The regulator is consulting on plans that aim to reduce the cost to consumers of meeting the extra demand from EVs as well as connect more renewable generation, battery storage and other technologies to the grid.
It believes if owners use flexible charging – where they only top up outside peak demand times on the grid – at least 60% more EVs could be charged up compared to when they are only charged at peak times.
Ofgem suggests flexible charging would allow EVs to be charged up when energy prices are the cheapest, for example when solar panels and wind turbines are generating a lot of electricity or when there is less demand on the system.
It adds energy costs could also be reduced for consumers as technology allows stored power from EVs to be sent back to the grid when needed.
The number of EVs on UK roads has grown from less than 4,000 in 2013 to around 160,000 as of June 2018.
National Grid recently said it could reach as many as 11 million by 2030 and 36 million by 2040.
Ofgem has set out the reforms as it believes the current approaches to allocating and using capacity – and charging for the associated network usage – on electricity networks cannot make the most of opportunities and adequately address the associated challenges.
It intends to work with industry to overhaul energy system rules and put the reforms in place between 2022 and 2023.
Jonathan Brearley, Executive Director, Systems and Networks said: “Ofgem is working with government to support the electric vehicle revolution in Britain which can bring big benefits to consumers. Our reforms will help more users charge their electric vehicles and save them money.
“The proposals we have announced today will also harness the benefits of electric vehicles and other new technologies to help manage the energy system and keep costs down for all consumers.”
It is seeking views until 18th September 2018.