The idea that electric cars are a climate-friendly alternative is crumbling. While batteries have long been regarded as the electric car’s weak spot from a practical point of view, Swedish meta-research by specialist magazine Ingeniøren now suggests that they don’t actually do the environment any good either. The reason? The production of the all-important Lithium-Ion-batteries causes large emissions of harmful substances. It was already known that the need for rare resources used in electric cars has an important impact on the environment, but now it becomes clear that electric mobility itself isn’t that good for the environment either.

The new research shows that, for every Kilowatt-hour (kWh) of storage capacity in car batteries, around 150 to 200 kilogramme of carbon dioxide equivalent is produced. With the two most commonly sold electric cars in Denmark, the Nissan Leaf and Tesla Model S, equipped with 30 kWh and 100 kWh batteries, this means an emission of 5,3 and 17,5 ton of CO2 respectively. These are immense numbers, as the study’s comparisons show. For example, a return flight from Stockholm to New York, according to the UN’s Internation Civil Aviation Organisation (ICAO), causes 600 Kilogramme CO2 to be blown into the atmosphere. Meanwhile, the CO2 emission in Germany per head of the population is nearly ten ton each year.

New calculations show, that a vehicle using fossil fuel can drive for over eight years, before it has the same environmental impact as a Tesla. For the Nissan Leaf, the figure is almost three years. ‘Unnecessarily large batteries negatively impact the environment even more. One should, therefore, try to see if smaller batteries would be enough,’ one of the writers of the new study, Mia Romare, posits.

Processing of raw materials and the factory production of batteries accounts for about 80% of the total environmental impact. Only about 10 to 20% is caused by mining the raw materials, according to Ingeniøren.