The transition to more sustainable technologies and approaches to meet industrial heating demand is crucial for achieving ambitious environmental goals. Industrial waste heat recovery solutions are one of the key technologies with considerable potential to contribute to energy decarbonization in heating systems. Theoretical and experimental studies revealed that a significant amount of waste heat could be recovered from electrolysis. A feasibility study was conducted to estimate the integration of waste heat from food industry and electrolyser into a district heating system, which would provide heat to industrial buildings with low energy intensity. According to the results of this study, waste heat recovery from industries and electrolysis have tremendous potential to contribute to sustainable industrial processes. Because isolated industrial parks with various energy intensities are common, the findings of this research may be useful for improving energy efficiency through the integration of waste heat-based small district heating networks.