China is the world's largest coal consumer, and it also has become the biggest user of renewable energy. That's as the country works on using more alternative and clean energy in its economic development.

A fresh report from the Chinese Academy of Social Sciences says China's consumption of clean energy increased in 2015. And nearly 6 percent of the country's total energy consumption was natural gas. Experts say increased usage of natural gas can help reduce China's smog.

"We think a very effective way to improve the environment is to use natural gas. It's a high-quality energy with lower pollution. And at the same time, the supply of natural gas is currently sufficient in the world," said Li Ping, director of Inst. of Quantitative & Technical Economics, CASS.

China has the world's largest capacity for hydro, wind and solar power generation. But with limited infrastructure, many power plants are idle.

"The government should not only build power stations, but should also construct power distribution facilities, so that the electricity power by clean energy can be used efficiently," said Huang Xiaoyong, Chinese Academy of Social Sciences.

China plans to invest no less than 2 trillion yuan in the construction of power distribution networks in the next several years.