Heating and cooling energy trends and drivers in buildings
The purpose of this paper is to provide a source of information on thermal energy use in buildings, its drivers, and their past, present and future trends on a global and regional basis. Energy use in buildings forms a large part of global and regional energy demand. The importance of heating and cooling in total building energy use is very diverse with this share varying between 18% and 73%. Biomass is still far the dominant fuel when a global picture is considered; the role of electricity is substantially growing, and the direct use of coal is disappearing from this sector, largely replaced by electricity and natural gas in the most developed regions. This paper identifies the different drivers of heating and cooling energy demand, and decomposes this energy demand into key drivers based on a Kaya identity approach: number of households, persons per household, floor space per capita and specific energy consumption for residential heating and cooling; and GDP, floor space per GDP, and specific energy consumption for commercial buildings. This paper also reviews the trends in the development of these drivers for the present, future - and for which data were available, for the past - in 11 world regions as well as globally. Results show that in a business-as-usual scenario, total residential heating and cooling energy use is expected to more or less stagnate, or slightly decrease, in the developed parts of the world. In contrast, commercial heating and cooling energy use will grow in each world region. Finally, the results show that per capita total final residential building energy use has been stagnating in the vast majority of world regions for the past three decades, despite the very significant increases in energy service levels in each of these regions.
Energy use in buildings in a long-term perspective
Energy services in and related to buildings are responsible for approximately one-third of total global final energy demand and energy-related greenhouse gas emissions. They also contribute to the other key energy-related global sustainability challenges including lack of access to modern energy services, climate change, indoor and outdoor air pollution, related and additional health risks and energy dependence. The aim of this paper is to summarize the main sustainability challenges related to building thermal energy use and to identify the key strategies for how to address these challenges. The paper's basic premises and results are provided by and updated from the analysis conducted for the Global Energy Assessment: identification of strategies and key solutions; scenario assessment; and the comparison of the results with other models in the literature. The research has demonstrated that buildings can play a key role in solving sustainability challenges: close to one-third of 2005 building energy use can be eliminated by the proliferation of state-of-the-art construction and retrofit know-how in each world region, while maintaining wealth and amenity increases. In contrast, approximately 80% of this 2005 energy use will be locked in by the middle of the century if policies are not sufficiently ambitious in targeting regionally specific state-of-the-art performance levels. © 2013 Elsevier B.V.