MANILA, Philippines?From 8:30 p.m. to 9:30 p.m. on Saturday, darkness will blanket the Philippines as more than 2,000 groups and millions of individuals back the staging of Earth Hour in the country.

"The commitments of support grow with each day. We urge everyone to spread the word and join millions throughout the world by switching off lights from 8:30 to 9:30 p.m. on Saturday night, March 28,? Earth Hour national director Yeb Sano said in a statement.

"It is hoped that this global gesture will send a clear message for world leaders to take strong and decisive action against climate change,? he added.

For this year?s Earth Hour, the target is to have 10 million people, 500 corporations and 100 cities turn off their lights for an hour on Saturday.

Last year, more than one million Filipinos, 400 establishments and 50 cities participated in the activity ? resulting in a reduction of 56 megawatts (MW) in power consumption in the Luzon grid, according to data from the Philippine Electricity Market Corp., the operator of the wholesale electricity spot market.

With last year?s Earth Hour, the actual consumption in Metro Manila between 8 p.m. and 9 p.m. hit 2,675 MW, falling short of the projected demand of 2,691 MW.

In the Luzon grid, actual consumption was just 5,644 MW, 56 MW lower than the projected 5,700-MW demand.

The maximum demand drop of around 39 MW was experienced at 8:14 p.m. in Metro Manila and of around 116 MW at 8:34 p.m. in the Luzon grid.

With more individuals and groups expected to participate in this year?s activity, consumption from 8:30 p.m. to 9:30 p.m. should drop more significantly than last year?s.

Globally, Earth Hour is expected to have 1 billion people switching off their lights in 1,000 cities on March 28 on their respective time zones. This should signify "one global voice for action on climate change in 2009,? according to a fact sheet from the Worldwide Fund for Nature (WWF).

The main switch-off ceremony for Earth Hour in the Philippines will take place at the SM Mall of Asia globe starting 7 p.m., broadcast live on Studio 23.

Switch-off ceremonies will also be held throughout key cities in the country, including Makati, Baguio, Cebu and Davao.

Earth Hour is spearheaded in the Philippines by WWF, the Department of Energy, Switch Movement, Green Army and Earth Day Network.