Construction of six to eight nuclear reactors will commence in 2018, raising China's total nuclear generating capacity by 6 gigawatts, the National Energy Administration said on Wednesday.

China will also finish two delayed third-generation reactor projects in 2018, including the world's first Westinghouse AP1000 in the Sanmen nuclear power plant in Zhejiang province and the first unit of the Taishan European Pressurized Reactor project designed by Areva in Guangdong province.

An analyst said with no new reactor project approved in the country for more than two years, China might not be able to accomplish its 2020 targets.

Joseph Jacobelli, a senior analyst of Asian utilities at Bloomberg Intelligence in Hong Kong, said the approval of six to eight reactors is expected, as China should be approving a minimum of six reactors per year.

"However, it is unlikely that by 2020 China will have commissioned 58 GW," said Jacobelli. "But it will be shifted forward so that China would still end up with 88 GW or more before 2025."

China vows to raise its total installed nuclear capacity to 58 GW by 2020, up from 35.8 GW at the end of 2017.

It also aims to have another 30 GW under construction by the end of 2020.

The country also plans to speed up preparation work for the country's third phase of State oil reserves storage construction this year.

According to the administration, China will produce about 160 billion cubic meters of natural gas, a record high and up 8.5 percent from 2017, while domestic coal production in 2018 will also reach an all-time high at 3.7 billion metric tons, up 7.3 percent from 2017.

Coal consumption will be cut to about 59 percent of the nation's primary energy mix while natural gas consumption will be raised to 7.5 percent of the mix in 2018, it said.