Seminar: Considering a Population, Urbanization/Density, Energy/Emissions Nexus (18 Mar 16)

Friday 18 March 2016, 1-2pm, Seminar Room 8.119 (a/b), School of Earth and Environment

Speaker: Brantley Liddle, Centre for Strategic Economic Studies, Victoria University

This presentation ties together research on (i) demography and environmental impact, (ii) urban density and transport energy consumption and emissions, and (iii) the usefulness of national-level urbanization for explaining environmental impact. While larger families use more energy than smaller ones, they use less energy per person; hence, average household size has a negative relationship with road energy use and carbon emissions. Studies that have considered age structure typically have used standard World Bank definitions, and mostly have found those variables to be insignificant. However, when researchers have considered levels of disaggregation that approximate life-cycle behavior (like family size), they have uncovered relationships that are complex and nonlinear. For example, considering transport, young adults were energy intensive, whereas the other cohorts had negative coefficients. For residential electricity consumption, age structure had a U-shaped impact. Urban density is negatively correlated with urban private transport energy consumption. Per capita urban transport-related emissions of CO and NOx increase and then decline at observed income levels—a result driven by a similar inverted-U relationship between income and emissions technology (i.e., emissions per passenger-km). However, for urban transport energy consumed, the estimated turning point was well beyond the sample bounds. Passenger-km per capita and car ownership both rise, and public transport’s share of those passenger-km falls monotonically with income. Lastly, urbanization appears positively associated with energy consumption and carbon emissions—although the causal direction is ambiguous.

Brantley Liddle received an interdisciplinary Ph.D. from the Massachusetts Institute of Technology’s Sloan School of Management and Department of Civil and Environmental Engineering. His research falls in the broad field of population-environment-development interactions. He is now a senior research fellow at the Centre for Strategic Economic Studies at Victoria University in Melbourne, Australia, where he leads the Centre’s energy/environment economics modeling research program. Among his areas of research interest/expertise are population change and the macro environment; energy and the macro economy; and transport and energy consumption.

This seminar is jointly hosted by the School of Geography, the Sustainability Research Institute and the Institute for Transport Studies.

Open to University of Leeds staff and students.