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Urban sustainability is the next frontier of city building

Urban farm at Ryerson's George Vari building

Humans place an incredible strain on the natural environment. Carbon dioxide from vehicle exhausts and building construction contribute heavily to climate change, single-use plastics and other garbage collected in landfills — even road salt is hurting our rivers, lakes and waterways.

If we are to mount a serious defence against climate change, our cities will need to find ways to be ecologically sustainable by reducing emissions and waste. From urban farming to carbon neutral housing, Ryerson is taking the lead on ways to make our everyday activities better for tomorrow’s environment.

Interior of Ryerson ZeroHouse

A place to call home

Every one of the 100,000 people who move to Toronto each year needs a place to live. Unfortunately, the vast majority of new units are prohibitively expensive and many are located in conventional high-rises that are polluting to build.

Architect and researcher Cheryl Atkinson and her student team have designed an answer — a low-carbon house that meets the needs of a growing city and an increasingly fragile environment. The project emerged from a research team put together by professor of engineering Alan Fung and professor of entrepreneurship and strategy, Philip Walsh to address sustainable urban housing.

"High-rises are made of concrete where they burn lime that produces a huge amount of carbon, and same thing with steel," says Atkinson. "Not only is the construction cost very high, but so is the environmental cost."

Their ZEROhouse concept is a stacked townhouse designed to be built on cheap land formerly occupied by one or two-storey buildings — gas stations and other low-density structures — in existing neighbourhoods.

"It's got a very high-quality, contemporary aesthetic. It's not a crunchy granola house ... we tried to make a feature out of the extra thick walls and give it clean minimalist lines and details so that it would look architectural and cool."

Cheryl Atkinson

The 1,100-square-foot, wood-framed structure is made of eco-friendly materials such as straw bale and wood fibre insulation. The floor is made from ash trees cut down due to emerald ash borer infestation and the exterior is covered in peel-and-stick materials that turn solar energy into usable electricity.

Most importantly, the ZEROhouse is modular, meaning it can be built in a factory and shipped to the construction site in parts for assembly. A prototype built in 2017 is now being lived in permanently in Clarksburg, Ont. The Ryerson team are studying its performance while working on marketing the concept to construction companies.

"Buildings, residential and commercial, are next to transportation as the largest contributor to greenhouse gas emissions in our province," says Walsh. "So what we’re looking at is trying to design acceptable solutions to deal with that."

Humber Bay Arch Bridge in Toronto

Photo by Taxiarchos228 via the Wikimedia Commons

Protecting our waterways

Water is Canada's most precious natural resource, but every year our rivers, lakes and streams bear the brunt of thousands of tons of rock salt used to de-ice our cities in winter.

There are several toxic ingredients in road salt, but chloride is the worst offender, says Claire Oswald, professor in the Department of Geography and Environmental Studies. Her work focuses on the ways salt enters and contaminates our waterways.

"Chloride at high concentrations is actually toxic to freshwater organisms and it can cause problems for vegetation and the quality of soil," she says. "It also corrodes bridges, eats concrete and rapidly degrades important urban infrastructure."

The solution, she says, is brine — a 23 per cent salt–water mix that prevents snow and ice from sticking to surfaces when it's sprayed prior to a winter storm. It also helps melt what does freeze to the ground.

Working with Ryerson's Facilities Management and Development, Oswald is conducting a pilot study that the World Wildlife Fund and several small municipalities are watching with interest. It compares brine with regular rock salt in zones across the Ryerson campus. The university's facilities department invested in a $10,000 brine applicator and at the end of the season spatial analysis student Kevin Duffin will examine the results with an eye to scaling it up — "to a portion of the city, or even to the entire city," Oswald says.

"We're working on the institutional support for the whole thing and educating everybody at Ryerson about this project and the role [it] can take in moving towards a less salty city."

Ryerson University energy container

Storing green energy

As more and more people move to cities, they will need urban energy solutions that are affordable, reliable and sustainable.

Jessie Ma, IESO research fellow at Ryerson’s Centre for Urban Energy, is studying the economics of storing energy within the electrical grid to reduce emissions and waste.

"Energy storage can work with intermittent renewable energy, such as wind or solar, so that energy from those sources can be available when it's no longer windy or sunny," she says.

Storing energy can also reduce stress on the grid when there’s a sudden spike in demand — for example if a large number of electric vehicles begin charging in a small area — and reduce capital costs for utility companies.

Without storage, power generating stations must carefully balance electricity production with the up-to-the-minute demands on the power grid. Make too much and it goes to waste, too little and it will lead to shortages.

Ma’s work is ongoing, but the overall goal is to make electricity more environmentally friendly to generate and cheaper for consumers to buy.

"The ideal city will be powered by affordable, reliable and clean energy, enabling its citizens to lead healthy, vibrant and fulfilling lives," she says.


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