In a few years, EVs will be taking to UK roads in much greater numbers than they are today. But will the UK’s electricity-generating network be able to keep up?
Although there has been widespread concern that it won’t, the current assessment by National Grid plc (which also manages the UK’s natural gas supply) is far more optimistic. If the right steps are taken, then far from overloading the network, EVs could actually contribute to reducing energy consumption by 2050.
Thanks partly to the 2019 Climate Change Act, which aims for net zero CO2 emissions by 2050 across the board, energy supply for EVs will form part of a massive UK decarbonisation strategy. In its annual Future Energy Scenarios report (FES), National Grid lists four possible ways in which the UK’s energy model will shape up. Two of those will achieve net zero emissions by 2050.
National Grid’s electricity network is split into two main parts: the high-voltage three-phase network and the local, low-voltage single-phase networks, carrying electricity from substations to properties.
National Grid says those sites can be linked cost effectively to the high-voltage transmission network directly. It also recommends that this happens before price parity with petrol and diesel cars is reached in around 2025, to avoid range anxiety being a barrier to EV uptake. It warns that this will work only with government intervention under the AEV Act, saying that a market-led approach would lead to a postcode lottery.
UK consultancy Capital Economics forecasts that to meet 2050’s ‘net zero’ targets, the UK will need: 25 million EV charging points, 22 million home heat pumps, and £240 billion total outlay.
Making the most of what’s there
A rapid-charging project called DC Share is under way with Western Power Distribution, Electricity North West and Ricardo. Its aim is to boost the capability of local networks to power rapid chargers.
Although local AC distribution networks can be protected from mass EV plug-in at peak times by smart charging, that doesn’t allow for attaching power-hungry rapid charger clusters to the same networks. For that, expensive ‘network reinforcement’ may be needed, such as increasing the capacity of transformers, overhead lines and cables.
The DC Share project will tap into surrounding networks, drawing unused power to drive rapid-charging hubs. The project will lay a DC equalisation cable network between transformers, so those experiencing heavy demand can be supported by others that are lightly loaded.
If successful, this approach would be cheaper and more efficient than implementing the usual network upgrades and enable greater numbers of rapid chargers without the need to generate extra power.