UNEP Says Greener Buildings Could Slow Global Warming
OSLO -- Better architecture and energy savings in buildings could do more to fight global warming than all curbs on greenhouse gases agreed under the U.N.'s Kyoto Protocol, a U.N. study showed on Thursday.
Better use of concrete, metals and timber in construction and less use of energy for everything from air conditioners to lighting in homes and offices could save billions of dollars in a sector accounting for 30-40 percent of world energy use.
"Buildings can play a key role in combating climate change," the U.N. Environment Programme said in a report issued in Oslo during a conference on ways to promote economic growth without damaging the environment.
Simple measures include more blinds to keep out the sun in hot climates, switching to energy efficient lightbulbs, better insulation and ventilation. "Avoid building a bigger house than you need," was among the tips.
"By some conservative estimates, the building sector worldwide could deliver emission reductions of 1.8 billion tonnes of carbon dioxide," said Achim Steiner, the head of UNEP. Carbon dioxide is the main greenhouse gas.
"A more aggressive energy efficiency policy might deliver over two billion tonnes or close to three times the amount scheduled to be reduced under the Kyoto Protocol," he said.
The U.N.'s Kyoto Protocol binds 35 industrial nations to cut missions of greenhouse gases, mainly from burning fossil fuels, by about 5 percent below 1990 levels by 2008-12 to slow a warming that may cause more heatwaves, droughts and rising seas.
But Kyoto has few incentives for more efficient buildings even though they are a big part of a problem also stoked by sectors such as transport and farming. The report urged global action to promote greener buildings.
"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," Steiner said.
GREAT WALLS OF CHINA
The report said fast-growing developing nations needed to focus on more efficient new buildings. China is the world's top builder, adding almost 2 billion square metres (21.53 billion sq ft) of new building space every year, it said.
"Typically construction costs increase by 3-5 percent due to the introduction of energy efficient solutions," it said. The UNEP study is part of a project also supported by companies such as Lafarge, Skanska and Arcelor.
The report said most energy used in buildings is during their lifetimes -- from heating to lighting -- rather than in construction. Overall, most energy is used by homes, ahead of shops, offices and other buildings such as schools or hospitals.
For builders, timber was often a cheaper and lighter-weight alternative for house frames than steel. Energy consumption in making steel was 2-3 times higher than in making glulam beams -- wood glued together and laminated for more strength.
It also recommended refurbishing old buildings rather than demolishing them and designing new buildings for long use.
The report also said there were other factors to keep in mind -- even gender. Some studies have shown women prefer higher room temperatures than men, even with similarly thick clothing.