Al Gore, Nobel laureate and former US vice president, has urged Americans to shift from electricity generated by fossil fuels to renewable energy within a decade.

Gore challenged Americans to "shoot for the moon" on Thursday, comparing the scale of the challenge to landing a man on the moon, a goal set by John F. Kennedy in the 1960s.

"I challenge our nation to commit to producing 100 per cent of our electricity from renewable energy and truly clean carbon-free sources within 10 years," Gore said.

"When president John F. Kennedy challenged our nation to land a man on the moon and bring him back safely in 10 years, many people doubted we could accomplish that goal," he said.

'Vested interest'

Gore said the shift to new energy sources was needed to ensure "the survival of the United States of America as we know it ... the future of human civilization is at risk," he said.

Critics say the shift to renewable energy could not be achieved by the US and that a decade is not a sufficient amount of time in order to make the transition.

However, Gore dismissed the critics as having "a vested interest in perpetuating the current system no matter how high a price the rest of us will have to pay," and said the shift is necessary in order to avert a disaster and halt climate change.

The chief obstacle to achieving 100 per cent renewable energy in 10 years was a dysfunctional US political system that panders to special interests, said Gore.

Americans need to change "not just light bulbs, but laws," he said.

Political will

Switching over to renewable energy would "cure our carbon addiction and stimulate the economy. It would be the turning point that is needed to lead the world to a stable climate," said James Hansen, director of the Nasa Goddard Institute for Space Studies.

"Responding to climate change requires the full engagement of national, state and local public officials, business executives, religious and community leaders, and every citizen," said Alden Hayden of the Union of Concerned Scientists.

"By uniting in this common purpose and mobilizing America's ingenuity and can-do spirit, we can rise to this challenge. We can revitalize our economy, increase our energy security, and do our part to cut global warming pollution, all at the same time," he said.

Jonathan Lash, head of the environmental think-tank, the world resources institute, said: "America has led every major technological shift in the last 100 years, and we can lead the next  one as well.

"The problem is not technology, it is political will," he said.

Gore, was awarded the Nobel Peace Prize last year along with the Intergovernmental Panel on Climate Change (IPCC), for his work on global warming.