CNNC completes design of district heating reactor

07 September 2018

The preliminary design of the Yanlong swimming pool-type low-temperature reactor for district heating has been completed, China National Nuclear Corporation (CNNC) announced yesterday.

A model of the Yanlong reactor (Image: CNNC)

CNNC launched its independently researched and developed Yanlong reactor (referred to as the DHR-400) for district heating in November 2017. The move came shortly after the "49-2" pool-type light-water reactor developed by the China Institute of Atomic Energy continuously supplied heat for 168 hours.

CNNC said the Yanlong reactor - which an output of 400 MWt - has been developed based upon the company's safe and stable operation of pool-type experimental reactors over the past 50 years. It said the Yanlong is a "safe, economical and green reactor product targeting the demand for heating in northern cities". The reactor can be operated under low temperatures and normal pressures. It can be constructed near urban areas due to the zero risk of a meltdown and lack of emissions. In addition, the reactor is easy to decommission. The Yanlong "represents a relatively modest investment", according to CNNC.

"It's an effective way to improve China's energy resource structure by utilising nuclear energy for district heating, and to ease the increasing pressures on energy supplies," CNNC said. "Nuclear energy heating could also reduce emissions, especially as a key technological measure to combat haze during winter in northern China. Thus, it can benefit the environment and people's health in the long run."

The company added, "It can be constructed either inner land or on the coast, making it an especially good fit for northern inland areas, and it has an expected lifespan of around 60 years. In terms of costs, the thermal price is far superior to gas, and is comparably economical with coal and combined heat and power (CHP)."

The Chinese government has made clean-energy heating a priority. Last year, the authorities issued guidance on clean heating in winter in northern China. The National Energy Administration released a five-year plan, covering 2017-2021, highlighting the innovation of clean heating technology and consideration of nuclear heating.

Research work in China on the possible application of nuclear heat began in the early 1980s. During 1983-1984, the Institute of Nuclear Energy and Technology (INET) at Tsinghua University used its existing pool-type test reactor to provide space heat for nearby buildings. Meanwhile two types of nuclear heating reactors - one a deep pool type, the other a vessel type - were developed by INET. The vessel type reactor was selected as the main development direction. Construction of a 5 MWt experimental nuclear heating reactor (NHR5) at INET began in 1986 and was completed in 1989. The larger, demonstration-scale NHR200-II was developed from this.

A feasibility study on constructing China's first nuclear plant for district heating is being carried out by China General Nuclear and Tsinghua University. The plant would use the domestically-developed NHR200-II low-temperature heating reactor technology.

Small modular reactors (SMRs) will be used in the future not just for electrical generation but also for providing heating, Mingguang Zheng - president of Shanghai Nuclear Engineering Research & Design Institute and senior vice president of State Nuclear Power Technology Company - said today at the World Nuclear Association Symposium 2018.

He said China's current use of fossil fuels to provide heating creates very serious air pollution during the winter months. "To prevent air pollution and to enhance human life, we think that nuclear power, especially the use of nuclear energy to supply district heating, is very important," Zheng said.

Researched and written by World Nuclear News