01/20/2014 09:41 EST | Updated 03/22/2014 05:59 EDT

Environmental impact of electric cars still up for debate

Lukas Swan is a professor of mechanical engineering at Dalhousie University who not only studies electric cars, he also drives one.

Swan says with a single charge, his Nissan Leaf has a maximum range of about 150 kilometres, and adds that a round trip to work boosts his electricity bill by about $2, compared to the $10 he'd have to pay at the pump.

Despite the cost savings, the environmental impact of electric cars is still being debated. A study published by the Wall Street Journal last year found that the majority of the emissions produced by electric cars - 30,000 pounds of carbon dioxide - are created before the cars even hit the road. The same article also said it takes about twice as much energy to make an electric car as a traditional gasoline model.

Jeff Dahn is a professor of engineering and chemistry at Dalhousie, he says the production of batteries for electric cars still produces fewer carbon-dioxide emissions compared to the greenhouse gases generated over the lifetime of a conventional car.

But with more studies being done all the time, it's easy to find a dissenting opinion. Larry Hughes teaches electrical engineering at Dalhousie, he says electric cars only make sense in some parts of Canada.

"It depends entirely upon the energy mix of your electricity provider," he says. "If your electricity provider is coal for example or lignite as is the case in Saskatchewan or anything with a high carbon content, what you are going to find is indirect CO2 emissions from an electric vehicle are probably close to those of a conventional vehicle."

Swan agrees that power sources makes a difference, but he says even in province's with dirtier electricity production, such as Alberta, Nova Scotia and Saskatchewan, electric cars still edge out the competition. He says the push for more renewable sources of power means cars like the Nissan Leaf will only become more efficient as time goes on.

But even Swan admits the electric car has some limitations, he says it's not ideal for longer trips that go beyond the single charge range. Which is why the second vehicle in his driveway is a gas model, Honda pickup truck.