The International Energy Agency made the prediction in its World Energy Outlook 2017:
Electricity makes inroads in supplying heat and mobility, alongside growth in its traditional domains, allowing its share of final consumption to rise to nearly a quarter. A strengthening tide of industry initiatives and policy support pushes our projection for the global electric car fleet up to 280 million by 2040, from 2 million today.
The prediction is little more than a guess. Even leading experts in energy cannot say what will happen to fossil fuel prices or the appetite for electric cars. If the forecast is right though, car manufacturers will need to retool for a massive rotation in the products they produce as consumers become willing to give up on the kind of engines that have driven cars for over a century.
Another byproduct of the move to electric vehicles — and industries that use fossil fuels today but will move to electric-powered means of production — is that the demand for fossil fuels will dissipate. Some experts believe that the amount of oil producers can pump will have dropped sharply by then anyway because fields, both those that pump oil now and those discovered in the near future, will trigger a period in which oil production across the world will begin to fall.
Will there be 280 million electric vehicles on the world’s roads by 2040? It is anyone’s guess.