Heat pumps are a relatively easy way to shift home heating for single-family homes away from planet-heating fossil fuels. But it's not so straightforward to make the switch for large buildings, particularly residential properties like apartments and condos.
“It's something that requires some thought and a lot of consideration,” said Roberto Pecora, director of building decarbonization at the Zero Emissions Innovation Centre, in a phone interview with Canada’s National Observer.
It takes extensive planning just to figure out when to replace the existing heating system, not to mention having the money to do so. Then, there’s a slew of potential logistical roadblocks, like ensuring there’s enough space to put a heat pump and its water tanks in the mechanical room, when industrial scale pumps can be up to 20 tons and beyond.
A new initiative launched in B.C. aims to create decarbonization plans for 500 large commercial and residential buildings. The decarbonization plan is “meant to highlight some of the potential roadblocks that might be coming up and how to overcome them,” Pecora said.
These plans will identify emissions-reduction and energy-conservation projects that can be integrated into a building owner’s business plan. For example, when a gas-fired boiler is predicted to reach the end of its life, the BC Retrofit Accelerator will provide building owners with options to replace it with climate-friendly options, like heat pumps, Pecora said.
Buildings account for 18 per cent of Canada’s planet-warming greenhouse gas emissions and often comprise more than half the emissions in large cities. In Toronto, buildings make up 58 per cent of the city’s total emissions, mostly from burning fossil fuels for heating, cooling and hot water.
More than 96 per cent of buildings’ emissions come from space- and water heating powered by fossil fuels, so electrifying heating is key, according to the federal government’s green buildings strategy. The Pembina Institute estimates decarbonizing Canada’s buildings sector will require more than $400 billion in capital investment over the next 30 years.
It’s not quite as simple as just hooking up heat pumps to every existing building, though. For starters, not every building has the electrical capacity to add new systems.
“If there's not enough capacity… then you have to start thinking about energy conservation measures,” Pecora said.
“That could be replacing the windows to reduce the heating load. That could be adding insulation to the building, insulation to the roof, making the building more airtight ,so there's less air losses through the building envelope,” he said. “For a domestic hot water system, it could be something as simple as insulating piping inside your building or using highly efficient plumbing fixtures that use less hot water.”
Some climate-friendly upgrades are more straightforward: for example, it is now possible to replace a fossil fuel-powered hot water system with a heat pump.
“Ten years ago, there was no way you could replace that one boiler with one heat pump,” said Pecora, adding that the technology simply wasn’t available in Canada. Now, however, he says there are several options to make this swap.
When it comes to heating systems, it can be a bit more complicated. A lot of buildings use centralized heating, but eventually the heat distribution systems get old and leaky, so it can make sense to instead outfit each apartment unit with a heat pump or mini-split (a ductless heat pump), said Betsy Agar, Pembina Institute’s buildings program director.
Major repairs to heat distribution systems – like air ducts and water pipes, for example – are “hugely disruptive” internal work, while heat pumps can be installed from outside with less fuss, Agar said.
In this hypothetical scenario, the old, centralized system could also continue to provide backup heat during the transition, she noted.
Ultimately, all these factors and more have to be considered simultaneously to find the best solution for a specific building, and these factors vary even more depending on where in the country the building is located.
Switching off fossil fuels is key, but so is energy efficiency. Replacing old drafty windows with higher-quality ones is one of the best-value actions to conserve energy and bring your building to a point where it's easy to decarbonize by switching to heat pumps, Pecora said.
He says replacing or adding insulation is typically more challenging, but there are easier, smaller opportunities to improve a building’s insulation, like putting it around water pipes when it comes time to replace those pipes.
Making Canada’s buildings more energy efficient and switching off fossil fuels is key to achieving climate goals.
Funding is a clear barrier but “we're starting to see some activity in that regard,” said Pecora.
It’s much harder to do large-scale heat pump retrofits for residential buildings compared to commercial buildings like office spaces, said Kit Milnes, vice president of sustainability and resilience at KingSett Capital.
“It's going to cost more than doing business as usual … you really need to figure out how to justify it,” Milnes said.
A lot of it comes down to cost analysis to see if making the switch makes financial sense and what value you can get out of making the switch, Milnes said. This varies by building, but for example, if an apartment building without air conditioning switches to heat pumps that building can now provide tenants with the added value of cooling services since heat pumps can both heat and cool.
Milnes said there’s more action on heat pumps in newly constructed buildings but he thinks retrofitting old residential buildings with heat pumps will pick up steam.
“It's definitely coming,” he said.
— With files from Matin Sarfraz
Natasha Bulowski / Local Journalism Initiative / Canada’s National Observer
Comments
“More than 96 per cent of buildings’ emissions come from space- and water heating powered by fossil fuels, so electrifying heating is key…”
Why no mention of passive solar, either alone or in combination with heat pumps, for heating and how much of the electricity load for heat pumps can be eliminated by its use?
““If there's not enough capacity… then you have to start thinking about energy conservation measures.”
Energy conservation should not be of any lesser importance than energy source conversion. You _start_ your thinking with conservation. If there’s a broken window (analogy for a leaky building envelope) then repair the window either first, or concurrently with, energy source conversion.
““It's going to cost more than doing business as usual … you really need to figure out how to justify it,” Milnes said.”
You justify it by cost. If the cost of status quo isn’t yet high enough to “incentivize” the conversion, it’s obvious the status quo cost must increase until it does.
“Milnes said there’s more action on heat pumps in newly constructed buildings but he thinks retrofitting old residential buildings with heat pumps will pick up steam.”
This is one of the more obtuse and obvious statements.
The entire country has a carbon budget, which ought to be shrinking, year over year, until we reach zero (net, if you must) emissions within a timeframe that’s actually meaningful. Building owners will bother themselves when one of two eventualities occurs:
1. Cost of status quo is on a compelling, urgent, unavoidable, continuing upward trajectory; or
2. Gov’t regulation is put in place to force it.
This article would have done better to concentrate more clearly on the challenges of reducing the combination of emissions and energy consumption across different building types and HVAC systems (e.g. central boilers and pipe network vs baseboard electric).
Also, if ducts and pipes need repair (e.g. due to age or whatever) that situation exists whether or not a central HVAC device is a heat pump or fossil-powered boiler.
And where was mention of district heating?
One last significant thing missing is mention that, first and foremost, we should stop digging. That is, immediately change building codes so that we’re no longer adding to the problem, and creating additional future liability, with every new building constructed.
I think the article is a welcome contribution. It is unreasonable to expect it to be fully technically detailed and to cover all possible considerations. That said, your last item: changing building codes, is really important.