Everyone is looking for HVAC solutions that are good to the earth without breaking the bank. Leading the industry in sustainable HVAC solutions are geothermal heat pumps. One of the most common reasons to invest in geothermal systems–besides reducing emissions and increasing property value–is the guaranteed improvement to air quality. Read below for an introduction to how geothermal heat pumps work, their benefits, and whether you should consider installing them in your space.
An Introduction to Geothermal Heat Pumps
What Are Geothermal Heat Pumps?
Geothermal heat pumps are a clean, efficient, and cost-effective heating and cooling system that uses the earth’s constant underground temperatures to heat, cool, and supply hot water. Like the name suggests, they are literally a pump that transfers heat from the ground, taking advantage of earth’s temperature throughout the seasons. More specifically, about 30 feet below the ground, there is a constant temperature between 50 and 59 degrees Fahrenheit year-round. Thus, in the United States at least, underground soil is typically colder than the air in the summer, and warmer than the air in the winter. This is why geothermal heat pumps can take advantage of the constant temperature for proper heating and cooling. 
How Do They Work?
There are three parts to a geothermal heating system: the underground heat collector, the actual pump, and the heat distribution system. Here’s how they work:
- Underground heat collector: In order to use the earth’s thermal storage, a series of connected pipes are installed (vertically or horizontally) underground beneath the building it’s servicing. This pipe loop circulates a fluid that either absorbs or deposits heat to the surrounding soil, depending on whether or not you’re heating your space or cooling it.
- Heat pump: When ambient temperatures are colder than the ground (winter), the heat pump removes heat from the heat collector’s fluid, concentrates it, and uses it to heat the building. When the ambient temperatures are warmer than the ground (summer), the heat pump removes the heat from the building and deposits it underground to cool the building.
- Heat distribution system: In order to distribute the hot or cold air, conventional ductwork is typically used.
Benefits of Geothermal Heat Pumps
Energy Efficiency & Environmental Impact
In terms of sustainability, there are three benefits to using a geothermal heating system as opposed to oil or gas-based systems:
- Geothermal energy is virtually emission-free
- Geothermal energy doesn’t require combustion like gas or oil systems
- Geothermal systems last longer, requiring less resources to constantly replace and throw away parts
Cost Savings & Reliability
In terms of reliability and affordability, there are three benefits to using geothermal energy as well:
- They’re quieter than other systems because they don’t require noisy outdoor condensing units like traditional AC
- They help improve indoor air quality
- There are financial incentives to using them besides simply being a more affordable option: some state governments and utility companies offer tax incentives or cash rebates for installation
Maintenance & Potential Limitations
Geothermal Heat Pump Maintenance
Luckily, geothermal heat pumps are fairly low maintenance and known for lasting upwards of 15 years. But like anything else, frequent maintenance will keep them running longer. That being said, geothermal heat pump maintenance is fairly simple. Here are some things to look out for:
- Checking and adjusting coolant levels for proper heat transfer
- Ground loop inspection for leaks, soil erosion, or other damage
- Cleaning and replacing air filters
- Inspecting and cleaning air ducts
- Checking and tightening electrical connections
- Inspecting and lubricating motors, fans, and bearings
- Testing thermostat calibration
- Verifying the proper functioning of safety switches and controls
- Inspecting piping for leaks, corrosion, or insulation damage
- Checking for proper water pressure and flow in the hydronic systems
Potential Limitations
The power of geothermal energy is an incredible technological advancement; but there are some places in which it can’t be used, geologically speaking. The heat flow from the center of the earth is constant, which makes it possible for almost any place on earth to access that heat. Essentially, the amount of heat available depends on the location. To replace conventional power plants with geothermal electricity, you need a temperature of at least 230 degrees Fahrenheit, which isn’t available in all places–though it is available in most. It’s also important to consider the installation; it is difficult to install geothermal heat pumps in urban areas because you need to dig into the ground to get there. The installation not only requires lots of space (especially if you’re installing the pipes horizontally) but it’s also easier if you’re not drilling through concrete.
Conclusion
Geothermal heat pumps are a sustainable HVAC solution for almost anyone. They’re cost-effective, emission-free, and incredibly reliable. Many commercial and residential locations are making the switch to geothermal heat pumps because of the nearly endless list of benefits it provides. Talk to a professional today to learn more about how you can save the earth (and some money) in your own backyard.