THE IDEA that all cars in Britain should be fully electric by 2040, a relatively short space of time for developing a huge and expensive national infrastructure, is so silly and potentially damaging that it is hard to know where to start criticising it. That Ms Sturgeon would like to see it achieved in Scotland eight years sooner is even more absurd. But let us start with the most serious flaw; where is the electricity to run them to come from?
In the UK the transport sector currently consumes about one third of total energy demand. Not all of this is due to cars, and electric vehicles can in principle be more efficient than internal combustion engine vehicles, however one estimate suggests that if all Britain's cars were electric, electricity production would have to increase by more than one third, from 337 TWh (terawatt hours) a year to 460 TWh. If this were to be supplied by nuclear power stations this would mean more than 18GW (gigawatts) of new capacity. Another estimate produced by National Grid suggests we may need as much as 30GW. Right now we have plans for only one new nuclear power station, Hinkley C, with a capacity of 3.2GW at a cost of at least £20 billion. So we would be looking at between five and ten more Hinkleys at £100-£200 billion. That estimate demonstrates the potential cost and scale of what could be required to make the proposal viable.
We could of course put up more wind turbines to generate this electricity, however, while a nuclear power station can run at 90% of its rated capacity over the year, wind turbines can only manage about 30%, so we would need 48GW, requiring 16,000 new wind turbines, another four times the current number. These would occupy about 19,000 square kilometers, equivalent to more than a quarter of the area of Scotland. In addition, wind turbines need a back-up for when the wind is too fast or non-existent, as any extended failure in supply would mean the UK losing all of its transport systems, so we shall still require matching nuclear, gas or coal power stations in any case.
Our electricity supply system is already creaking, with the closure of coal-fired stations the National Grid has been paying up to £2000 per MWh in emergency backup from diesel generators, about fifty times the normal wholesale cost. It would seem irresponsible to propose increasing electricity demand until we are sure that current demand can be securely and economically fulfilled. It also makes little sense to use diesel generation as back up when the purpose of adopting electric cars is ostensibly to reduce air pollution – which is why nuclear makes sense.
Then there is the logistics of charging all these cars. To refuel a petrol or diesel vehicle takes less than five minutes to fill a nearly empty tank. Filling stations are now being equipped with 'fast' chargers for electric cars. These take about 30 minutes to provide an 80% charge, so we could be looking at rather longer queues. If you are able to park off road at home then your domestic supply can do the job overnight in about eight hours. But what if, like many city residents, you have to park on the street? It would be possible to install charge points along city streets, but at a cost since the electricity network was not designed with this in mind. The cost of upgrading both the local and national networks is likely to be very significant, and no estimates seem to have been made of it. In Scotland the difficulty and costs would be exacerbated due to having many more isolated settlements and city centre tenement flats.
Indeed what will it all cost? An electric car put on the road today enjoys a straight grant of £4,500 from the taxpayer towards the cost of the car and the remission of road tax of typically £200 a year over its life. Instead of excise duty and VAT at £2.63 per gallon plus VAT at 20%, electricity carries only VAT at 5%. The annual loss of tax revenue for a car doing 10,000 miles a year would be nearly £1,000. Over an expected vehicle lifetime of 14 years taxpayers are generously giving electric car purchasers more than £18,000. If the same generosity were extended to the owners of nearly 30 million cars the bill would come to half a trillion pounds.
Obviously that would be unaffordable to any government therefore we would likely see the subsidy to electric cars removed and a levy placed on either fuel or the cars themselves (or both) to replace the lost fuel duty. These responses would act as disincentives to purchasing an electric car and so the question then becomes how do you make a smooth economic switchover when cars cannot be replaced altogether overnight?
Until the issues of power generation, logistics and cost are resolved all cars being electric looks unachievable and unaffordable – be it Scotland or the UK.
Jack Ponton FREng, Emeritus Professor of Engineering and a member of Scientific Alliance Scotland.