Quantifying heat demand of China’s manufacturing by sub-sectors and temperature zones: a four-step accounting method

In 2020, the heat demand drove 54 % of the energy-related carbon emissions (ERCEs) in China’s industry, and the majority of the heat demand was in manufacturing. Due to the scale, numerous sub-sectors, and complex production processes of the manufacturing industry, together with insufficient data availability, a lack of comprehensive data for heat demand differentiating sub-sectors and temperature zones still exists. This study developed a four-step accounting method to fill this gap, including the selection of sub-sectors, identification of typical production processes, estimation of heat demand by temperature zones for each process, and calculation of the total heat demand by sub-sectors and temperature zones. 9 manufacturing sub-sectors were selected to estimate the heat demand between 0 and 1800 °C, and 16 production processes were identified to differentiate the heat demand by temperature zones. The results indicated that the temperature zones of 1601–1800 °C, 0–200 °C and 801–1000 °C account for 28.0 %, 20.4 % and 19.6 % of the total heat demand, respectively. Meanwhile, the high temperature zone was dominated by ferrous metals and non-metallics, the middle temperature zone was dominated by chemicals, ferrous metals, and non-ferrous metals, and the low temperature zone was diverse among all sub-sectors.