Getting greenhouse gas emissions under control

25 April, 2013, Vanessa Santilli

It is possible for a Canadian city to reduce greenhouse gas emissions 71 per cent by 2031, found a recent study published in the The Canadian Journal of Civil Engineering.

Using a case study of Toronto, researchers at the University of Toronto outlined the necessary measures — such as increased use of electric cars and overhauling existing heating and cooling systems — required for reducing greenhouse gas emissions by the sort of levels the international scientific community have indicated is key to keeping global temperature rise below 2°C.

“Cities are responsible for a large amount of the emissions so that’s why it’s important to show how a city can reduce its emissions,” said study co-author Chris Kennedy, a civil engineering professor at the University of Toronto.

The study — which focuses on buildings, energy supply and transportation — arose out a of a handbook Kennedy and his students produced for the Toronto and Region Conservation Authority in 2010, Getting to Carbon Neutral: A Guide for Canadian Municipalities. The paper is co-authored by Lorraine Sugar, World Bank climate change specialist and one of Kennedy’s former students

Under the city’s planned policies, a 31 per cent reduction in per capita greenhouse gas emissions is estimated, with most of the savings due to reduced electrical emissions intensity under Ontario’s Integrated Systems Plan as well as a reduction in internal combustion automobile use.

“Based on our knowledge and experience of what other technologies we knew were ‘heavy hitters’ in a sense — which we knew could make big differences — those were the ones that we chose to add to what the city was already considering,” said Kennedy.

In terms of heating homes and businesses, most Torontonians use natural gas from furnaces. While this is better than burning coal, it still has greenhouse gas emissions associated with it, said Kennedy.

To get to the “next level” in the energy sector, the paper calls for a heating and cooling technology called underground thermal energy storage. The premise is that we have enough heat to heat our homes, but it arrives at the wrong time of year, said Kennedy.

“If you look over the course of the year, we’ve got all this sun in the summer that makes our homes too hot when we want to cool them and then in the winter it’s the converse…So the trick with underground thermal energy storage is you take the heat from the summer, you store it underground….and then you withdraw the heat when you need it in the winter.
He said this is not farfetched idea.

“There’s a community called Okotoks in Alberta where they’ve established a large scale one in tandem with using advanced low energy buildings,” says Kennedy. “They have managed to reduce heating requirements relative to a base case conventional buildings with reductions of up to 90 per cent.”

At what cost?

However, as with any newer technology, there are higher costs associated with this.

“It’s still expensive in many places but I think there’s enough learning going on and enough systems being built that it could be a real game changer in terms of heating and cooling of buildings.”

Increasing the number of electric cars on the road will also make a big difference, found the study.

“Public transit is not the solution to climate change. You can’t take everyone out of cars and put them on subways and buses…It leads to the fact that the automobile is here to stay and you need to begin to reduce the carbon emissions associated with it.”

Some of the many other suggestions in the paper include: increasing usage of solar water heaters, retrofitting residential homes and high-rise apartments, banning incandescent bulbs, requiring energy-efficient appliances and increasing parking prices to deter auto use.

The aggressive alternatives being proposed are realistic as they are looking at long-term horizons, said Kennedy. “We’re looking at something that is a decade or more away.”

Many of the different technologies proposed in the study have been around for a long time, said Neal Scott, Canada Research Chair in Greenhouse Gas Dynamics and Ecosystem Management.

“The technology isn’t going to take off and become part of our society if people don’t want them,” he says, citing the example of electric cars. This is because they have remained too expensive when having to compete against less expensive petroleum products, he says.

The paper points to a lot of different things we can do to reduce greenhouse gas emissions — but will we get to the 70 per cent reduced projection by 2031?

“I think there’s something else that needs to change other than just having the technology out there…Public support or government support or both. It needs to be a priority.

“We don’t have a carbon tax. We don’t have a carbon crediting system. Canada has stayed away from those tools that are being put up as ways of trying to put a cost on greenhouse gas emissions or put a benefit on reducing emissions.”

(Santilli is a freelance writer based in Toronto.)

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