by John R. Nolon
Sydney GHG 2030 Business as Usual Projections. Note the concentration of high emission levels in the downtown area and the magnitude of the emissions, as emphasized by the inset.
In “Get Out of Town,” The New Yorker‘s Nicholas Lemann raises two critical questions: has the celebration of cities gone too far and is city life productive or merely interesting? Some facts are missing from his June 27, 2011, “A Critic at Large” column.
Sydney's 2030 GHG Emissions with Trigeneration. Note the reduction in emissions, especially in the most intense areas of emission.
Americans, on average, emit over twenty-five metric tons of carbon dioxide owing to their automobile travel and 2,500 square foot homes; buildings consume the lion’s share of the nation’s electricity much of which is produced by coal-fired generation plants. Over three quarters of electricity is wasted in transmission from far-removed generation sites to populations living and working in spread-out metropolitan areas. All of these human settlement factors contribute heavily to the steady uptick of carbon dioxide in the atmosphere, creating the greenhouse effect that is warming the planet, causing sea level rise, increasing the ferocity of storms, and threatening the settlements in which we live. With such an impact on the global climate system, management of human settlement patterns is a means of significantly mitigating greenhouse gas emissions.
City dwellers, on average, produce half the carbon emissions of their suburban counterparts due in large part to available transit, mixed-use neighborhoods, and energy efficiency of the neighborhoods and buildings they inhabit. Sydney, Australia, estimates that it can displace “approximately 500 MWe of coal-fired electrical capacity” by supplying integrated heating and cooling infrastructure that takes advantage of the possible efficiencies provided by urban density and mixed land uses. The proposed trigeneration plan would reduce the electric grid supplied energy within the Low Carbon Infrastructure Zones from 2,850 GWhe to 550 GWhe by 2030. This plan would thus reduce the greenhouse gas emissions related to these zones from 2.9 MT CO2-e to 1.8 MT CO2-e.
As the consequences of climate change become more evident, there should be no doubt that cities are more than interesting. Celebrating cities may be a survival technique, particularly as we consider where to put the 100 million additional Americans the Census Bureau projects we will have by 2040.