THE world has just five years to make ''urgent and radical policy changes'' or lock in dangerous climate change, the world's leading energy agency has warned, sparking a debate about whether Australia should shift to gas or renewable energy.
The 2011 World Energy Outlook - released by the International Energy Agency late on Wednesday night - finds the world is on track to build enough fossil-fuel power stations, energy-intensive factories and buildings by 2017 to close the door on keeping climate change to a safe level.
The Greens seized on the report to warn the energy sector against investing in gas production, saying the sector would be taking ''a gamble'' building new gas plants when there was clearly an urgency to move straight to renewable energy sources. Energy Minister Martin Ferguson retorted that the Greens had ''completely misunderstood'' the report.
Advertisement: Story continues below
The outlook says coal consumption needs to peak well before 2020 if the world wants to halt global warming at a 2 degrees rise, which scientists say is needed to avoid the worst impacts of climate change.
If energy and climate policies currently proposed by all world governments - including Australia's carbon tax - are put in place, temperatures will rise by 3.5 degrees. If the world remains on its current path of growth in fossil fuels global temperatures will rise by 6 degrees, the outlook says.
Agency chief economist Fatih Birol said if by 2017 there is not a start to major new clean infrastructure investments ''the door to 2 degrees will be closed''.
''I am very worried,'' he said, ''if we don't change direction now on how we use energy, we will end up beyond what scientists tell us is the minimum. The door will be closed forever.''
The outlook comes as nations prepare to converge on the South African city of Durban later this month for the next round of global climate change negotiations, but there is almost no expectation significant progress on a global pact will be made.
The agency's report says emissions from existing fossil-fuel power plants, factories and buildings have already locked in 80 per cent of the emissions allowed by 2035 to keep carbon dioxide levels in the atmosphere to 450 parts per million, the maximum possible to keep temperature rises to 2 degrees. The other 20 per cent will be eaten up by 2017 on current development trends the outlook says.
Greens deputy leader Christine Milne told The Age the report showed that there was no longer time to use gas - which is a cleaner-burning fuel than coal - as a stepping stone to renewable energy such as wind, solar and geothermal. ''[The outlook] is basically saying to the investment community, 'You are going to be gambling on how long gas has got as any kind of transitional fuel'.''
Australia would need to make deeper cuts to keep to a 450ppm target, which would restrict the number of permits under the carbon-pricing scheme and make emissions more expensive.
However, Mr Ferguson told The Age: ''The flexibility of gas-fired technology and the fact it is the cleanest fossil fuel make it an attractive investment option.
''In addition to gas, the message I am getting firsthand out of China and India … is that coal-fired power will increase and Australia is well placed to supply coal to fuel their growing economies.''