A UK based organisation has looked at the CO2 emissions of EVs.
Scientists from the universities of Exeter, Nijmegen and Cambridge conducted lifecycle assessments of both the electric-vehicle market and household heating, two of the biggest markets for electric power draw, which showed that even where electricity generation still involves substantial amounts of fossil fuels, there was a CO2 saving over conventional cars and fossil-fuel heating. Their findings were published in the journal Nature Sustainability.
They found that in 53 out of 59 regions, comprising 95% of the world, electric vehicles and domestic-heat pumps generate less carbon dioxide than fossil fuel-powered cars or boilers. The only exceptions are heavily coal-dependent countries such as Poland.