At Ottawa’s 100 Murray St., the push for a ‘zero carbon’ building

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To cut energy costs and promote a sustainability agenda, Sun Life Financial Inc. and its real estate subsidiary, Bentall Kennedy, launched an experiment with a commercial building in Ottawa’s ByWard Market.

Aiming to reduce the six-storey building’s “carbon footprint” to as close to zero as feasible, the companies approved a two-pronged strategy: Make aggressive energy-reducing changes to the building’s hardware and energy management, and purchase enough renewable energy from Toronto-based Bullfrog Power to offset greenhouse gas emissions from the energy still required used to run the building.

As a result, 100 Murray St. is the first commercial building in Canada to be certified as “zero carbon performance.”

The Class A commercial building was already energy efficient when Sun Life purchased it in 2011, garnering top ratings under the federal government’s Energy Star program.

The “zero carbon" designation comes from the Green Building Council, which handles certification for Leadership in Energy and Environmental Design (LEED) standards in this country.

While the certification yields some green marketing appeal, company officials say the effort was driven by hard-core business values such as driving down costs and attracting tenants.

“Our foremost responsibility is creating sound and long-term value for our clients and their beneficiaries,” said Anna Murray, vice-president for sustainability for Bentall Kennedy. The company manages buildings on behalf of institutional clients in Canada, in addition to operating as Sun Life’s real estate arm across North America.

“Our strategies have been shown to enhance tenant loyalty, health and satisfaction, as well as being able to increase net operating income and reduce tenant obsolescence,” Ms. Murray said.

For Sun Life, the effort at 100 Murray St. is both a worthy investment and something of a demonstration project as the company looks to cut costs and lower its greenhouse gas emissions throughout its real estate holdings, company vice-president Alanna Boyd said.

Like insurance companies around the world, Sun Life is keenly aware of the risks climate change poses to its long-term financial health. The company set a target to reduce greenhouse gas emissions in its real estate holdings by 20 per cent before 2014 levels by 2020, and by 30 per cent by 2030. It’s now on track to exceed the 2020 goal, Ms. Murray said.

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At 100 Murray St., Bentall Kennedy started with a highly efficient structure equipped with triple-pane windows and airy design that maximizes natural light and passive solar warming in winter, and upgraded it with LED lighting, motion-detection sensors in light switches and high-end heating, ventilation and air conditioning (HVAC) controls.

“The key element is the control system,” said Brandon Malleck, the Bentall Kennedy engineer who ran the project. “We’re controlling the building based on the number of people in the space. ... We track the amount of CO2 in the space and we bring in the appropriate amount of fresh air, so we’re not bringing in lots and lots of air when it’s -30 outside and then you have to heat the air to it to 22 degrees Celsius.”

Conditions are continuously monitored and HVAC control can be adjusted at 15-minute intervals to ensure maximum efficiency.

The landlord also works with the tenants in the building to manage energy consumption, as well as waste and water use. Workers are encouraged to turn off lights and televisions, and shut down their computers rather than leave them in sleep mode.

While Bentall Kennedy and Sun Life focused on energy consumption, there was no effort to generate power within the building itself.

Solar panels can provide a significant proportion of the electricity needed for a single-storey family home, or a low-rise commercial or institutional building that has a large roof. But they’re not practical on a multistorey office tower that has a small rooftop, partially shaded by neighbouring high-rises, said Mark Hutchinson, vice-president of the Canada Green Building Council, which worked with Bentall Kennedy on the project and will soon relocate to 100 Murray St.

While investments in efficiency pay off through lower energy bills, purchasing renewable power to offset on-site energy use is more difficult to justify in accounting terms. Bentall Kennedy’s Ms. Murray insisted, however, that the “zero carbon” certification helps the company attract and retain tenants.

The company won’t say how much renewable power it purchased. But it was enough to account for emissions associated with electricity pulled from Ontario’s grid, as well as the gas burned for heat in the building. (In the first six months of 2018, natural gas-fired power accounted for 5.3 per cent of the grid’s electricity supply, according to the Independent Electricity System Operator.)

With North American natural gas prices so low, it is difficult to justify any effort to displace gas completely, Mr. Malleck said. A rising federal carbon price will change that equation somewhat, especially for new buildings.

The Green Building Council’s Mr. Hutchinson defended the purchase of off-site renewable power to support the “zero carbon” performance certification, saying it supports a development market for low-carbon electricity. The practice does not provide the direct payback that onsite investments do, he noted, and is therefore used as a last resort.

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