Does Energy Efficiency Reduce Emissions and Peak Demand? A Case Study of 50 Years of Space Heating in Melbourne

This paper examines the relationship between space heating energy efficiency and two related but distinct measures; greenhouse mitigation, and peak demand. The historic role of Melbourne's space heating provides an opportunity to assess whether improvements in energy efficiency lead to sustained reductions in energy consumption or whether rebound factors take back efficiency gains in the long run. Despite significant and sustained improvements in appliance efficiency, and the thermal efficiency of new building fabrics, the per-capita heating energy consumption has remained remarkably stable over the past 50 years. Space heating efficiency is bound up with notions of comfort, sufficiency and lifestyle, and the short-run gains from efficiency become incorporated into a new set of norms. It is this evolution of cultural norms that reconciles the contradiction between the short-run gains from efficiency measures, with the efficiency rebound that becomes evident over the long-term. The related, but distinct peak demand measure can be influenced by efficiency measures, but energy efficiency measures will not alter the requirement for large-scale conventional energy to provide affordable and reliable winter heating.