iONiUM writes "Last year, greenhouse gas emissions rose to a record amount of 30.6 gigatons, according to estimates from the International Energy Agency. From an article at the Guardian: 'Professor Lord Stern of the London School of Economics, the author of the influential Stern Report into the economics of climate change for the Treasury in 2006, warned that if the pattern continued, the results would be dire. "These figures indicate that [emissions] are now close to being back on a 'business as usual' path. According to the [Intergovernmental Panel on Climate Change's] projections, such a path... would mean around a 50% chance of a rise in global average temperature of more than 4C by 2100," he said.'" jamie points out a recent report that the cost of solar cells has dropped about 21 percent this year, leading to predictions that solar power may become cheaper than nuclear and fossil power within five years.