The building sector — which accounts for 30% - 40% of global energy use — can substantially reduce carbon dioxide emissions world-wide through appropriate government regulations, greater use of energy-saving technologies and behavioral changes, concludes a new report by the United Nations Environment Program Sustainable Building and Construction Initiative (SBCI).
The report cites numerous existing opportunities for governments, industry and consumers to take actions during the life span of buildings that will help mitigate the effects of global warming.
"Energy efficiency, along with cleaner and renewable forms of energy generation, is one of the pillars upon which a de-carbonized world will stand or fall," said Achim Steiner, U.N. under-secretary general and executive director of the U.N. Environment Program.
"The savings that can be made right now are potentially huge and the costs to implement them relatively low if sufficient numbers of governments, industries, businesses and consumers act," he added.
By some conservative estimates, the building sector world-wide could deliver emission reductions of 1.8 billion tons of CO2, Steiner added. "A more aggressive energy efficiency policy might deliver over two billion tons, or close to three times the amount scheduled to be reduced under the Kyoto Protocol," Steiner explained.
Other key points of the report include:
Typically more than 80% of total energy consumption takes place during the use of buildings — for heating, cooling, ventilation, lighting, etc. — and less than 20% during their construction. Therefore, the report pushes for a greater use of existing technologies such as thermal insulation, solar shading and more efficient lighting and electrical appliances, as well as the importance of educational and awareness campaigns.
Advanced, expensive high-tech solutions are not required to achieve greater energy-efficiency. Simple solutions such as flexible energy solutions, sun shading, natural ventilation, improved insulation of the building envelope, use of recycled materials, and building design considerations all can be effective.
Even better results can be achieved if more sustainable construction system solutions are used, such as intelligent lighting and ventilation systems, low temperature heating and cooling systems and energy saving household appliances.
In addition to a greater use of relevant energy saving technologies, the report stresses the importance of appropriate government policies on building codes, energy pricing and financial incentives that encourage reductions in energy consumption.
Approaches to finding building solutions will vary around the world. In developed countries the main challenge is to achieve emission reduction among mostly existing buildings, and this can largely be done by reducing the use of energy. In other parts of the world, especially places like China where almost two billion square meters of new building space is added every year, the challenge is to leapfrog directly to more energy-efficient building solutions.