How the City is working to reduce its own emissions

The City of Montréal’s 2020–2030 Climate Plan has an ambitious target: to bring its greenhouse gas (GHG) emissions down at least 55% by 2030 compared to 1990 levels. To get there, the City is working on five areas, one of which involves decarbonizing building stock. What has been done to achieve that target? And how are Énergir’s decarbonization strategy and grants helping them do it? We’ll tell you about that and more in this article.

Montréal building management and planning (SGPI after its French name) is the department in charge of municipal building decarbonization. And SGPI’s decarbonization strategy is based on three pillars:

Reducing the need for energy through energy efficiency;
Switching to hydroelectricity;
Starting in 2030, possibly purchasing renewable natural gas (RNG) for any residual natural gas needs in certain buildings.

Partial or complete electrification

SGPI’s electrification strategy for is clear—for existing buildings, high-efficiency 100% electrical systems are being studied, while dual-energy using electricity and natural gas will be considered, with a total residual natural gas consumption of no more than 15%. New construction must be 100% electric.

“We have extremely stringent requirements for new buildings,” says Paillé. “That’s not just about the energy source—our envelope and energy efficiency standards exceed those of the National Energy Code, so we know we’re decarbonizing.”

Going further with peak demand management…

SGPI has also been examining new ways to intensify and improve decarbonization of the municipal real estate stock, including demand management and energy efficiency.

“We want to manage our buildings’ power demand better. To stand behind high efficiency electrification and smart decarbonization, we don’t want to overtax our already strained electricity resources,” says Dominic Desjardins. “That would be contrary to the interests of the community.” “By deploying dual-energy in existing buildings where it’s difficult to quickly provide alternatives, we can take the pressure off the grid with natural gas during peak periods even though electricity will be used the overwhelming majority of the time.”

“Still,” he adds, “efficient electrification also has to prioritize technologies like heat pumps and electrical central heating with thermal energy storage. They’re all significantly more energy efficient than resistive equipment [like electric baseboards] so we can decarbonize at lower cost.”

… and energy efficiency

SGPI has sponsored a number of research projects to consider ways of making municipal buildings more energy efficient by validating certain choices, including dual-energy, in collaboration with experts like HEC professors Pierre-Olivier Pineau, an eminent energy management specialist, and Yves-Marie Abraham, an authority on degrowth and sustainable development. Their research has opened up such possibilities as intensified use of buildings, pooling and sharing certain existing spaces (such as gyms) and indoor winter temperature reductions of 1°C and summer temperature increases of 1°C, which is currently the subject of a pilot project involving 30 City buildings.

New ideas to broaden horizons

And SGPI is also investing in innovative new decarbonization projects. “Some of the other things we’re involved in,” says SGPI’s Paillé, “are an urban thermal network, an initiative—truly groundbreaking—to recover energy from the Saint-Michel environmental complex’s leachate and a permanent-column geothermal project in collaboration with Polytechnique Montréal.” “Even if projects aren’t directly related to the City’s housing stock, they open our eyes to new ways of decarbonizing what we do.”

Énergir’s collaboration and support

As can be seen, SGPI’s and Énergir’s decarbonization strategies are well aligned and involve energy efficiency, dual-energy and possible RNG purchases. “At the strategic level, we have the same goal,” says Paillé, “and our working relationship with Énergir is great.” That relationship also translates into financial support: “You can tell that Énergir is really on our side,” says Charles Julien, an SGPI engineer who regularly works with Énergir on grant applications. “They work so hard to get us as much as possible, no matter how complex the project.”

A shared objective

Decarbonizing the building stock of a city like Montréal is undeniably complex—replete with political, economic and operational challenges and constraints. But the efforts of SGPI and the other stakeholders involved in the process have managed to decarbonize part of the City’s building stock and SGPI has many other carbon-reduction projects already in the works. The City of Montréal’s 2020—2030 Climate Plan target seems increasingly within reach, especially with all the partners—including Énergir—on board about the means to get there.

The new Rosemont Aquatic Complex: a great example

Built in 2018 (before SGPI’s decarbonization strategy), the new 5,000 m² aquatic complex includes a semi-Olympic eight-lane and an acclimatization pool. Building heat is provided by a geothermal system and two back-up natural-gas condensation boilers. To reduce overall consumption, various energy efficiency systems were put in, including heat recovery from exhaust air and the dehumidification-system compressors, occupancy sensors in certain areas, high-efficiency LED lighting and a set of variable frequency drives. Energy consumption projections based on simulations show annual savings of over 8,000 GJ, a reduction of about 50% in total consumption. Savings just on natural gas to heat fresh air, building envelope, hot water and pools come to more than 200,000 m³ per year through the many energy-saving measures in place. Through its energy efficiency program, Énergir provided a total of $206,338 in grants² for this project.