It’s a stereotype, but it’s true — Canada’s winters are cold. And many of us stay toasty by burning fossil fuels such as natural gas in our furnaces or the boilers that feed our radiators.
In an effort to cut down on greenhouse gas emissions and meet targets to reduce global warming, the U.K. has proposed banning fossil fuel-based heating in new homes by 2025. Cities in the states of California, Washington and Massachusetts are also trying to phase out natural gas.
If your home is hooked up to a district heating system, where a utility supplies heat directly, you may be able to tap into a variety of greener energy sources.
But if your home relies on its own individual heating system, as most do, what are the alternatives to fossil fuels and will they work in the colder parts of this country?
Here’s a closer look.
How much does heating buildings contribute to CO2 emissions?
About 45 per cent of Canada’s emissions come from burning fossil fuels to make energy, including heat and electricity — quite a bit more than transportation (28 per cent), the Prairie Climate Centre reports. Of that, about half is from houses, shops, schools and other private and public buildings. The other half is from industry.
Nearly 70 per cent of the energy used in the residential sector comes from fossil fuels, a 2014 study estimated. Forced air furnaces and hot water or steam boilers with radiators, which most often burn fossil fuels such as natural gas, make up a majority of the primary heating systems in Canada, Statistics Canada reports.
How important is it to decarbonize heating?
“Very important,” said Fin MacDonald, program manager of the Zero Carbon Building program at the Canada Green Building Council, a non-profit that advocates for and certifies green buildings. In provinces such as B.C., Ontario and Quebec whose power grids don’t produce a lot of emissions, fossil fuel combustion from buildings represents the biggest source of carbon dioxide, he said.
That’s certainly the case in Vancouver, where more than half the greenhouse gas emissions come from buildings, said Brady Faught, green buildings engineer with the city.
While people may be concerned about a car idling for 10 minutes, Faught says “your house is basically idling all day.”
And it’s not just the gas it’s burning that’s the problem. Natural gas or methane — a greenhouse gas that traps heat far more effectively than carbon dioxide, causing much more global warming per molecule — also leaks from the entire distribution system used to deliver gas to people’s homes and furnaces, Faught said.
How can emissions from home heating be reduced or eliminated?
Buildings heated with fossil fuels can cut some of their emissions by reducing the need for heating through things like better insulation and reusing “waste” heat.
But in order to make a big difference, the green building industry is looking to electrify heating.
“The only fuel that we can truly make 100 per cent carbon neutral is electricity,” MacDonald said.
That’s why the City of Vancouver is trying to come up with regulations and incentives for homeowners to electrify their home heating.
“The ultimate goal is zero emissions,” said Faught, whose job is to develop policies to encourage green retrofits for single-family homes in Vancouver.
In provinces with an electrical grid based mostly on hydro, nuclear or other non-fossil fuel energy sources, such as Ontario, Quebec and B.C., replacing a gas-burning furnace with an electrical heating system can nearly eliminate a home’s emissions.
In some provinces, such as Alberta and Saskatchewan, power is largely generated by burning fossil fuels. For now, homeowners who want to cut heating emissions need to go beyond electrification and also install green power generation, such as solar panels.
What are some of the options for heating your home electrically?
- Baseboard heaters are the most common option in use across Canada. They’re powered by electrical resistance heating, just like your toaster and oven. Electric forced air furnaces, electric convection heaters and electric radiant floors also use electrical resistance heating.
- Heat pumps are far more efficient, because they simply move heat into your home, rather than generating heat. There are two kinds:
- Air source heat pumps, which draw heat from the air. (Yes, it can work even when it is very cold outside, just as your freezer can use its heat pump to cool itself to -18 C in a 20 C kitchen.)
- Ground source heat pumps, which draw heat from the ground and are sometimes referred to as geoexchange or geothermal heat pumps. However, MacDonald says the industry is trying to move away from calling it geothermal, as it gets confused with geothermal power generation.
What about solar?
Solar power is useful for generating green energy to run devices like heat pumps in provinces with a fossil fuel-based electricity grid.
However, there’s also solar thermal energy, where heat is collected directly rather than by generating electricity.
MacDonald said that tends to be more expensive than other options and requires lots of space for the solar panels. Because most of the heat is collected in summer, it also needs to be stored somewhere.
“If you have a pool, perfect,” he said. If you have a ground source heat pump, in theory you can also store the heat in its underground heat exchange loop.
Turnbull and Faught both think solar technology is not quite ready for heating individual homes in Canada (although solar thermal heating with storage has been successfully tested for district heating in Okotoks, Alta.).
What are governments doing about this?
In Canada, the federal government is holding public consultations on proposed changes to the National Building Code and its National Energy Code for Buildings. Some jurisdictions such as Vancouver are also coming up with their own regulations and incentives to encourage electrification, especially in new homes.
The city’s climate emergency response report proposes that by 2025, all new and replacement heating and hot water systems should be zero emissions.