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Ecometrica analysis pegs average UK EV emissions at 75 gCO2/km; varies by country

The average emissions for an electric vehicle in the UK are 75 gCO2/km, when CO2 emissions at the power station are taken into account, according to an analysis by Gary Davis, Operations Director and chief greenhouse gas (GHG) analyst at Edinburgh-based carbon accounting firm Ecometrica.

This is lower than any other car in production, including the Toyota Prius (89 gCO2/km) and the VW Golf Bluemotion (99 gCO2/km) – two of the previously best-performing low-emission vehicles.

However, this figure is only correct for the UK, the company notes, as electric vehicle emissions calculated in this way are dependent on the electricity grid mixture of the specific country. Davis also calculated average emissions for France, Greece, the US, Canada and China. (see figure below).

Electric car emissions by country charted against modern diesel and gasoline cars. Click to enlarge.

Methodology. Davis firstly calculated electric car efficiency based on manufacturers’ range and battery capacity data for three electric cars; the Nissan Leaf, the Mitsubishi i-Miev and the Renault Fluenz.

He then took government data on the UK grid carbon intensity and applied this to the electric car efficiency. The grid carbon intensity calculations included not only the energy losses at the power station, but also the energy losses for transmission and distribution of the electricity across the UK electric grid.



Good to see an attempt at quantifying this type of situation. Every time an article on EVs appears here in the Aussie press the comments are always flooded by people using the "but coal-fired power is much worse" line. Coal certainly isn't ideal but it's better than oil.


EV pollutions would vary a lot in Canada from one Province to another. EVs operated in Manitoba and Quebec would be close to zero gCO2/Km while it could be much higher in Alberta and many other provinces.


Methodology is not correct. The EV uses marginal electricity (coal or gas) and not grid average. So the CO2 level is a lot higher than this.

UK minimum electricity demand is 24 GW. Max zero CO2 (wind, hydro, biomass, nuclear) is around 14 GW. So the extra electricity always comes from coal and gas. This is much higher than the average.


"Extra" electricity in the western U.S. comes from natural gas turbine peak plants to run air conditioners in the summer afternoons.

If the EV is charged at night, there is extra capacity from base load plants. Some is hydro, nuclear, natural gas and even coal. I would say an EV charging at night would be cleaner in California than a regular car, that was the idea behind ZEV.

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