State Power Investment Corp said its demonstration district heating system, NuanheOne, was put into operation on Tuesday and will cover Haiyang city of Shandong province and benefit 200,000 local residents with clean heating, making Haiyang the country's first zero-carbon city.

The system extracts non-radioactive steam from the secondary circuit of the two Haiyang AP1000 units, which is then fed through a multi-stage heat exchanger in an on-site heat exchange station.

The heat is then fed to an off-site heat exchange station belonging to a local thermal company, where heated water flows through municipal heating pipes to consumers.

Unit 1 and Unit 2 of the Haiyang Nuclear Power Plant in China's Shandong province have produced more than 60 billion kilowatt-hours so far. Unit 1 of Haiyang NPP is the world's largest cogeneration unit and has replaced 12 local coal-fired boilers, reducing a coal equivalent of 100,000 tons each heating season.

According to SPIC, the use of nuclear energy heating is expected to cut emissions of carbon dioxide by 180,000 tons, emissions of soot by 691 tons, emissions of sulfur dioxide by 1,188 tons and emissions of nitrogen oxide by 1,123 tons.