Making motoring more efficient is the title of a report published this week by Cambridge Econometrics. Commissioned by the European Climate foundation, this follows Fuelling Europe’s Future, published in September last year. Both studies look at the projected effects of moving to a lower-carbon, more efficient vehicle fleet between now and 2030.
The conclusions are, as expected, very positive. Motorists would save on fuel, demand for imported oil would reduce, jobs would be created and air pollution (a continuing problem in cities) would be reduced. However, if you subscribe to the view that he who pays the piper calls the tune, then this is simply another Mandy Rice-Davies moment; they would say that, wouldn’t they? On the other hand, Cambridge Econometrics is a well-established, professional consulting firm, so it would be foolish not to delve further.
The first point is that it is, of course, a good thing to have cars which are more economical to drive. Motoring technology has evolved surprisingly fast when we consider how mature the internal combustion engine is, and many mainstream cars today have the performance of sports cars of only a few decades ago coupled with fuel efficiency previous generations of drivers would have found unbelievable. And all this is due to skilled engineers and evolution of technology.
Judging by the continuing increases in fuel economy, this process still has some way to go. The mode of operation can also be important, at least in urban areas. To quote from the report: “Start-stop technology, using advanced lead-based batteries, is one of the most cost-effective ways to cut CO2 emissions in the range of 5-10%.” Policymakers may focus on emissions reduction, but for drivers the reduced fuel consumption is the more important factor.
Even without further improvement, the overall efficiency of the vehicle fleet will continue to increase for some years as older vehicles are scrapped and replaced by newer ones. But the issue at the heart of the study is the role played by developments other than more evolved petrol and diesel engines, that is by fully electric and hybrid vehicles.
The other potential new technology is the fuel cell, turning hydrogen, or possibly methanol, into electricity. A decade ago, there were plenty of people still suggesting that this could provide the motive power of the future. However, in the meantime, a combination of only modest gains in efficiency, the severe practical problems of generating and storing hydrogen and significant improvements in battery technology mean that we rarely hear about the hydrogen economy today. Fuel cells may have their day, but not for the foreseeable future.
In 2014, nearly 2.5 million new cars were registered in the UK, according to figures from the Society of Motor Manufacturers and Traders. Of these, 6,697 were fully electric cars. A total of 45,033 hybrid cars of various description were sold over the same period, the vast majority (34,494) being petrol/electric. Rather more plug-in hybrids were sold (nearly 8,000) than fully electric cars.
Sales of hybrid and electric cars increased substantially over the year, by 166% for fully electric vehicles and 32.6% for petrol/electric hybrids (not plug-in), against a roughly 9% rise in car sales overall. However, to put that in perspective, that’s still only about 0.26% of the total market taken by electric cars and 1.8% by total hybrids.
For comparison, the central projection from Cambridge Econometrics is for plug-in electric vehicles (which from their figures appears to include plug-in hybrids) rising to 2% of the market by 2020 and 10% by 2030. They also project hybrid sales to account for 20% of new registrations by 2020 and 40% by 2030. There may be an element of double-counting in these figures if the ‘plug-in’ figure includes hybrids but, in any case, these projections seem optimistic.
First, consider that hybrid vehicles are sold at a premium because of the additional costs imposed by adding batteries, electric motors and control systems. This additional cost rises steeply for plug-in hybrids (with greater battery power) and fully electric cars, which is why the government provides a subsidy of £5,000 for their purchase.
The additional cost may be justifiable if fuel costs are lower, but overall fuel economy is no better for current hybrids than the latest generation of highly-efficient conventionally powered cars. The best petrol/electric cars (the vast majority of this type) manage less than 80mpg on average (see Top ten most fuel efficient hybrids), while the best of the conventional cars are nearer 90mpg (see Best mpg cars 2015). Making a direct comparison is in any case difficult, because the hybrid figures take no account of generating electricity. Nevertheless, these are the figures which the motorist will be aware of.
This is not the whole story, of course. Hybrid vehicles have advantages in urban driving, when the batteries come into their own. Electric motors can improve fuel economy and reduce emissions of nitrous oxide and particulates, which are a problem for air quality in cities. But whether or not this is a real plus depends on whether the car is driven mostly in cities. If a large proportion of the mileage is long distance, the advantage disappears and even becomes a handicap as more fuel is needed to move the heavier car.
But there is no denying that hybrid vehicles represent a clever and practical use of technology, giving cars which are a direct replacement for conventional ones. Not so for electric cars, which are unlikely to be useable for longer distance driving for some time to come. Even in cities, the need for extended ‘refuelling’ (charging) periods reduces their flexibility.
Coming back to running costs, the report suggests that, by 2030, the current average spending on fuel – £1,190 – could be cut by about £960 for fully electric vehicles and £600 for the average new low-carbon car. What it doesn’t say is that the ‘average’ low carbon car would be a mix of conventional and hybrid vehicles, with a lot of the purported savings coming from further clever engineering of existing engines. For general motoring, it is doubtful that hybrids, however clever, would offer the average motorist sufficient added value to justify a significant premium.
For electric cars, the situation would be even more pronounced. Despite the optimism and enthusiasm from Cambridge Econometrics, it seems more likely that electric and hybrid cars will be attractive mainly in cities, with the projected overall penetration figures continuing to look over-optimistic. Unless, that is, there are technical breakthroughs, in which case the market will decide.
If I’m wrong and plug-in vehicles become a major part of the market, there will have to have been substantial investment in charging networks to avoid a significant number of people being stranded. It is difficult to believe that the purported saving in fuel costs would be realised for long. The government of the day will be very keen to replace the loss of fuel duty implied by the switch away from petrol and diesel.
Martin Livermore
The Scientific Alliance
St John’s Innovation Centre
Cowley Road
Cambridge CB4 0WS
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