Over half of the population of the world live in
urban areas. This means that efforts to meet human
development goals and sustain economic growth
must be concentrated in cities. However, the pursuit
of more prosperous, inclusive and sustainable urban
development is complicated by climate change, which
multiplies existing environmental risks, undermines the
effectiveness of existing infrastructure, and creates new
resource constraints.
In this paper, we conclusively demonstrate that there

Many recent major studies, including the IPCC’s Fourth Assessment Report, have attested that energy efficiency is humanity’s prime option to combat climate change in the short- to mid-term. The potential to avoid CO2 emissions cost-effectively has been reported to be significant through efficiency policies. However, the review of global research findings on the quantification of cost-effectiveness of opportunities through improved efficiency has highlighted that there is a major shortcoming in the vast majority of such calculations.

Cities are crucial sites for achieving socio-technical transitions in technology and infrastructure systems. Raising building energy efficiency (BEE) through new construction or retrofitting holds particular relevance to sustainability transitions since this requires diffusion of new technologies and energy management practices. In pursuit of this, city policymakers around the world are increasingly utilising mixes of multiple policy instruments.