooling solution available. According to the Department of Energy, they operate at between 300% and 600% efficiency. For comparison, most central ACs hover between 200% and 400% efficiency, depending on the outdoor temperature. Gas furnaces fare much worse, with the average model being 81% efficient. Even the most efficient gas furnace is only 98.7% efficient.
Another advantage of geothermal HVAC systems is their fantastic longevity. A geothermal system’s indoor components may last as long as 25 years. A geothermal system’s ground loops may last up to 50 years. As a result, when your first geothermal heat pump wears out, you can replace it and reuse the ground loops. That means geothermal HVAC systems have very low lifetime ownership costs relative to other systems.
Geothermal HVAC systems can also help lower your home’s water heating costs. You can add a desuperheater component that augments your home’s water heater. Essentially, it uses waste heat from the HVAC components to heat water. That lowers the volume of water your existing water heater must heat instead. When your geothermal system is in cooling mode, you get to use heat collected inside your home for water heating. Many homes can eliminate water heating costs for at least half the year that way. And even when your geothermal system switches to heating mode, it will still augment hot water production.
Geothermal HVAC Disadvantages
The most notable disadvantage of a geothermal HVAC system is its up-front cost. A new system can cost between $10,000 and $30,000. Most of that expense goes toward the installation of the ground loops. If you have plenty of space, digging trenches for horizontal loops can help contain costs. However, you can expect higher installation prices if you need vertical wells drilled instead.
The other drawback to geothermal systems is that their ground loops are vulnerable to tree roots and earthquakes. While the latter don’t occur frequently in our area, the former pose a threat on most properties. Damaged ground loops are challenging and costly to repair.
Is Geothermal HVAC a Smart Investment?
Since geothermal HVAC systems are so costly, it’s natural to wonder if they’re a wise investment. The answer is an unequivocal yes unless you plan to sell your home soon. In that case, it would be unlikely you’d recoup your investment. Otherwise, you can expect your energy savings alone to pay for your geothermal system in five to 10 years. Plus, the energy savings from a geothermal system should only increase as our summers grow warmer. Air-source heat pumps and ACs decline in efficiency in extremely hot weather. Geothermal HVAC systems don’t have that problem.
Also, there may never be a better time to have a geothermal HVAC installed. Right now, you can claim a tax credit worth up to 30% of your geothermal system’s total cost. Best of all, there’s no maximum dollar value, and the credit, though non-refundable, is eligible to carry forward. That means you can use part of the credit annually to eliminate your tax liabilities until it runs out. This guarantees you the maximum benefit of the credit. However, that credit will shrink after 2030, so you only have five years to take advantage of the full amount.
Ronkonkoma’s Geothermal HVAC Experts
To get the maximum benefit from a geothermal HVAC, you need an expert to design and install it. Cool Power LLC is the local geothermal HVAC system design and installation leader. We have served locals here since 1975, and we possess deep expertise in the HVAC field. We’re members of the Air Conditioning Contractors of America, so we adhere to the highest professional standards. We’re also a PSEG Cool Homes Partner specializing in efficient comfort systems. For installations, we even offer financing options on approved credit, which can be extremely useful in covering a geothermal system’s cost.
If you’re considering a geothermal HVAC for your home in or near Ronkonkoma, NY, contact us at Cool Power LLC today!
