Statistical analysis of key indicators in district heating operations in northern China over the past five years

This study presents and applies a questionnaire-based systematic methodology for analysing the operational strategies and energy efficiency of district heating systems in northern China. By examining data from 144 heating companies covering approximately 42% of the urban heating area over five heating seasons (2017–2022), the study focuses on trends in key energy consumption indicators at both the heat source and network sides. The results indicate an overall decline in specific heat consumption on the heat source side, along with improved efficiency in both coal-fired and gas-fired boilers, albeit with notable regional disparities. On the network side, significant regional imbalances were observed in make-up water rates for both primary and secondary networks and in electricity consumption at heat exchange stations, highlighting acute infrastructure aging issues particularly in northeastern China.