EVs. Clean, sure, but not quite as much as you think, scientists found

EVs. Clean, sure, but not quite as much as you think, scientists found

Electric, hybrid and other eco-friendly cars kick out as many toxins as diesel vehicles, according to scientists who say greener vehicles produce more tiny particles from tyre and brake wear because their batteries make them heavier.

Under acceleration and braking, tyres and brakes wear faster so producing more particulates while more particles are also whipped up from the road surface because of the extra weight. 

This is according to research, led by Peter Achten and co-author Victor Timmers of Edinburgh University, and published in the journal Atmospheric Environment. Achten told the Sunday Times: "We found that non-exhaust emissions, from brakes, tyres and the road, are far larger than exhaust emissions in all modern cars.

"These are more toxic than emissions from modern engines so they are likely to be key factors in the extra heart attacks, strokes and asthma attacks seen when air pollution levels surge."

The research used technical data from the motor industry and government research agencies, including direct tests of brake, tyre and road wear rates. The aim was to show that non-exhaust emissions  are directly related to a vehicle's weight.

The research discovered that electric and eco-friendly cars weighed around 24% more than conventional vehicles, a discovery that linked to anecdotal complaints from 'greener' car owners that their tyres wear out faster.

The University of Hertfordshire in the UK also studied the impact of non-exhaust emissions and, after installing particulate air pollution monitors in the southbound Hatfield tunnel on the A1(M), through which 49,000 vehicles a day travel, scientists found each one produced 34-39 micrograms of particles per kilometre -but only a third came from the engine.

Other pollutants included small pieces of bitumen whipped up from the road, rubber from tyres and brake dust.