1 TRANSPORT AND ENERGY CONSUMPTION: DOES CO-LOCATION OF HOUSING AND WORKPLACES OCCUR OVER TIME?

Transport and energy consumption is an increasingly important topic in the light of global warming, sustainability and (even) energy security issues. The role of urban planning in helping to reduce transport energy consumption continues to be underplayed in research, policy and practice. Current urban planning practice, particularly in suburban areas, tends to increase traffic volumes by dispersing activities and hence facilitates private car travel rather than that by public transport, walking or cycling. This paper examines the impact of time on the urban form and travel relationship and assesses whether housing and workplaces naturally “co-locate ” over time, testing the proposition that workplaces are following residences to the suburbs, hence travel distance reduces over time. But even if distance is reduced, the use of the car increases and aggregate energy consumption increases. Although aggregate distance co-location might occur, focusing on the aggregate trend also hides several kurtosis effects: households located at higher densities, closer to major strategic centres, in areas with good public transport accessibility and strong jobs-housing balance all have the potential to reduce their commuting travel distance. Urban planning therefore remains as a critical tool in efforts to reduce energy consumption in the transport sector. A “smart growth ” strategy is most likely to help enable a reduction in transport energy reduction, but the success of this requires more than a simple focus on density.