4th generation nuclear power plant with capacity of 35 billion kWh/year

China's Shidaowan High Temperature Gas-Cooled Reactor Plant will integrate a pressurized water reactor to increase its capacity, helping to provide electricity to 17 million households.

Generation 4 nuclear power plant in Shandong province. Photo: CGTN

China has begun expanding the world's first fourth-generation nuclear power plant, the Shidaowan High-Temperature Gas-Cooled Reactor (HTGR) in eastern China's Shandong Province, Interesting Engineering reported on July 29. The self-developed project is located in Rongcheng County, Weihai City. China Huaneng Group, Tsinghua University and China National Nuclear Corporation are jointly developing the project.

Equipped with the world's first high-temperature gas-cooled reactor, the plant began commercial operation last December. Zhang Aijun, vice president of HTGR Nuclear Power Company, said the first phase of the expansion project involves installing two domestically produced third-generation pressurized water reactors, Hualong One, to operate in parallel with the gas-cooled reactor, each with a capacity of 1.2 million kilowatts. When completed, the plant is expected to produce 20 billion kilowatt hours of electricity per year, increasing the thermal energy supply area by 20 million square meters, benefiting 600,000 local residents.

According to Zhang, the plant will add four more pressurized water reactors in the second expansion phase, each with a capacity of more than one million kilowatts. The completed plant will have a total installed capacity of more than 5 million kilowatts, with an annual production capacity of 35 billion kilowatt hours, enough to meet the electricity consumption of more than 17 million three-person households for a year. The project will reduce the consumption of 11.5 million standard tons of coal and eliminate 27.6 million tons of carbon dioxide emissions each year.

"We will maximize the impact of the third-generation pressurized water reactor and the fourth-generation high-temperature gas-cooled reactor integrated in large facilities, further enhancing China's nuclear power equipment manufacturing, construction, operation and maintenance capabilities," Zhang said.

Zhang Yijin, an operations manager at the power plant, said in January that one of the key features of the Generation 4 reactor is that the nuclear fuel comes in the form of small tennis ball-like spheres. Each reactor contains up to 430,000 fuel spheres. They are 6 centimeters in diameter, and contain 12,000 millimeter-sized fuel particles inside. The particles contain a very small fuel core and four ceramic shells, according to Tong Liyun, another operations manager at the plant. The entire ceramic shell can withstand very high temperatures. Under any operating conditions, the temperature of the fuel sphere will not exceed the temperature that the ceramic shell can withstand. This design ensures that radioactive materials will not leak.

Each sphere has the energy equivalent of 1.5 tons of coal and does not require a temporary shutdown of the reactor for refueling, ensuring continuous operation. The operating reactor is cooled with inert helium gas instead of water. It also uses a passive waste heat removal system, which is key to the safety of the plant. Construction at HTGR HTGR began in 2012, with grid connection in 2021 and commercial operation in 2023.