Tom Leonard in New York
Last Updated: 6:01pm BST 09/09/2008
The United Nations has been attempting to cut global warming by raising the summertime temperature inside its New York headquarters and forcing occupants to wear lighter clothes.
A month-long experiment approved by the secretary general, Ban Ki-moon, to raise the thermostat throughout much of the building from 72 to 77 degrees was so successful that it may become a more long-term policy, said the UN.
Diplomatic dress codes were relaxed as many male staff got rid of their jackets and ties, and women chose sleeveless outfits. Temperatures in the often windowless conference rooms, where most of the negotiating goes on were set slightly lower at 75 degrees.
The initiative, designed to show the UN was serious about curbing energy use that contributed to global warming, saved about 30 million pounds of steam used in the glass-fronted 1952 building's cooling system.
A UN spokesman said this was the equivalent of 2,000 metric tons of carbon dioxide, or 710 transatlantic return flights.
"In view of these concrete results, the secretary general has decided to expand the Cool UN initiative until September 15," said the spokesman.
A similar wintertime project is already under discussion and officials believe they could save $1 million annually if the temperature changes throughout the year.
However, the thermostats will be on full when world leaders descend on the 39-storey building for their annual ministerial meeting later this month.
UN officials previously said that the deciding factor in whether the arrangement becomes permanent would be its effect on productivity.
Some diplomats welcomed a more uncomfortable room temperature if it discouraged colleagues from dragging out interminable and ultimately fruitless negotiations late into the evening.
However, others warned that diplomats without suits were not taken seriously and that warmer temperatures encouraged delegates' minds to wander, apparently making them less willing to compromise.