Common Urban Myths About Transport
Myth: Cars are becoming more fuel efficient
Fact: While it’s true that engines get steadily better at using fuel, people have responded by buying more fuel-hungry cars. As a result, the average efficiency of the Australian vehicle fleet has not changed significantly since figures were first collected in 1963.
Hopes that car use will become more sustainable through better fuel economy are widespread, and often exploited for political advantage. In 2007, for example, then State Treasurer John Brumby used this myth to defend cuts to stamp duty on large new cars:
Such hopes have been likened to walking down an ‘up’ escalator. Even if vehicles become on the whole more fuel efficient, motorists can be expected to respond much as they would to a drop in petrol prices: by driving further and more often.
However, there is little indication that the cars we actually drive are becoming any more fuel efficient. In Britain, the Royal Commission on Environmental Pollution found that, while the fuel economy of new British cars improved during the oil shock of the late 1970s and early 1980s, fuel economy has actually worsened since then.
Australian figures for fuel economy tell a similar story. For some decades, the Australian Bureau of Statistics has conducted a Survey of Motor Vehicle Usage, which estimates the average fuel consumption of all Australian passenger vehicles on the road. This figure has hovered slightly above or below 12 litres per 100 km over the entire period for which data have been collected. The most recent available figure (from 2010) of 11.3 litres/100km is the same as for 2002, and barely any lower than the very first figure collected in 1963, nearly half a century earlier!
The same ABS data tells us that in 2006, those driving cars purchased since 2000 got an average fuel efficiency of 12.1 litres per 100km, one litre higher than the average efficiency of cars purchased between 1990 and 1999, of 11.1 litres per 100km. So despite what John Brumby might say, it is clear that newer doesn’t always mean more economical.
It is likely, as transport researcher Patrick Moriarty argues, that improvements in engine efficiency over the decades have been offset by other factors: the trend toward larger vehicles such as four-wheel-drives, increased use of air conditioning, electronic control components demanding greater weight and power input, ageing of the car fleet, and compromises required to reduce air pollution.
Compounding this is the psychology of car buyers themselves. American author Tom McCarthy in Auto Mania, his 2007 history of the US car market, argues that the oil shocks of the 1970s, far from driving a trend toward greater fuel economy, actually undermined the desire for efficiency among consumers in the longer term. This is because during these oil shocks, fuel economy became associated in people’s minds with material deprivation, denial and sacrifice. Once oil prices came down in the 1980s, people could barely wait to take advantage of this with bigger and more fuel-hungry cars, through a simple urge to demonstrate their new-found control over circumstances. In Australia, we can liken this to an earlier event: Robert Menzies’ abolition of postwar petrol rationing in 1949 similarly unleashed a tide of latent demand for car travel, and the ceremonial burning of ration books that represented forced economies.
In recent years, hybrid petrol-electric vehicles have hit the market amid a flurry of marketing hype that promises astounding fuel efficiencies, with ads promising that you’ll only have to visit a petrol station once a year or less. But as early as 2005, hybrids in America were starting to follow the same old trend: improvements in engine efficiency were being used not to reduce fuel consumption, but to put more ‘grunt’ under the bonnet.
Sure enough, recent industry reports show the Australian hybrid car market falling in with the American pattern:
Hybrid or not, with each passing decade our cars have increased steadily in weight and engine power in line with improvements in engine technology. After all, what new car buyer can resist a bigger and more powerful car that costs the same to run as their previous vehicle?
This is also why glowing reports of new hi-tech ‘ultra-efficient’ cars like this one are of little relevance to the urban transport problem (at least until petrol is much more expensive than it is now). Quite simply, the factors that make these vehicles highly efficient also make them less attractive to the typical motorist. The world record for vehicle fuel efficiency has already been set for all time by the bicycle, which has infinite efficiency since it requires no fuel at all. A motorist who wishes to maximise their fuel efficiency would be well advised to just switch to cycling. On the other hand, a motorist who finds riding a bike unattractive is unlikely to be attracted to these ultra-efficient vehicles for much the same reasons.
