The vast majority of electric car owners charge their vehicles at home in the evening or at night. A new study from Stanford University warns that this could lead to electrical grid overload in the near future.
The study shows that the vast majority of electric vehicle owners charge their cars at home in the evening or at night, which can overload the power grid. The study recommends that electric vehicle owners charge their vehicles at work or at public charging stations throughout the day.
The study, published in the journal Nature Energy, examined the pressure from increasing numbers of electric vehicles on the power grid in the western United States by 2035. The result: If the rapid growth of electric vehicles continues and the habit of charging at home at night continues, peak electricity demand could increase by 25% in a little over a decade.
Charging habits are changing
If most EVs continue to charge overnight, the state of California will have to build more generators, possibly natural gas, or invest heavily in expensive energy storage. If more people shift their charging habits to work or public charging stations during the day, greenhouse gas emissions will be reduced and additional costs for electricity generation and storage are avoided.
One of the problems is that commercial and industrial customers of energy suppliers have to pay high rates based on their peak electricity consumption, which can deter employers from installing chargers, especially when half or more of their employees drive electric cars.
“We encourage policymakers to consider utilities rates that encourage investment in charging infrastructure and daytime charging so people can charge their cars more at work,” said study co-author Ram Rajagopal. Currently, California still has a surplus of electricity late in the morning and early in the afternoon, mainly due to its solar capacity.
Also in Belgium
The threat of power grid overburden due to charging electric cars is not only a problem in California, but also in Belgium. In February, energy regulator VREG proposed a set of policy measures that will have a reducing effect on future grid load. For example, it includes encouraging slower charging of low-voltage electric vehicles. In the future – “towards 2050” – the low voltage grid will need to be strengthened in many places to avoid overloading.
A few years ago, industry body Synergrid said that the Belgian electricity grid could "take growth in the electric vehicle fleet, provided that the charging of the vehicles is phased out". “If everyone gets home from work and unplugs the car at the same time, there's a problem.”