Compared to 4,240 megawatts consumed for all of April 24, the hottest day this year, the short brownout used up 3,170 kilowatts, or 530 units less.

Carbon dioxide in the air for the six targeted areas, which slipped into brief darkness, was reduced by 143 tonnes, or 15 per cent compared to April 24, Governor Apirak Kosayodhin said.

More than two million households had cooperated by turning off non-essential lights, which was more than expected, he said.

"I hope this campaign, which is observed on the ninth of every month, will go on, and not be just a one-off yesterday," he added.

The campaign has been heralded as a way to mitigate global warming by reducing the city's excessive energy consumption, which contributes to the problem of climate change.

The six critical thoroughfares are Khao San, the backpackers' haven, Yaowarat in Chinatown, Silom in the financial district, Ratchadaphisek and its entertainment strip, New Phetburi and its commuter gridlock and Rajprasong, the hub for tourism and shopping.

Bangkok is a major source of greenhouse gases in the country, as 30-50 per cent of total energy consumption is concentrated there. Statistics show that last year Bangkok residents devoured 206 million kilowatts of electricity, 34 million litres of oil, 400,000 litres of gasohol and 25,000 kilograms of natural gas.

The Bangkok Metropolitan Administration has initiated extended projects to reduce energy consumption, including free distribution of 50,000 energy-efficient fluorescent bulbs, commonly called "thin bulbs", to vendors and households as replacements.

Five million "thin bulbs" will later be sold citywide with the help of the BMA's promotional campaign. Another project is to plant a million trees in public parks and public areas across the capital by August 12 - the birthday of Her Majesty the Queen and celebrated as Mother's Day.

Saichai Kirdmongkon

The Nation