BEIJING -- China's largest grid operator said Tuesday that energy authorities might soon approve a plan to build 12 electricity transmission lines linking the coal production and hydropower centers in inland areas to the densely populated east.

With a total investment of more than 210 billion yuan (about $34 billion), the 12 major projects include four ultra-high-voltage alternating current (UHV AC) power transmission lines, five UHV direct current (DC) lines and three conventional 500-kilovolt networks.

Zhang Zhengling, a planning official with the State Grid Corporation of China (SGCC), said the lines will send electric power from Inner Mongolia, Shanxi, Shaanxi and Yunnan to Beijing, Tianjin and Hebei, as well as to two delta economic hubs along the Yangtze and Pearl rivers.

"The projects, considered important investment measures to stabilize economic growth, aim to ease power shortage in the east and alleviate the worsening smog problems in central and eastern regions," Zhang said.

If the National Development and Reform Commission, the top economic planner, and the National Energy Administration agree with the plan, all the projects are expected to start construction this year.

The SGCC, which supplies electricity to 80 percent of China's population, will be responsible for building 11 electricity transmission lines, while the China Southern Power Grid will construct the line distributing power from Yunnan to Guangdong, Guangxi, Yunnan, Guizhou and Hainan, which are home to some 230 million users.

As part of China's action plan to control air pollution, the projects will help cut thermal coal consumption by 200 million tonnes a year and reduce the density of PM2.5 pollutant particles by 4 to 5 percent in the central and eastern regions, the SGCC estimated.

The heavy investment could add another 90 billion yuan in output value for electricity equipment manufacturers, while bringing 500 billion yuan of investment to the power generating sectors, according to the SGCC.

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