Well this is disappointing. New research that examined the life-cycle impact of conventional and electric vehicles shows that in many cases electric cars might pollute much more than petrol or diesel-powered cars. So if you are looking to buy an electric car to save the planet, you could, in fact, be harming it.

The Norwegian University of Science and Technology study found greenhouse gas emissions rose dramatically if coal was used to produce the electricity, and electric car factories also emitted more toxic waste than conventional car factories.

By studying the life-cycle impact the researchers considered how the creation, use and the end-of-life dismantling of a car affects the environment. Co-author Prof Anders Hammer Stromman explains:

The production phase of electric vehicles proved substantially more environmentally intensive . . . [and] the global warming potential from electric vehicle production is about twice that of conventional vehicles.

On top of this, the batteries and electric motors needed for electric cars require a lot of toxic minerals such as nickel, copper and aluminium to produce which means the acidification impact is much greater than that of conventional car production.

Across the other impacts considered in the analysis including potential for effects related to acid rain, airborne particulate matter, smog, human toxicity, ecosystem toxicity and depletion of fossil fuel and mineral resources, electric vehicles consistently perform worse or on par with modern internal combustion engine vehicles, despite virtually zero direct emissions during operation.

[a]ssuming a vehicle lifetime of 200,000km exaggerates the global warming benefits of electric vehicles to 27-29% relative to petrol and 17-20% relative to diesel.

If you are considering purchasing an electric vehicle for its environmental benefits, first check your electricity source and second look closely at the warranty on the batteries.