2008/06/01

GHG Emissions Less in Auto Oriented Suburbs than Urban Cores: Australia

Deflating the Myths on Greenhouse Gas Emissions

Policy Conclusions: This report summarizes the data developed by the Australian Conservation Foundation in its Conservation Atlas. This nearly 100-page report provides detailed information by local authority area (geographical sector) of Australia’s largest urban areas. The conclusions are different than would have been anticipated.

Lower GHG emissions are associated with urban fringe locations, not the core.

Lower GHG emissions are associated with higher rates of detached housing.

Lower GHG emissions are associated with greater automobile use.

Lower GHG emissions are associated with lower population density.


Repealing the “Great Australian Dream”? Climate change concerns have propelled the issue of reducing greenhouse gas emissions to the top of the public policy agenda. For some years the urban planning community and other interests have sought to contain urban expansion (pejoratively called “urban sprawl”) and force more dense development through policies referred to as “smart growth” or “urban consolidation.” There is a presumed preference for multi-unit residential development in city cores and an aversion against low-priced detached housing on the urban fringe. An important objective of these policies has been to reduce automobile use, which it is assumed will naturally occur as a result of higher urban densities,

In Australia, these policies have seriously limited the availability of market priced land on the urban fringe and driven house prices up at a far greater rate than has occurred in international urban areas where compact city policies have not been implemented. Thus, the present dominant policies are at odds with the “Great Australian Dream,” which has been based upon detached housing on the fringe and automobile access.

Smart Growth and GHG Emissions: The urban consolidation agenda is perceived by many to be an appropriate strategy for reducing GHG emissions. Part of this is due to the fact that automobiles are an obvious example of fossil fuel use.

Generally, urban planning policy assumes that greenhouse gas emissions are higher in portions of urban areas that are more suburban, especially areas in which there is a preponderance of single-family detached housing. There is also the assumption that greenhouse gas emissions are lower in higher density areas, especially where there are more high-rise condominium and apartment buildings. And, as noted above, a parallel perception is that greenhouse gas emissions are greater in portions of the urban area that rely more on cars, and less where there is greater dependence on public transport. Finally, higher population densities are associated with lower GHG emissions.

The Reality: However, reducing GHG emissions is not so simple as to be achieved through the urban consolidation agenda. Indeed, there is considerable evidence to the contrary.

GHG emission estimates from the recently published Australian Conservation Foundation Consumption Atlas, indicates virtually the opposite of the generally held perceptions. The data shows that lower density areas, which rely more on automobiles, tend to produce less in GHG emissions than the high density, more public transport dependent areas that are favored by urban consolidation policies.

The reality, as indicated by data from the Australian Conservation Foundation’s Consumption Atlas is virtually the opposite.

The Consumption Atlas: The Consumption Atlas relies on a holistic approach, which allocates greenhouse gas emissions to final consumption at the household level. This includes not only direct energy consumption (such as household electricity use and automobile use) but also a much larger component, indirect energy consumption, which includes GHG emissions from electricity generation, manufacturing, processing, transport and otherwise producing consumer products. The Consumption Atlas provides a groundbreaking model for GHG emission analysis that establishes a model for the field, not only for Australia but also around the world.

The approach of the Consumption Atlas avoids what could deteriorate into agenda-driven approaches that focus only on the particular GHG producing sectors that are in the political sites of interest groups. Any approach that begins at any level other than allocating all GHG emissions to specific final consumption runs this risk. For example, the authors note that emphasis on direct consumption (such as automobile use and land use policy) may be “misdirected since direct energy use constitutes remarkably small portion of the total energy requirement over a range of incomes.”

The more important risk is that agenda-driven policies may fail to achieve the objective of substantially reducing GHG emissions. Any serious, good faith program for reducing emissions must be based upon comprehensive analysis that does not begin with pre-conceived notions, despite their popularity even at the highest policy levels.

Note: This report was prepared by Demographia for the Residential Development Council of the Property Council of Australia.