Sir David Attenborough has called for a "moral" crusade against wasting energy.
Sir David, 80, the presenter of the Planet Earth television series, told a Commons committee the wartime slogan "Waste Not, Want Not" should be used to persuade homeowners to switch off electrical appliances instead of leaving them on standby.
"I grew up during the war and it was a common view that wasting food was wrong," said Sir David. "It was not that you thought you were going to defeat Hitler by eating a little bit of gristle but that it was actually wrong to waste food. There should be a moral view that wasting energy is wrong," he added.
Sir David said he was convinced global warming caused disasters such as Hurricane Katrina. "I have just come back from Australia. People accustomed to living in hot temperatures in the Outback are saying, 'It has never been like this'."
He said climate change was a "political hot potato" but he was glad it was being grasped. He refused to be drawn on whether Gordon Brown had gone far enough with his pre-Budget report in tackling climate change.
The Environment, Food and Rural Affairs select committee is investigating how the public can do more to combat climate change.