"Greener" buildings could slow global warming: UNEP

By Alister Doyle, Environment Correspondent

OSLO (Reuters) - 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 metric tons 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 tons 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.