By 2020, there will be 37 megacities across the world. These areas will account for 14.6 per cent of global GDP, but will also consume a disproportionate share of the world’s resources.
Megacities are currently home to 6.7 per cent of the global population, and consume 9.3 per cent of electricity while producing 12.6 per cent of global waste, according to new research led by the University of Toronto.
But some megacities are better than others when it comes to resource consumption. ‘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,’ says Chris Kennedy from the University of Toronto.
Temperature plays a role in the differences between urban areas. The colder megacities use more fuel for heating. Moscow and New York are leaders in energy consumption for heating. Moscow has the largest district heating system in the world, which combines heat and power to buildings housing over 12 million people.
Economics is also a factor. ‘Wealthy people consume more stuff and ultimately discard more stuff,’ says Kennedy. A New Yorker uses 24 times more energy than a Kolkatan, and produces 15 times more solid waste.
The average New Yorker uses 24 times as much energy as a citizen of Kolkata, and produces over 15 times as much solid waste. Efficiency also plays a role, Tokyo has reduced water loss to three per cent through targeting leaky pipes and Seoul reclaims wastewater for secondary uses, such as flushing toilets. This contrasts with Rio de Janiero and Sao Paolo where a consistent 50 per cent leakage contributes to an ongoing water crisis in Brazil.
As for the UK’s only megacity, London was the only place on the list that saw per capita electricity use decline as GDP increased.