In Victoria, the idea that people will suddenly buck all historical trends and embrace vastly more efficient cars, thereby slashing transport emissions, achieved new prominence in 2008 with the release of two reports by management consultants the Nous Group. These reports put forward scenarios for achieving big cuts in Victoria’s greenhouse emissions, and in transport, the biggest cut was said to be achievable though improved fuel efficiency. One of these reports was produced for Environment Victoria, and has apparently strengthened the belief among some environmentalists that it is more important to pursue improvements in car technology than to seek better public transport.
To obtain their conclusion, the Nous consultants blithely assumed a wildly optimistic reduction in fuel consumption of 30% between 2010 and 2022, increasing to a 60% reduction by 2030. Not only is such a reduction utterly without precedent, including in the oil shocks of the 1970s: according to analysis by the Bus Association of Victoria, it would require every new car purchased from 2010 onwards to be as efficient as a Toyota Prius!
Policymakers and their consultants such as Nous are seduced by the idea that cars only use as much fuel as they do because of insufficient take-up of new technology, and there is a huge ‘free lunch’ to be had simply from decreeing tough new efficiency standards. Vehicle efficiency improvements in Europe are commonly held up as an example, but this ignores the fact that the trend toward smaller vehicles there predates the development of aggressive standards (having arguably helped make those standards politically palatable), and owes as much to Europe's high fuel prices, greater respect and provision for public and non-motorised transport, and closer settlement patterns as any other factor.
In addition, at least some of those efficiency gains in Europe may be illusory. According to a 2012 report to the European Commission, about a third of the ‘registered’ CO2 emission reductions from new cars between 2002 and 2010 have not actually occurred. It appears instead that flawed test procedures and ‘flexibilities’ in these procedures have been exploited by carmakers to produce ‘laboratory’ fuel efficiency figures about 30% more optimistic than drivers will achieve in reality.
As we emphasise in our discussion of car pooling, emissions reduction forecasts and other such figures are little better than random numbers unless they compare achievable outcomes in one area with what is achievable in another area with the same effort. Big gains in public transport patronage have been shown to be achievable: similar big gains in the efficiency of the national car fleet have not, either in the past or today. ‘Green motoring’, to the Federal Government in 2009, simply meant reducing the Commodore’s fuel use from 10.6 to 9.3 litres per 100km. A 2013 report from the US National Academy of Sciences likewise suggests that technology alone will not suffice to cut energy use and emissions by the amount required in a low-carbon future.
When it comes to the environmental impact of each ‘unit’ of car use, in particular greenhouse emissions, things have not actually stayed the same but have actually got slightly worse over time. This is because the catalytic converters found in today’s cars, while reducing some emissions from unburnt fuel in the exhaust, also increase emissions of some chemicals like nitrous oxide (N2O) which act as local pollutants and also happen to be potent greenhouse gases. Thus, the average greenhouse emissions from each kilometre travelled in a car increased by about 5 per cent between 1991 and 2002 (the period when most cars on the road acquired modern three-way catalytic converters) or by 8 per cent for car travel in urban areas.
Source: Australian Greenhouse Office. National Greenhouse Gas Inventory: Analysis of Recent Trends and Greenhouse Indicators 1990 to 2002.
As the National Greenhouse Inventory also reminds us, the total passenger-kilometres travelled in cars increased by 18 per cent, and vehicle-kilometres by 25 per cent, over that same period (1991 to 2002). Vehicle-kilometres have grown faster, because each car now carries fewer passengers on average than in 1991.
As Paul Mees concludes:
Or, as a Canadian journalist summed it up:
© 2010 Public Transport Users Association Inc. (PTUA), Victoria, Australia. ABN 83 801 487 611.
Last modified: 21 March 2013