After years of inaction on climate change, the decade ahead has become the bracket in which humanity gets one last opportunity to at least contain the warming crisis. While mitigation efforts targeting transportation, industry and the energy sector remain mired in conflict, the world of buildings – responsible for about 40% of all carbon – offers vast and relatively uncontroversial opportunities to reduce emissions, create new jobs and produce more livable built environments. Here are five solutions that should be on every policy-maker’s radar.
1. Chop down embedded carbon in new builds
The latest generation of energy-efficiency regulations laid out in provincial building codes is aimed at decarbonizing the long-term operations of a building – heating systems, insulation and other measures to cut energy consumption. But given the critical importance of stabilizing global temperatures by 2030, Drew Adams, an associate at LGA Architectural Partners, says developers and regulators need to refocus their efforts on reducing the carbon embedded in building materials. Concrete, steel and plastic foam insulation together can account for 50 to 75% of a building’s total emissions in its first decade.
To get there, provincial building codes and municipal planning departments should require developers to produce life-cycle analyses as part of the permitting process, with the goal of using regulations and incentives to promote the use of low-carbon concrete, mass timber or mineral-based insulation, like stone wool. California and Washington State are both experimenting with “buy clean” laws that require construction firms building public projects to use carbon-reduced construction materials.
While energy-efficiency measures such as solar panels and triple pane windows can be added to existing buildings to reduce emissions, a structure made out of concrete and steel will never reverse recoup the carbon used to make those materials. As Adams points out, it’s better to embed less carbon at the front end.
2. Get creative about retrofits
With ambitious new building codes in jurisdictions like British Columbia, the City of Vancouver and the City of Toronto, most new buildings will soon achieve or approach net-zero emissions. And climate-oriented reforms to the national building code, including new resilience standards to protect buildings from flooding, for example, are now in development.
The more intractable problem, says Scott Kennedy, a partner at Cornerstone Architecture in Vancouver, involves unlocking the financial incentive for homeowners and landlords to invest in energy retrofits.
The next generation of incentive programs, he says, should always begin with straightforward “building envelope” improvements: triple-pane windows, insulation, ventilation. But to go deeper, we’ll need to find ways to encourage Canadians to invest in more cutting-edge technologies. For example, to get homeowners to reduce natural gas consumption, there are now relatively affordable electric heat pumps, including one from a firm called Sanden. With a highly efficient compressor, it concentrates external ground heat and uses a carbon-dioxide-based refrigerant to rapidly transfer that energy to a hot water tank. “These are important products coming into the market place,” says Kennedy.
He also points to emerging approaches to commercial efficiency retrofits, such as “portfolio energy optimization.” The idea is to develop a business model around energy retrofits by aggregating savings across a larger portfolio of commercial buildings. Landlords get better-performing buildings, while the aggregator pockets energy savings created by the improved systems.
3. More modular or prefab construction
While buildings shoot up in high-growth cities like Toronto, the construction industry still uses many traditional approaches, some of which contribute to unnecessarily high emissions caused by leaks or insulation gaps. Some green-building advocates want developers to rely more on prefabricated components, such as wall or window panels that are preassembled in a factory with better quality controls that ensure any gains from higher-performing materials aren’t squandered due to hasty installation.
A recent market study by Frost & Sullivan projected 6.3% annual growth in the global modular construction sector, with that expansion driven by reduced costs as well as an increased emphasis on sustainable building techniques. As the report noted, “Prefabricated buildings are increasingly being perceived as sustainable solutions for construction projects due to a growing usage of materials, such as timber and aluminum composites, that are more energy efficient than concrete.”
4. Give mass timber a boost
According to architect Richard Witt, a principal at Quadrangle and designer of one of Toronto’s first tall-timber projects, the city has more such projects in the approvals pipeline than any other place in North America. The problem, however, is material supply, which is more than a little ironic in a country with as much wood as Canada. There are only a few manufacturing facilities for tall-timber components –cross-laminated beams, for example – and they can’t produce nearly enough supply to sate all that demand. “There’s a lot of chatter” about investment in large-scale engineered-wood plants, he says, but so far nothing more.
Witt argues that Ottawa and the provinces should create economic development incentives for investors to build such facilities. The government, he notes, invests in other industries (automobiles, fossil fuels), so why not tall timber? To contain the risk to investors, the federal government could kick in R&D grants, while municipalities could tweak building-permit fees and development charges to favour projects that use engineered wood components. Municipal planners could also fast-track tall-timber building projects, which can be constructed more rapidly than conventional structures, as a means of priming the pump.
5. Look for renewable energy in unexpected places
Environmentally conscious architects and renovators now install heat-recovery devices that can capture and recycle energy lost when hot water goes down the drain. But a Toronto start-up, Noventa Energy Partners, is looking to double down on this idea by using the temperature of sanitary sewer water to help heat and cool larger buildings. Noventa holds the North American licences for a technology developed and commercialized in Germany about 15 years ago and marketed by Huber Technology.
According to 2017 UN statistics, 300 billion litres of waste water are dumped into sewers in Europe and North America each day. Based on average waste-water temperatures of 20 degrees Celsius, that’s the equivalent of 150 billion kWh of energy – almost twice the annual daily demand in the U.S.
The fact that waste water is approximately room temperature makes it an attractive source of heating and cooling. Huber’s technology extracts the thermal energy from the waste water and uses it to replace natural-gas-fired industrial chillers, for air conditioning. “There are a lot of buildings that become attractive for heat recovery,” Fotinos says, citing hospitals and hotels.
Noventa is working on a handful of pilot projects in Toronto approved last summer. Using Huber’s business model, the company supplies and maintains the equipment, pays a portion of the energy savings to the building owner and the city, and keeps the balance to finance capital and generate a return for its investors.
What’s clear is that cleantech, green building technology and the right combination of incentives can cut the carbon in our built form without significant economic or industrial upheaval. It behooves policy-makers to rapidly find ways to spur all the pent-up innovation and investment in this space.