The Earth Hour event will see thousands of Sydney businesses switch off their lights from 7.30pm to 8.30pm on Saturday, March 31, to highlight the need for action on global warming.

The event is organised by environment group, WWF Australia, which has set a target to cut Sydney’s greenhouse gas emissions by 5% in the 12 months to March 31 next year.

As well as turning off its own lights, AGL has pledged to pay to offset the greenhouse gases emitted by the electricity generated for all its 180,000 customers in NSW for the entire 24-hour period.

“We will make sure that AGL customers’ electricity usage in NSW on Saturday will be effectively 100% greenhouse neutral,” managing director Paul Anthony said.

“For a typical day in March, this equates to offsetting more than 4300 tonnes of carbon dioxide – the equivalent of taking almost 1300 cars off the road for a year.”

It follows a commitment by AGL last week to slash its own emissions by at least 6% by 2010 upon joining the Chicago Climate Exchange, the world’s first voluntary and legally binding greenhouse gas emissions reduction, registry and trading program.