Building sector can play key role in combating global warming, UN report says

29 March 2007

The right mix of appropriate government regulation, greater use of energy saving technologies and behavioural change can substantially reduce global-warming carbon dioxide (CO2) emissions from the building sector, which accounts for 30 to 40 per cent of total energy use, according to a United Nations reported released today.

“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,” UN Environment Programme (UNEP) Executive Director Achim Steiner said of the measures that range from revamping ventilation systems to replacing the traditional incandescent light bulb.

“By some conservative estimates, the building sector worldwide could deliver emission reductions of 1.8 billion tonnes of C02. A more aggressive energy efficiency policy might deliver over 2 billion tonnes or close to three times the amount scheduled to be reduced under the Kyoto Protocol,” he added, referring to the pact setting legally binding emission reduction targets for 35 industrialized countries in the 2008-2012 period.

The report – Buildings and Climate Change: Status, Challenges and Opportunities – produced by UNEP’s Sustainable Construction and Building Initiative (SBCI), pushes for greater use of existing technologies like thermal insulation, solar shading and more efficient lighting and electrical appliances.

In the lifetime of an average building most energy is consumed not for construction but for heating, cooling, lighting, cooking and ventilation. Typically more than 80 per cent of total energy consumption occurs during use and less than 20 per cent during construction. Citing the example of Europe, the report says more than one fifth of present energy consumption and up to 45 million tonnes of CO2 per year could be saved by 2010 by applying more ambitious standards to new and existing buildings.

“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,” Mr. Steiner said, noting that several countries, including Australia, Cuba and the European Union, are looking to phase out or ban the traditional incandescent light bulb that has been around for well over a century in various forms.

The International Energy Agency estimates that a total global switch to compact fluorescent bulbs would, in 2010, deliver C02 savings of 470 million tonnes, or slightly over half of the Kyoto reductions.

“We have to ask what the hurdles are, if any, to achieving such positive low cost change and set about decisively and swiftly to overcome them, if they exist at all,” Mr. Steiner said.

SBCI Chairman Olivier Luneau added that advanced and expensive high-tech solutions were often not needed. “Simple solutions can include sun shading and natural ventilation, improved insulation of the building envelope, use of recycled building materials, adoption of the size and form of the building to its intended use, etc,” he said.

“Of course you can achieve even better results 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.”

The report stresses the importance of appropriate government policies on building codes, energy pricing and financial incentives that encourage reductions in energy consumption.

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 2 billion square meters of new building space is added every year, the challenge is to leapfrog directly to more energy efficient building solutions, the report says.