"Don't buy geothermal," it said. A tiny voice in the Facebook wilderness, it described a poorly performing, six-year-old unit and painted a picture of winter nights "huddled around a fireplace." It concluded: "geothermal simply doesn't work in Canada."
However, Shannon Kyles's voice – indeed her whole personality – is anything but tiny. At 62, the recently retired Mohawk College architecture instructor is outspoken, funny, articulate, passionate and … peeved. In 2011, she moved an 1830s Regency cottage from Ancaster, Ont., to Prince Edward County. And because much of it had to be reimagined, she had it built with insulated concrete forms for walls, a radiant-heated floor in the basement and a roof rated at R40. The cottage, which she calls "The Gryphon," also has a geothermal unit (also known as "geoexchange") for its heating and cooling needs; in this case, a horizontal bed of closed-loop pipes buried six feet below ground that spread over about an acre of her property.
And that geothermal system is what has Ms. Kyles shouting her tale of woe to anyone who'll listen. "They told me it was a very large system and I thought, 'Great, I want it to work so if it's a little larger I'm happy to spend a little bit more money up front because I know there's going to be cost-savings in the end.'" So, after spending $50,000, it was a surprise when she "turned it on and it wouldn't work."
In principle, a geothermal system is easy to understand: Refrigerant in the buried pipes (a.k.a. coils) exchange heat or cold from the home's interior (depending on the season) using an electric heat pump, since, outside, below-ground temperatures remain at a constant 8 C to 10 C. The newly cooled or heated air is then circulated via ducts or radiant floors. It's an elegant system that doesn't require the burning of fuel.
A typical residential geothermal system.
Deborah Baic/The Globe and Mail
In practice, however, the complex network of sensors, manifolds and moving parts means many things can – and do – go wrong. After blaming her "overly dusty" home and spending a day cleaning a main sensor, Ms. Kyles' installer (no longer in business) voided her warranty. When that cleaning didn't work, the installer called the manufacturer, NextEnergy, who determined the problem was electrical.
That was 2012. By summer, when her air conditioning didn't work either, Ms. Kyles began to wonder if she'd purchased a lemon, or if geothermal just wasn't up to Canadian temperature extremes. In 2013, more visits, more repairs and the realization that her home would never reach more than 20 C in winter. Each year since, she's had something tweaked or repaired. And she still hasn't seen any savings: For instance, her electricity bill for January, 2018 was $800, and she routinely pays more than $4,000 a year. When Hydro One notices stating she was paying a great deal more than her neighbours started arriving in the mail, she started to ask around and that's when she learned that many folks with geothermal pay through the nose.
So why, she wonders, does the government offer grants and promise savings? "Is Green Ontario really promoting geothermal to people on the basis of [biased] sales information?" The last straw was when a former installer told her: "'If you put in geothermal, you have to have a second furnace.' Nobody told me that I need two furnaces!"
A geothermal grid was buried at the rear of Jason Alleyne’s property.
quantum geothermal
Conversely, when building a new, sustainable home complete with radiant floors on three levels, walls of insulated concrete forms and solar panels, Jason Alleyne knew, going in, that he'd need a backup gas furnace to compliment his geothermal system.
"The geothermal isn't strong enough to winter on its own, so the [traditional] furnace is hooked up to the tank that feeds the floors … so they carry the load jointly in wintertime, and in summer, that tank feeds the air handler at the top of the house."
Originally from Trinidad, the 46-year-old actuary and his architect, Paul Dowsett of Sustainable.TO, crunched many numbers back in 2010 since "the mechanical engineers and the people who are going to provide that service, of course they want to [install] the biggest unit … so you have to actually look at what you need in terms of energy," he explains.
The interior hookups of the geothermal heating system in Mr. Alleyne’s home.
Quantum Geothermal
The best way to do that, he continues, is to "pick either the summer period or the winter period as your major energy need, and for us, it was more the summer." Build the same house in drier Germany rather than humid North York and one would likely choose winter, he explains. Then, Mr. Dowsett adds, one must spend a great deal of money on insulation, since geothermal "works very well with an air-tight, well-insulated building" that acts in much the same way as a "Thermos bottle."
Completed in 2012, Mr. Alleyne's home consumes about $200 of electricity per month and requires extra help (and fuel) only in January and February (because his lot enjoys great southwest exposure, passive solar heat warms his floors during the shoulder months). In summer, it stays cool and dry with zero mechanical back up, unless one counts his ceiling fans. The vertical system (the coils go down 600 feet) cost about $25,000 rather than the $75,000 he might have paid had he focused his numbers on winter optimization.
The key to this success might be research: In addition to working closely with Mr. Dowsett, Mr. Alleyne talked to dozens of geothermal owners in Canada and elsewhere since, with any new technology, there are "not yet enough data-points to get scientifically accurate" data.
And while one doesn't have to be an actuary or math nut to consider geothermal, Mr. Alleyne cautions that there is a certain amount of monitoring and thermostat tweaking required to get the balance right since "there is no one system that can do it all.
"If you're thinking that you just want to go on auto-pilot, maybe think again."