There has been growing support for electric vehicles in many countries including Canada. Many governments have given sizeable subsidies to electric car buyers to help lower the price of electric vehicles and therefore increase demand.

One of the major justifications for government subsidies is that electric vehicles will reduce greenhouse gas emissions. However, according to new research published by Bloomberg, emissions may actually increase depending on the source of energy used in battery manufacturing.

What’s often misunderstood about electric cars is that the lithium-ion batteries need for these cars are manufactured in some of the world’s worst-polluting countries. More specifically, by 2021, most of the battery components for electric vehicles will come from countries such as China, Thailand, Germany and Poland, each of which relies on non-renewable energy sources such as coal for electricity. As a result, while electric cars are emission-free on the road, the process of building the batteries may discharge a significant amount of carbon dioxide.

According to the sources presented in the research, building a car battery for a sport-utility vehicle (1,100 pounds) could emit up to 74 per cent more CO2 than producing an efficient conventional gas-powered car, assuming the battery is manufactured in a factory powered by fossil fuels such as coal. The specific amount of additional CO2 from electric vehicles is dependent on where the battery is made, how it’s made, and the sources of electricity.

Simply put, drivers in countries heavily dependent on non-renewable powered electricity generation might release more CO2 emissions with electric cars compared to an efficient diesel engine. For instance, in Germany an electric vehicle would take more than 10 years to break even (with respect to its CO2 emissions) compared to an efficient vehicle’s combustion engine.

In reality, the environmental benefits of electric vehicles may not be realized if the electricity used to build the vehicle’s battery comes primarily from non-renewable sources.