Optimized Scheduling of Multi-Region Gas and Power Complementary System considering Tiered Gas Tariff

Abstract Integrated Energy System (IES) based on Combined Cooling, Heating and Power (CCHP) technology has been proved as an efficient approach, which can resolve energy and environment issues and meanwhile bring economic benefits. For areas with fragile grid infrastructure and abundant oil, gas and renewable resources, various types of energy sources can complement each other and be cooperated as a unity, by operating the energy networks across regions as a single IES through the implementation of multi-region Gas and Power Complementary (GPC) system. Conventionally, the typical optimized scheduling of GPC system does not consider the complementarity among areas with diverse device and load characteristics. Since changes and developments have occurred in power-to-gas conversion technologies and intra-regional CCHP system, traditional models need to be updated and improved along with the application of tiered gas price. Based on the existing coupled power-gas flow scheduling model, this paper proposed a multi-region optimized scheduling model where the CCHP systems operate inside a region and power-gas complementarity could be achieved among multiple regions. Mixed Integer Linear Programming (MILP) was used to obtain the optimal solution of this scheduling model. The compressor linearization model was applied in order to describe transmission loss of gas network and perfect the power-gas flow model as well. Results of cases proved that considerable environmental benefits could be achieved when Combined Heating and Power (CHP) equipment was introduced in the multi-region GPC system. Finally, combined with the tiered gas tariff, the total operation cost of regions could be reduced and the day-ahead economic optimized scheduling could be improved. It also showed that the operating parameters in each region express different sensitivity to gas price due to the flow constraints. Moreover, compared with battery energy storage systems, power-to-gas conversion technology would be more prospective because it could significantly boost the system operating efficiency.