President-elect Barack Obama has plans to invest $150 billion in clean energy technology over the next 10 years. With similar initiatives in other countries, when might we expect exciting alternative technology to deliver true energy independence?
The predictions are all over the map.
"This goal is achievable, affordable and transformative," he said.
Many others think it will take longer.
The European Renewable Energy Council and Greenpeace recently released their Energy [R]evolution Report, in which they predict renewables will need more like 80 years to completely replace fossil fuels.
"Al Gore can say 10 years because he is Al Gore," said Sven Teske of the Greenpeace International renewable energy campaign. "We can actually back up our targets."
In their report, Teske and his fellow authors asked the renewable energy industry what it thought it could deliver with proven technologies. This renewable potential was then matched up against economic growth predictions.
To stimulate the turnover in energy supply, governments will need to agree to ambitious reductions in greenhouse gas emissions, Teske told LiveScience.
However, he admits that it's a two-way street. Environmental groups and the renewable industry need to provide politicians with reasonable roadmaps for cutting carbon out of the energy equation.
"We hope we have some positive influence in making it easier for politicians to agree on tough emission reductions," Teske said.
Here is what the future may hold if roadmaps, predictions and policy targets all come true.
World leaders meet in Copenhagen, Denmark, to design a follow-up to the Kyoto Protocol.
All new homes built in Germany have renewable energy heating systems.
5.2 percent reduction in greenhouse gas emissions emissions from 1990 levels is achieved by those countries that signed the Kyoto Protocol.
20 percent of California's electricity comes from renewables.
Toyota releases a plug-in hybrid electric vehicle.
The London Olympics is a low-carbon, zero-waste games.
No more incandescent bulbs sold in the United States, as proscribed by 2007 Energy Bill.
100 percent of U.S. electricity comes from solar, wind and other renewables (Gore's prediction).
$255 billion spent per year (more than four times what is currently spent) on biofuels, wind power, solar photovoltaics, and hydrogen fuel cells, according to market research firm Clean Edge.
$150 billion invested by this date by the U.S. government on climate-friendly energy development (Obama's plan).
All new cars are hybrids, according to an anonymous survey of car industry executives by IBM's Institute for Business Value.
35 miles per gallon is average for the U.S. fleet.
20 percent of the European Union's energy comes from renewables.
15 percent of China's energy comes from renewables.
Sweden is oil-free.
36 billion gallons of biofuels sold in the United States, up from 4.7 billion gallons in 2007.
25 percent of U.S. electricity comes from renewables (Obama's plan).
50 percent increase in world energy demand from 2005 levels, according to U.S. Department of Energy (DOE).
All new federal buildings are carbon-neutral, as stated in 2007 Energy Act.
70 percent of Hawaii's energy comes from renewables, thanks in part to a ban on new coal plants.
One-fifth of U.S. power comes from wind, the DOE predicts.
One-fourth of U.S. workers wear a green collar, according to the American Solar Energy Society.
20 million new jobs created by renewable industry, says United Nations report.
50 percent of the world's energy comes from renewables, claims the Energy [R]evolution Report.
100 percent of the world's energy comes from renewables, claims the Energy [R]evolution Report.