Expansion Co-Planning of Integrated Electricity-Heat-Gas Networks in District Energy Systems

Since the linkages between electrical, gas and heat networks are becoming tight due to the penetration of coupling components like Combined Heat and Power (CHP), gas boilers, heat pumps and so on, it is vital to co-plan the expansion of electricity transmission lines, gas pipelines, heat pipelines and coupling components in district energy systems. The proposed co-planning process is modelled as a mixed integer non-linear programming problem which is solved by differential evolution (DE) algorithm. For each expansion co-planning, different scenarios are generated by the Monte Carlo (MC) simulation in order to reflect random system characteristics. The N-1 criterion is applied to measure the system security and the expected unserved energy (EUE) will be used to measure the system reliability. Meanwhile, the integrated electrical, heat and gas flow equations will be solved by a Newton-Raphson approach. The proposed co-planning model is demonstrated with a specific application to a real electricity-heat-gas system on the campus of the University of Manchester.