Dans notre lutte contre les changements climatiques, les véhicules électriques font partie de la solution.
Driving electric vehicles (EVs) is a relatively new experience for Canadians, but they are becoming more popular. EV sales in Canada grew 68 percent from 2016 to 2017 alone, probably because they are cheaper to operate and maintain. There are now 50,000 on our roads.
Many Canadians also see going electric as a way to help reduce greenhouse gas (GHG) emissions and improve air quality. But there remains a considerable concern about the substantial environmental backpack, or burden, of manufacturing these vehicles. EVs’ enormous burden comes from the building of EV batteries, before the cars even hit the road. However, our comparison of the lifetime impact of EVs and conventional gasoline vehicles (GVs) shows that EVs charged from clean sources in Canada can pay off this environmental burden within three years, whereas GVs continue to add GHGs to the atmosphere for as long as they are driven.
Comparing environmental impacts
An environmental burden is associated with every commodity we produce or consume. The gold ring you presented to your loved one has one: it requires around 2,000 kilograms of materials removed from the earth to create a gold ring weighing a mere 5 grams. A cup of coffee isn’t innocent either; one cup (125 mL) requires 140 litres of water, among other inputs, to get to your taste buds.
To compare the environmental impacts of EVs and GVs, as measured in GHG emissions or their equivalent, we need to look at their entire life cycles. Figure 1 shows the components that must be assessed: what goes in and what comes out at every stage of the vehicle’s life, including recycling and disposal after use.
A lot of energy — much of it generated with fossil fuels — is needed to mine and transport the metals like lithium, cobalt, manganese, nickel and graphite that go into an EV’s battery. So EVs have a higher burden in the stages that lead up to putting them on the showroom floor, and a slightly greater impact than GVs in their end-of-life stage. But their emissions while in use are so much lower that, overall, they clearly provide the best way to decarbonize Canada’s transportation sector.
Electrification as a climate change solution
Transportation is a significant source of GHGs, producing 24 percent of total national emissions. Passenger and freight GVs account for a whopping 96 percent of transportation emissions. While Canada’s latest GHG figures submitted to the United Nations have started to show a downward trend, the decline is certainly not happening at the rate required to meet the country’s international commitments under the Paris climate agreement. We need to do more.
Use of EVs rather than GVs can curb overall GHG emissions from transportation — especially where the electricity used to charge them is generated from clean sources. Already, 72 percent of our electricity comes from renewable sources like hydro, wind and solar; in British Columbia, it’s 95 percent. That makes the case for promoting EV adoption in BC extraordinarily strong.
EVs can consume twice as much primary energy during the manufacturing process as GVs, creating double the emissions (figure 2). However, over their years of driving (10,000 km per year for 15 years), EVs such as the Nissan Leaf generate lower emissions: 99 percent lower in BC, where the electricity comes from clean sources, and even in Alberta, where a significant amount of coal is used to power the electrical grid, 50 percent lower.
Although the GV starts the driving stage of its life cycle with a lower environmental burden from manufacturing than an EV (figure 3), the GV generates more GHGs as it goes because it burns gasoline. By about 30,000 km, counting both the manufacturing burden and driving, an EV charged in BC has broken even: that is, these two cars have generated the same total GHG emissions so far. But after 30,000 km, the GV continues to emit GHGs while the EV charged in BC produces next to none for the rest of its driving years. An EV driven in Alberta breaks even with a GV within five years or about 50,000 km, and it produces significantly lower emissions than the GV after that. Drivers who choose EVs help to reduce Canada’s overall transportation emissions from the level they would reach if everyone continued to drive GVs.
Reducing the environmental burden by recycling
As EV sales grow, more batteries are built and will eventually reach their end of life. It is essential that recycling technology also develops to keep up with the fast growth of the market. We must be able to recover nearly all the construction materials, allowing us to displace raw material that would otherwise be mined.
The accomplishment of this vision of a circular economy for EVs will require additional research and planning over the next decade. It is a challenging task, but it can be achieved if there is a broad commitment from all stakeholders.
Nissan is already setting up a plant to reuse and recycle used lithium-ion batteries from EVs. In BC, Retriev Technology recovers 75 percent of the weight of the lithium-ion cells, primarily the cobalt, nickel and copper. Our analysis shows that to significantly reduce the end-of-life burden of EVs, recovery of all battery materials is essential; recycling facilities are sure to evolve to meet this benchmark.
Every product we enjoy carries an environmental burden. For Canadians who decide to buy a car, EVs are the better choice. When transportation is one of the largest sources of GHG emissions, electrifying the vehicles on Canada’s roads could be a formidable climate change solution.
Some provincial governments have policies that encourage consumers to buy EVs. In BC, the Clean Energy Vehicle program (CEVforBC) provides up to $5,000 toward an EV purchase. In Ontario, the Electric and Hydrogen Vehicle Incentive Program offers incentives up to $14,000 for EVs. Such policies will put Canada on the right road to decarbonization.
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