London leads charge towards sustainable megacities

London is the only 'megacity' in the world where electricity use per capita is going down while GDP is going up, according to a new University of Toronto study.

The UK capital’s success can be attributed to rising electricity prices, according to the report, as a result of the country’s decarbonisation policies. The city also has effective taxes on waste disposal and a comprehensive public transport system.

London was recently ranked as the world’s second most sustainable city by the Arcadis Sustainable Cities Index. That ranking was reinforced by this new  study, which examined the ‘metabolism of megacities’ – i.e. the amount of resources consumed and waste produced by urban areas larger than 10m people.

But London was the exception rather than the rule, as the world’s megacities are home to 6.7% of the world’s population, yet they consume 9.3% of global electricity and produce 12.6% of global waste.

Losing efficiency

As these huge cities spread into the suburbs, they tend to lose the energy and transport efficiencies usually associated with urban dwelling. According to lead researcher Chris Kennedy, some cities are guiltier than others.

“The New York metropolis has 12 million fewer people than Tokyo, yet it uses more energy in total: the equivalent of one oil supertanker every 1.5 days,” he said. “When I saw that, I thought it was just incredible.”

Tokyo’s efficient design and vast network of public transit reduces its environmental impact, and demonstrates that in some cases, smart urban policies can reduce resource use, even in the face of rising GDP and exploding populations.

Tokyo has also aggressively addressed leaky pipes, a strategy that has reduced water losses to 3%. This compares to over 50% in cities like Rio de Janiero and Sao Paolo.

“These are places that are really short of water, and yet they’re leaking it away,” said Kennedy.

Kennedy, also a senior fellow at the Global Cities Institute, explained that some of the differences have to do with geography: colder megacities like Moscow and New York use more fuel for heating, while economic activity also makes a difference.

“Wealthy people consume more stuff and ultimately discard more stuff,” he said. The average New Yorker uses 24 times as much energy as a citizen of Kolkata, and produces more than 15 times as much solid waste.

Reasons for optimism

Kennedy was quick to point out that examples like London, Tokyo and Moscow – which has built the largest district heating system in the world – can lead the way for a more sustainable future.

“What we’re talking about are not short-term, one-election issues, but long-term policies on infrastructure that shape cities over years or decades,” said Kennedy.

“The evidence is that megacities can make some progress in reducing overall resource use, and I think that’s encouraging.”

Brad Allen

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