Renewable energy includes non-fossil fuels such as wind and solar power, hydropower, biomass, geothermal and ocean energy.
The law, which took effect in January 2006, was aimed at promoting the use of renewable energy, increasing energy supply, safeguarding energy security and protecting the environment.
It covered pricing management and supervision measures.
Premier Wen Jiabao told the Copenhagen Climate Change conference on Friday that between 2005 and 2008, renewable energy increased by 51 percent in China, representing an annual growth rate of 14.7 percent.
Wen said in 2008, the use of renewable energy reached an equivalent of 250 million tons of standard coal.
"A total of 30.5 million rural households gained access to bio-gas, equivalent to a reduction of 49 million tons of carbon dioxide emissions," he said.
Signaling an official effort to shore up clean energy development and fight climate change, the law required the government set up a special fund to support renewable energy scientific research, finance rural clean energy projects, build independent power systems in remote areas and islands, and build information networks to exploit renewable energy.
The fund will be managed by finance, energy and pricing sectors of the State Council.
The draft amendment stated that the government should make national development plans for renewable energy, involving grid construction, services and supporting measures.
China made a national plan on renewable energy in 2007.
The draft also said grid companies should sign agreements with certified renewable energy power generation enterprises, and buy all the power up to the standard.
The renewable energy power generation enterprises were obliged to assist the grid companies to ensure network security, it said.
In 2008, China used more hydro and solar power than any other country and its use of wind power ranked fourth.