Chengde district heating system 

With the objective of improving the environment in Chengde significantly, a new district heating system based on surplus heat from an existing power plant was planned. COWI has carried out an evaluation of the proposed layout and design of the new 700 MW district heating system in Chengde supplying a heat area of 11 million m². The assistance included improvement and optimisation of the energy efficiency of the system and minimisation of the needed investments.

In connection with construction of a new district heating transmission pipeline from the existing power plant, COWI has performed transient and steady-state hydraulic analyses of the district heating network and transmission pipeline. The objective of the analysis was to evaluate safety aspects of the new transmission pipe and major technical challenges have been addressed, i.e. a detailed evaluation on how the great elevation differences should be addressed in an appropriate manner, an evaluation of pump trip and valve closing in order to avoid damaging water-hammering in the system etc.

Finally, the work has included specification of functional requirements to major components such as valves, pumps, control system, etc. regarding the new lay-out of the system.