Electricity for electric vehicles, year by year

How the figures are counted

The figures here are counted, and that is unusual for electric-vehicle demand. Most published estimates start from the number of cars on the road, multiply by an assumed annual mileage and an assumed consumption per kilometre, and arrive at a total. Each assumption carries its own error, and the three compound. Eurostat's energy balance instead adds up the electricity that suppliers delivered to road transport, the same accounting exercise that produces a country's figures for coal, gas and oil.

An energy balance is the annual ledger every EU member state files: how much of each fuel entered the country, what was transformed into something else, and what each sector finally consumed. Road transport is one of those final sectors. Final electricity use, the denominator of the share on this page, is what every sector together took from the grid, after the losses in generation and the network have already been taken out.

Read the two charts as a level and a proportion. The number view answers how much electricity charging draws in a year. The share view answers how much of the country's electricity that is, which is the question behind most headlines about electric cars straining the grid. The German and EU27 lines are worth comparing: Germany registers more electric cars than most member states, so its share sits above the EU average, and both rise from a base close to zero.

The energy balance publishes with a lag of about two years, so the most recent year here is behind the latest car registrations, and the gap between the two is a timing artefact. A year's total says nothing about the hour it arrives in: a fleet that charges overnight and one that charges at the evening peak produce the same annual figure and very different problems for the grid. Residual Load shows the hour-by-hour picture.