What You Should Know About Geothermal Heating for Your Home
If you have been paying attention to alternative energy news lately, you may already know that geothermal energy is an important conversation topic. But what is geothermal heating, and is it a viable option for Canadian homeowners? Here's what you need to know.
How Geothermal Heating Works
During a typical Canadian winter, it's hard to imagine that any part of the earth is warm. However, if you go far enough below the earth's surface, you'll encounter a relatively warm, consistent temperature.
That temperature consistency is the key to the success of geothermal heating. Picture a series of underground pipes (closed loops) installed either vertically or horizontally below ground. A geothermal system pulls below-ground heat up through these loops. That heated air travels through your ducts the same way it does in a conventional HVAC system.
Geothermal energy, however, has greater long-term potential as a sustainable resource: it has almost 300% efficiency compared to the 90-95% efficiency of a high-efficiency furnace.
Expectations and Implications
We hear almost every day about climate change. Alternative energy is a big political topic.
But politics aside, geothermal heating offers great promise to homeowners and businesses who are concerned about their carbon footprint. For example, geothermal systems only use one electrical unit to drive nearly five heating (or cooling) units in a building. That's not a bad energy ratio.
Geothermal heating is not without controversy; however, some arguments against it are based on simple untruths or misunderstandings. Writer Jay Egg debunks a few myths about geothermal heating in a 2013 National Geographic article. For instance, a big concern for homeowners is the cost. While this concern is valid (it costs more to dig underground), remember that provincial grants can greatly cut the costs of a geothermal retrofit on your home energy system.
Here are a few other things to expect from a geothermal system:
- Geothermal systems cool the air in the summer and warm it in the winter for year-round efficiency.
- Geothermal heat can also heat the water in your water heater tank.
- A geothermal system operates quietly and safely. You won't miss the old, noisy fan unit on the patio.
- Geothermal systems last a great deal longer than conventional heating systems. Earth loops alone may be warrantied for up to 50 years.
- Geothermal systems take longer to install than traditional systems.
- Horizontal loops (in larger yards) may have half the installation cost of a vertically-installed earth loop.
- Geothermal systems don't fully eliminate electrical consumption. Expect your geothermal heat pump to operate somewhere between 100 and 200% efficiency, depending on whether your electricity source is coal or gas powered.
- Geothermal heat will be a sustainable resource in the future.
How the Installation Process Works
If you're considering a geothermal retrofit, you may have concerns beyond cost. It is true that geothermal systems do take more time to install, but if you communicate with your installer you won't be overly inconvenienced.
Here's a basic outline of installation steps:
- Your HVAC specialist will inspect your current system, ductwork, and yard space.
- After the installers determine your limits, you'll decide on a horizontal or vertical earth loop installation.
- Installers can usually finish horizontal systems in a couple of days. They will lay pipes in trenches.
- Vertical system installations can vary depending on earth and bedrock conditions (or underground aquifers). Expect at least 2 days - possibly more. Vertical systems usually require less pipe than horizontal systems.
- Your installer may provide a heating/cooling calculation to ensure that the seasonal temperature fluctuations don't overload the system.
- Once the earth loop is completed, your installer will connect it to the new geothermal unit (which is generally about the same size as your old, conventional furnace).
How to Know if Geothermal Is For You
To understand if geothermal heating is the right choice for your home, talk to others who have geothermal systems. Your HVAC specialist should be able to provide names of customers you can contact.
It's also a good idea to read a few online forums. Keep in mind, though, that negative commentary may only be reflective of a few customers' experiences, rather than the norm. For this reason, it's important to hire a trustworthy HVAC company so you feel confident that your installation will be done properly.
When you talk with area residents whose homes use geothermal energy, ask about their monthly energy bills. Pay special attention to the source of the electricity component. Coal-powered electricity costs the most, while gas-powered electricity is lower. Solar and wind-powered electricity is the best option of all, if it's offered in your area.
In the end, even if you decide that geothermal heating systems are not possible for you right now, you'll come away better informed when you make the change in the future. As always, your friendly HVAC technicians at East Side Ventilation can tell you more.