China's emissions of carbon dioxide fell last year for the first time in 13 years - a drop of 2 percent during a year when their GDP was still growing by 7.4%. This decoupling of economic growth from emissions is significant and should buoy clean energy efforts around the world.

Another sign that efforts to control pollution are gaining traction is the rate of greenhouse gas emissions worldwide in 2014. For the first time in 40 years, carbon emission rates did not rise over the previous year during a time when economies continued to grow, according to new data from the International Energy Agency.

"This gives me even more hope that humankind will be able to work together to combat climate change, the most important threat facing us today," Fatih Birol, the IEA's chief economist, said in the IEA report.

One reason for the encouraging numbers is China's shift away from coal toward cleaner sources of energy. China led the world in renewable energy construction last year with $89.5 billion invested, a third of all dollars spent globally. At the same time, its domestic coal production is falling - down 2.9 percent over 2o13 - and the nation is focused on energy efficiency.

Solar is also showing impressive gains worldwide, according to a new market report by the Advanced Energy Economy, an association for clean energy companies. It shows that green energy is also earning plenty of money for the companies pursuing it. "Solar PV churned an estimated $90.3 billion in revenue with more than 10.0 GW each installed in China and Japan, and nearly 7 GW in the United States."

China's growth in 2014 slowed somewhat from 7.7 percent in 2013 to 7.4 percent in 2014.

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