Cities will not be able to achieve significant reductions in greenhouse gas emissions without addressing peoples’ attachment to cars. The most effective way to do this is road pricing.

Transport accounts for 97% of the increase in global demand for oil, which is set to rise from 84.7m barrels per day (bpd) in 2008 to 105m bpd in 2030. The global number of road vehicles is estimated to nearly double from just over one billion in 2010 to two billion in 2020. For example, there are now six million vehicles on the roads in the National Capital Territory of Delhi, a number which is increasing at the rate of 1,000 per day.

Reducing this demand for fossil fuel-derived energy is difficult because many people have developed a strong attachment to one of the most carbon-intensive forms of transit – the petrol/diesel car.

While new technologies offer the prospect of low carbon personal transport in the future, most cities will exceed their carbon targets if they can’t achieve a significant modal shift from cars to public transport, walking and cycling. There are also wider societal benefits to doing this, such as greater public space and improved health.

At present, most cities are going in the opposite direction. One of the exceptions is London, where the combination of a ground-breaking road pricing scheme – the central London congestion charge – and significant investment in alternatives to the car, has achieved a 5% modal shift in the right direction. Significantly for the long term, this includes a massive 120% increase in cycling, albeit from a low base compared to some other European cities.

It is difficult to see how other well-established cities around the world can avoid adopting similar policies before too long. The lesson from London, Stockholm and Milan – which have succeeded in introducing road pricing (unlike New York and Manchester which have tried and failed) – is that it is possible to introduce charges for driving as long as there are clear alternatives, and the electorate doesn’t have to vote on the proposition until after they have seen that it works.

Is that the price we have to pay to achieve carbon reduction?

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