What are some of the Pros and Cons of Geothermal Heating? Geothermal for your home is renewable thermal energy right from your backyard. It’s a great energy alternative if you’re a homeowner looking for a reliable way to heat and cool your home in a greener way, but it’s always good to know the pros and cons before making the switch.
If you’ve already done a bit of research, you’ll see that some resources on geothermal energy mention earthquakes, location-specific demands, and energy fluid as potential cons – rest assured, these concerns are linked to geothermal power plants – and don’t reflect the cons of home geothermal heat pump systems.
We’ve put together a list of the advantages and disadvantages of geothermal energy for homeowners.
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What is geothermal heating for homes?
Geothermal energy is the transfer of heat between below-ground temperatures and your home.
About 5-6ft below the earth’s surface, just below the frost line, the temperature averages 10-15°C all year, even when the weather above-ground is freezing cold or scorching hot. A Ground Source Heat Pump (GSHP) draws from the stable source of heat below-ground.
Connected to sealed pipes called ground loops, the GSHP pulls up the warmth, amplifies it, and then circulates it around the home. During the summer, the earth acts as a heat sink. Heat from the home is transferred back into the earth through the ground loops, keeping the home cool and comfortable.
A geothermal ground loop can deliver all the thermal energy a home needs for heating and cooling throughout the year. This thermal energy is available on-site — right from the backyard — and on-demand.
Interested in learning more about geothermal energy?
See how geothermal heating and cooling works.
Pros of Geothermal Energy
1. Geothermal is a source of clean renewable energy.
Geothermal energy means you no longer need to rely on fossil fuels like oil, propane, or gas to heat your home. These harmful fossil fuels cause environmental damage and contribute to global warming throughout the process of their production, transportation, and combustion.
Switching to geothermal energy drastically reduces your carbon footprint and your home’s greenhouse gas emissions.
The majority of greenhouse gas emissions from buildings are a result of space conditioning (heating and cooling). So, by exchanging your furnace for a geothermal system, you are immediately and substantially decreasing your environmental impact.
A home geothermal system reduces your greenhouse gas emissions equivalent to removing two cars from the road every year the system is running.
The best part is, it’s entirely renewable.
Being a renewable energy source means that geothermal for your home isn’t a resource that will deplete over time. It offers a supply that can reliably sustain its output to meet the energy demand of your home. In fact, geothermal systems operate at 4x the efficiency of traditional heating and cooling — it really does have no problem keeping your home comfortable.
2. It’s an investment in energy independence.
A fossil-fuel reliant home is dependent on expensive resources often transported across provincial, as well as national borders. This also means you’re subject to the politics, price fluctuations, and continual instability of the fuel market.
By collectively reducing our reliance on fossil fuels and switching to renewables, we have a mass impact on easing the strain on resource depletion. As an individual homeowner, heating and cooling your home with geothermal energy protects you from skyrocketing prices as the supply of fossil fuels dwindles and the demand rises.
Geothermal is your own unlimited, highly-efficient, clean energy source sitting beneath the ground of your backyard.
It’s an investment in your independence from volatile markets and pipeline politics. You become your own utility provider for your home’s heating and cooling. As a homeowner, you get to take control of the resources right beneath your feet.
3. Enjoy better air quality and more efficient control.
Geothermal heating and cooling systems are designed to be far more efficient than traditional systems. This has financial and environmental benefits, but a big difference is how much more comfortable your home can feel.
No more fighting over the thermostat! A Ground Source Heat Pump (GSHP) operates efficiently to continuously circulate heated and cooled air on a longer cycle than other systems, providing steady temperature regulation. Continuous, slow heat exchange means that all areas of your home maintain the same comfortable temperature.
Zero-combustion heating and continuous air exchange also mean better air quality in your home. Without a short-cycling furnace intermittently drying out your air, you’ll find your home has more balanced humidity levels through the winter.
The same goes for summer – to cool your home effectively, an Air Conditioning unit needs to remove humidity. It’s very common to see houses with oversized AC units that don’t effectively dehumidify. They meet the temperature set point quickly, meaning they constantly turn off and on. These short cycles allow humidity levels to remain high, making the home feel warmer than it actually is.
Geothermal cooling runs on a long cycle, pulling moisture from the air slowly and consistently for a more stable balance throughout your home.
4. Geothermal energy has a high lifetime value
Geothermal ground loops for your home will last well beyond 50 years with proper installation and correct design, with very little maintenance required for an average system. The heat pump, installed within the house in place of a furnace, has an average lifetime of about 20-25 years.
Even when it does require replacement, the heat pump is a very affordable and easy-to-install component of the system.
Investment that will keep providing a return
Since a geothermal system is non-combustion, it doesn’t go through the same wear and tear as an oil, gas, or propane system. Your cooling is also integrated into the same system, not sitting outside your home as a separate unit, exposed to the elements every season.
