The trend towards larger, heavier car sales is probably the best demonstration that we are not taking the climate emergency seriously.
New cars now weigh 1.5 tonnes, growing a staggering 300kg in the past two decades. Each car is carrying around extra weight equivalent to four adults.
This “autobesity” had many downsides.
Carrying this extra weight pushes up the fuel consumption of a typical car substantially. Over the course of its whole life, driving maybe 300,000km, this amounts to an extra 1,500 litres of petrol and diesel, which, when burned, emits 3.5 tonnes of carbon dioxide and more air pollution, from the exhaust and from the tyres and road. It also makes driving more expensive and exacerbates the energy insecurity from which Ireland suffers because of fossil fuel dependence.
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Larger cars also take up more space, increasing the threat to other road users. The streets of Irish towns and cities are already vehicle-centred, rather than human-centred. The bloat of cars reinforces their dominance on the roads. It is not surprising that people prefer to be inside a car than to be on the street, walking or cycling. Increasing car dependency and more hostile streets then, of course, perpetuates more car use: in 1986, nearly three times more children and students propelled themselves to school and college on foot and bike than by car. Now, the situation is reversed, and twice as many are driven.
While the weight of individual car models is growing, the new car market is also shifting towards larger vehicle segments. The popularity of SUVs has boomed. They now account for 60 per cent of new car sales, five times greater than just 10 years ago. Their distinctive shape, with a higher bonnet and driving position, is more comfortable for the occupants of the car and gives a sense of security to the driver, but makes the streets less safe for others. One study showed that children are eight times more likely to die when hit by an SUV, compared to a regular car.
Even with the enactment of the far-reaching targets outlined in the climate action plan, the transport sector is set to significantly overshoot its allocated share of the carbon budgets
While some people need larger cars for work or to carry around a large family, those factors are not driving the trend. Carmakers are heavily promoting larger cars because they are more profitable.
Prof Kevin Anderson told a meeting of the Oireachtas Joint Committee on Climate Action that “if there is a climate emergency, you do not sell SUVs”. It is hard to disagree. According to the International Energy Agency, the growing trend towards larger cars is a major factor behind growing greenhouse gas emissions: the oil consumption of SUVs globally increased by 500 000 barrels per day last year, accounting for one-third of the total growth in oil demand.
Even with the enactment of the far-reaching targets outlined in the climate action plan, the transport sector is set to significantly overshoot its allocated share of the carbon budgets, which constrain Ireland’s total greenhouse gas emissions between 2021 and 2030. Making up for this after 2030 will become increasingly infeasible. To meet the legislated carbon budgets, the Government must find new ways of cutting emissions, and accelerate the measures already in place.
One measure to help bend the emissions curve downwards is to incentivise lighter, smaller cars through the taxation system.
Several countries, including Norway, France and Sweden, tackle car bloat by adding vehicle weight as a component of the vehicle registration tax. A tax at the point of sale, rather than during ownership or car use, is more fair to people who rely on the second-hand car market to buy cars.
Some European cities are also charging larger cars more for parking, which is a rational response to the encroachment of bulky vehicles.
Advertising and marketing are powerful forces encouraging people towards larger cars, which could be counteracted through public safety and climate messaging
Electric vehicles are also growing in weight and size, and the current taxation system does not promote efficiency and smaller sizes in this market. While electric cars emit far lower greenhouse gases, this increasing weight has the same downsides for public safety and also drives more electricity demand.
Taxation is not the only policy measure available. Advertising and marketing are powerful forces encouraging people towards larger cars, which could be counteracted through public safety and climate messaging. In France, a law has been passed that requires car adverts to encourage alternatives to driving, like walking and cycling. When a car is sold, its weight, size and lifetime fuel cost and carbon dioxide pollution could be made prominent, including information about the downsides of larger cars.
Or we could simply take the same approach we have to cigarettes, and ban car advertising completely.
There is a real danger that this topic will become inflamed into a divisive, culture-war issue. The Government can learn from how it very successfully approached the smoking ban nearly 20 years ago; this is not about shaming or demonising car drivers but about fulfilling the values that the vast majority of us share — protecting vulnerable people, and the planet.
- Hannah Daly is professor of sustainable energy at University College Cork