EARTH HOUR, dubbed "the biggest voluntary power down in history", has won a national environment award for its success in raising awareness of climate change.

The joint venture of Fairfax Media, the publisher of the Herald and the conservation group the World Wildlife Fund was awarded the gold Banksia Award at a ceremony in Melbourne on Friday.

The Deputy Prime Minister, Julia Gillard, and the Environment Minister, Peter Garrett, attended the awards, which recognised environmental excellence, sustainability and education.

About 50 million people around the world participated in Earth Hour 2008 by switching off their lights for an hour - acknowledging that the contribution of individuals can help tackle one of the biggest issues facing the planet.

Earth Hour's director, Andy Ridley, said the award was a great honour.