Which is all very well, but how will we be charging our EVs? Aside from the challenge of having enough charging spaces for hundreds of thousands of new EVs every year, there’s the pressing issue of the strains on the electricity transmission network. On top of that, there’s the question of how the electricity is being generated.
As I write this on a blustery afternoon in the UK, the national grid live monitor shows an impressive low-carbon performance. With demand at 34.5GW, the remaining UK coal stations are off, gas is producing 28.6% of the electricity, nuclear 23.7%, wind nearly 22% and solar 11%. That’s nearly one-third renewable and over half of the generation is ‘low carbon’.
A bright and blustery day is ideal for showing the potential of renewable energy, but critics are probably right to say ‘renewable’ also means ‘intermittent’. What happens in winter, when demand is higher and the days shorter? And what happens on a still winter night when large numbers of EVs are trying to charge up?
The challenge of charging a big EV fleet is going to be significantly more difficult in the UK because of plans to decarbonise its power generation network. According to the Climate Change Committee, a governmental agency, the UK is planning to totally transform the way its electricity is generated.
The UK is legally bound to generate 30% of its electricity by renewables by 2020. The target is for electricity generation to be almost totally carbon-free by 2050, so the UK’s electricity feed will come increasingly from renewables over the next decade. That’s another reason why having large numbers of batterypowered cars is necessary: when the wind blows and the sun shines, that energy needs to be soaked up by batteries and EVs will be ideal to do that.
If that’s not a big enough hurdle for the EV revolution, there’s the issue of strain on the network. One pressure group — the Green Alliance — has said clusters of recharging EVs could cause voltage drops locally, potentially damaging electric equipment. Even government ministers have publicly warned of the effects of EV owners all plugging in during the early evening. Electricity providers are talking of the need to spend significant sums on upgrading the network to take the extra loads.
The real solution, claims James O’Neil of Finnish company Ensto, is insisting that all car chargers installed from now on are smart chargers. Yes, he might well say that because that’s what his company makes, but he’s also right.
“While it’s being charged, an electric car will consume the same amount of power as a whole house will over 48 hours or even longer,” he said. Such loads will stress local networks, especially during evenings.
Ensto’s Chago chargers are connected to the web and use data streamed from the cloud to manage charging across a local area. But in the future, vehicleto-grid communication can use driving and parking patterns and even pre-selected sat-nav information to decide when and for how long individual vehicles are charged from the network. Such grid communication will be essential in the UK, especially given the 2040 plan.
To further even out power demand, O’Neil has also suggested these smart chargers be fitted in shopping areas and supermarket car parks. He said: “Regular charging throughout the day — including at workplaces — will also spread the load on the grid. Which is why fitting smart chargers is the only way to achieve genuine dynamic load management.”