Dense, transit-oriented development is more environmentally friendly than suburban sprawl. But city dwellers shouldn’t get too smug about that. Just because an urban apartment uses fewer resources than a McMansion doesn’t always mean that its inhabitants use fewer resources than suburbanites.
This is the upshot of a remarkable 2007 analysis of consumption in Australia that I recently learned about. My source of enlightenment was a not-very-convincing opinion piece by prominent anti-urbanists Joel Kotkin and Wendell Cox. Defending single-family zoning, they write:
“In fact, suburban houses, according to data in one Australian study [conducted by co-author Cox’s consultancy], use less energy than do the dwellings of inner-city urbanites.”
This claim is diametrically opposed to the received wisdom of the past couple of decades. It is also, I learned soon after clicking through to Cox’s “study,” false. What Cox’s consultancy produced was really just an interpretation of the Australian Consumption Atlas compiled by the Australian Conservation Foundation and the Centre for Integrated Sustainability Analysis at the University of Sydney, which did not find that suburban houses use less energy than the dwellings of inner-city urbanites.
Families are more resource-efficient than single-person households.
It did find, however, that residents of the outer suburbs of Australian cities used less energy per capita than those who lived closer to downtown, which is pretty interesting.
The Consumption Atlas was, as the name indicates, an attempt to map the environmental impact of consumption by households all over Australia. Only 20% of greenhouse-gas emissions, 23% of water use, and 7% of the overall “eco-footprint” of households were attributed to direct household uses such as heating, lighting and watering the garden. The rest – the vast majority – came from the things that people who lived in those dwellings bought and did. More-affluent people can afford to buy and do more things, and in Australia, more-affluent people tend to live closer to downtown.
In the U.S., the wealthiest areas in the U.S. are still generally suburban.
It’s doubtful that mapping overall environmental impacts in the U.S. would deliver such a smooth urban-to-suburban continuum as in Australia. But existing U.S. research that tracks direct energy use for heating, electricity and local transportation – and finds cities to be much greener per-capita than suburbs – definitely misses out on some of the ways that affluent urbanites can have big environmental footprints. The most obvious is air travel.
In his analysis of the Consumption Atlas data, Cox acknowledged that incomes and environmental impact were closely linked, but noted that some suburban areas had lower per-capita environmental impact than closer-in neighborhoods with similar household incomes.
The main reason was that suburban homes tend to house more people. When a resource such as energy or furniture is shared by more people, the per-capita environmental burden drops. Families are more resource-efficient than single-person households. And in general, one- and two-person households are more common in dense, urban neighborhoods than in sprawling suburbs.
The Consumption Atlas evidence clearly complicates the increasingly standard narrative of cities as environmental saviors. As U.S. cities become more affluent, their environmental footprint may grow, and if people who want to have children feel compelled to move to the suburbs, that’s not exactly to the credit of cities.
Getting food into the city from farms, and other goods from warehouses, surely takes longer [and consumes more energy] there too. Big cities are great, but they’re not the solution to all the world’s environmental challenges.
Justin Fox is a Bloomberg Opinion columnist.