Throughout its lifetime, a GSHP and ground loop system can provide you with a monthly return on your investment through energy bill saving
5. Geothermal home systems are low-maintenance.
Once installed, maintenance for a geothermal system couldn’t be easier. The only thing to concern yourself with is checking the air filters every three months and changing them as needed, just like an HVAC system.
An annual inspection to check the performance of the heat pump and the other mechanical components is always a good idea to catch any small issues and perform preventative maintenance.
6. No-combustion heating is low-risk.
A conventional furnace heats your home through combustion. It’s essentially a controlled fire combusting fuel like oil, propane, or gas to generate heat. Products of combustion, like carbon dioxide, nitrous dioxide, or sulfur dioxide can be dangerous if your furnace system isn’t well-maintained.
Geothermal systems rely on a GSHP which does not use combustion to produce heat so there’s no risk of chemical exhaust or carbon monoxide poisoning, unlike a traditional fossil fuel furnace.
Cons of Geothermal Energy
1. Geothermal has a larger upfront cost
The cost of a geothermal system can be intimidating. Depending on the type of ground loop installed, prices generally range upward from $21,000 for a standard-sized home.
There are also additional costs that could apply. For example, ensuring your home is adequately insulated, the ductwork or vent system is set up to evenly distribute air flow, removing an oil tank, or upgrading your electrical panel.
However, there are ways to reduce the upfront cost.
- Opting for horizontal loop installation if you have a larger outdoor space will be less expensive than vertical ground loops.
- Taking advantage of renewable energy incentives like the Greener Homes Program which is offering homeowners up to $5,000 in grant money for energy efficiency retrofits.
- Retrofitting your home with upgraded insulation, new windows or doors, or anything that will increase the household’s heating/cooling efficiency can reduce the energy demand of your home. A lower energy demand means you can opt for a smaller, therefore less expensive, system.
The Greener Homes grant money could be used to cover the cost of a Ground Source Heat Pump (GSHP) as well as some retrofits that reduce your home’s energy draw.
Also consider the rising cost of oil, propane, and gas – which are only set to increase as we deplete the supply of these non-renewable resources. A few years from now, you could be facing the rising cost of fuels and increasing carbon pricing for simply heating your home.
Ultimately, geothermal is a long-term investment in your home’s carbon footprint, comfort, and value.
2. Ground loop installation can disrupt the appearance of your yard.
Horizontal ground loops are installed 6ft below-ground, parallel to the surface in trenches 300ft long x 6ft wide x 6ft deep. Vertical ground loops are placed perpendicular to the surface and require boreholes of 3.5-5inches in diameter down to a maximum depth of 500ft.
Both options do require large excavation equipment to be moving around your backyard – for 1-2 days on average — so the process could disrupt grass growth or landscaping. In the case of horizontal loops, the surface will be put back to a rough grade.
With grass growth and time, you shouldn’t be able to notice it. During excavation, contractors reserve topsoil to fill in the trenches or boreholes and level the mound as much as possible to reduce its appearance in the meantime.
The scale of horizontal loops makes them only suitable for homes with larger properties, however, if you’re concerned about modifying your backyard you can always opt for vertical loops which take up a significantly smaller surface area.
Remember that the cosmetic impact is only temporary and really it should be a sign of achievement for decarbonizing your home – and increasing its value.
3. GSHPs require electricity to run.
The Ground Source Heat Pump (GSHP) connects the ground loops to your home’s ductwork or radiator system, transferring the heat from the earth into your home.
While the mechanical components of the system are extremely efficient, they do require electricity to run. Switching to geothermal means that your fuel bills will disappear, but you still have to pay for the electricity to power the heat pump.
The heat pump extracts energy at 4x the efficiency of traditional heating systems. To provide a simple example we’ll use dollars and cents to illustrate:
For every $1 you spend on powering the GSHP it outputs $4 worth of thermal energy into the home.
The closest comparison with a fossil fuel system is a high efficiency natural gas furnace burns $1 worth of gas to provide $0.98 worth of heat into the home. Burning a fossil fuel can never be 100% efficient, as there are losses in the combustion process.
So essentially, the GSHP only requires electricity to move heat between the ground loop and your home. The thermal energy is free, you just pay to move it.
You become your own heating and cooling utility provider, independent from the high costs of oil, gas or propane.
With carbon pricing gaining momentum, rising fuel costs, and the current availability to renewable energy incentives for homeowners, there’s never been a better time to take the plunge on geothermal.
Thinking of investing in renewable energy for your home?
If you’re looking to make the switch to geothermal, check out the Greener Homes Program to see how you could use $5,000 to prepare your home for the transition.