Investment in renewable energy infrastructure is outstripping that for fossil fuels.
Investment was equal in 2008, but the balance has swung since.
During 2011, globally, $40 billion was invested in fossil fuels.
$260 billion was invested in renewables.
In the past year the price of photo voltaic cells has dropped by 50%.
Peter Newman describes the growth of investment in renewable as exponential.
He says we are living through one of the most dramatic periods in history as fossil fuels are being phased out.
Peter Newman is Professor of Sustainability, Curtin University, Perth Western Australia: