Calculation and analysis of energy storage in heat supply nets of distributed energy

Highlights: • A new model is proposed for the calculation of energy storage in the heat-supply net. • The proposed method introduced an influence θ to the improved HTES model. • The new method connected the energy stored in the heat-supply net with users indirectly. • The performance of the proposed model is tested using several cases. • The new model can guide the temperature and flow rate of the supply water in practice. The study of energy storage characteristics of heat-supply net in distributed energy system is essential to develop the control strategy of energy efficient utilization. Studying the energy storage characteristics of the heating network in the distributed energy system is the key to formulating energy-saving utilization control strategies. In this paper, the quantitative calculation model of heat transfer and energy storage (HTES) is established through the research on the energy storage characteristics of heat-supply net in distributed energy system, and the duration of thermal storage energy (TSED) of the energy storage characteristics in heat-supply net is also described. In the HTES model, the influence factor is introduced to make the temperature of the heat transfer section in the initial model more realistic, which also improves the accuracy of the model. Based on the HTES model and experimental data, the lag time of the three heat exchange stations was calculated and compared to verify the correctness of the HTES model. Through the calculation of practical cases, the TSED is obtained and analyzed, and for a best flow rate is found for the working medium. In addition, the quality and quantity regulation of central heating network under the conditions of unit shutdown and time-divided heating is calculated to achieve the purpose of guiding the actual water supply temperature and flow.