It’ll take more than just driving an electric vehicle to save the environment. You’ll have to charge them at the right time, too.
Put simply, if the world’s drivers plug in an increasingly large EV fleet right after work, it could undo many of the environmental benefits expected from fewer cars running on gasoline and diesel. Cutting pollution could come down to an act as unexceptional as waiting until bedtime to charge the minivan.
Down one path lies a future world with cleaner skies, cheaper energy and more reliable electricity systems. The other has more fossil fuel-burning generators, higher power prices and additional strain on the grids keeping lights on everywhere from hospitals to schools.
“The key question isn’t how much demand electric vehicles add to the grid, it’s when does it add it,” said Daniel Brenden, a senior power and renewables analyst at BMI Research in London. “EVs are either going to be huge problem or a huge tool.”
Sales of electric passenger vehicles surpassed 1 million for the first time in 2017. Forecasts for future growth vary wildly: Exxon Mobil Corp. expects the global fleet to swell to 100 million vehicles by 2040, while Bloomberg New Energy Finance sees it reaching 540 million units by then, with more than half of all cars sold being powered by electricity.
Even at the high end of estimates, global electricity production would need to increase by just 5 percent to meet the new vehicle demand, said Colin McKerracher, an analyst with Bloomberg New Energy Finance. The new generation may not even require new power plants if grid operators, regulators and drivers can get on the same page as far as timing goes, McKerracher said.
That’s because of the unique structure of the power market, in which demand ebbs and flows minute-by-minute during the day as people flick their lights and appliances on and off. Consumption typically peaks in the evening and morning, and is at its lowest in the middle of the night.
If drivers plug in their cars when they get home from work and add to that evening peak, even the modest amounts of new generation needed will likely require building more capacity, and that likely will have to be in the form of fossil fuel-fired plants, Brenden said. And because the owners of those plants will have to pay down debt while only operating a short time of the day, their rates will have to be higher.
“You’re not contributing to decarbonization as much as you’d like, and you’re paying to keep that backup generation ready, so you’re adding to your electric bill,” Brenden said.