Urban density significantly impacts urban energy use and the quality of life of urban residents. Here, the authors provide a global-scale analysis of future urban densities and associated energy use in the built environment under different urbanization scenarios. The relative importance of urban density and energy-efficient technologies varies geographically. In developing regions, urban density tends to be the more critical factor in building energy use. Large-scale retrofitting of building stock later rather than sooner results in more energy savings by the middle of the century. Reducing building energy use, improving the local environment, and mitigating climate change can be achieved through systemic efforts that take potential co-benefits and trade-offs of both higher urban density and building energy efficiency into account.
Using both top-down and bottom-up approaches and scenarios, the authors examine building energy use for heating and cooling. Globally, the energy use for heating and cooling by the middle of the century will be between 45 and 59 exajoules per year (corresponding to an increase of 7–40% since 2010). Most of this variability is due to the uncertainty in future urban densities of rapidly growing cities in Asia and particularly China. Dense urban development leads to less urban energy use overall. Waiting to retrofit the existing built environment until markets are ready in about 5 years to widely deploy the most advanced renovation technologies leads to more savings in building energy use. Potential for savings in energy use is greatest in China when coupled with efficiency gains. Advanced efficiency makes the least difference compared with the business-as-usual scenario in South Asia and Sub-Saharan Africa but significantly contributes to energy savings in North America and Europe. Systemic efforts that focus on both urban form, of which urban density is an indicator, and energy-efficient technologies, but that also account for potential co-benefits and trade-offs with human well-being can contribute to both local and global sustainability. Particularly in growing cities in the developing world, such efforts can improve the well-being of billions of urban residents and contribute to mitigating climate change by reducing energy use in urban areas.
In response to feedback, high-income households can reduce their energy use to a larger degree than low-income households (17% vs 3% reduction). This and other insights were gained by two rapid reviews into research, both Australian and International, on digital services and...Read more
Many established homes (most Australian homes) perform quite poorly in terms of energy efficiency and other resource use. Home renovation is a key point at which sustainability could be improved as people have already decided to spend money on renovation (some $32b a year...Read more
Financing the upfront costs of energy efficiency and renewable energy projects in buildings can be a significant barrier to the expansion of sustainable, low carbon buildings, despite this being a low-cost option on the carbon abatement curve. Systematic literature on...Read more
This paper explores potential future implications of climate change on building energy expenditures around the globe. Increasing expenditures result from increased electricity use for cooling, and are offset to varying degrees, depending on the region, by decreased energy consumption for heating. The analysis is conducted using a model of the global buildings sector within the GCAM integrated assessment model.
India is expected to add 40 billion m2 of new buildings till 2050. Buildings are responsible for one third of India's total energy consumption today and building energy use is expected to continue growing driven by rapid income and population growth. The implementation of the Energy Conservation Building Code (ECBC) is one of the measures to improve building energy efficiency.
There is ample evidence of the cooling effects of green infrastructure (GI) that has been extensively documented in the literature. However, the study of the thermal profiles of different GI typologies requires the classification of urban sites for a meaningful comparison of results, since specific spatial and physical characteristics produce distinct microclimates.