Research on energy management of integrated energy system coupled with organic Rankine cycle and power to gas

Abstract

Integrated energy system could offer multiple products, such as heat and power. However, the supplied energy and thermoelectrical ratio may not conform with the demand and or thermoelectrical ratio of end user. In order to solve the energy mismatch between source side and load side an integrated energy system coupled with organic Rankine cycle and power to gas was constructed, and energy management strategies based on organic Rankine cycle and power to gas were proposed. Considering the economic, energy and environmental performance of the system, the evaluation index and multi-objective optimization model were constructed, respectively. Then, a case study of an industrial park including factory, dormitory and commercial buildings was employed and the hourly heating, electrical and gas loads were simulated. Finally, the capacity configuration optimization, system performance of integrated energy system under four strategies: without organic Rankine cycle and power to gas, with power to gas, with organic Rankine cycle and with organic Rankine cycle and power to gas were compared. Simultaneously, the suitable integrated energy system configuration between different thermoelectrical ratio range of end user was analyzed. Results showed that when organic Rankine cycle and power to gas were added to integrated energy system, the output range of thermoelectrical ratio could be widened. When thermoelectrical ratio was less than 0.42, the comprehensive performance of integrated energy system coupled with organic Rankine cycle was the best. When thermoelectrical ratio was greater than 3.89, the comprehensive performance of integrated energy system coupled with power to gas was the best. Integrated energy system coupled with organic Rankine cycle and power to gas presented better performances if the thermoelectrical ratio was between 0.43 and 3.21.