Joint Economic Dispatch of Integrated Electricity-Gas Energy System and Double-track Freight Railway Network

Although the transportation tends to serve as flexible loads to smooth the energy demand profile, the transportation capacity is far from fully exploited to promote the efficiency of energy systems. Railways can transport a large volume of liquefied natural gas (LNG) to natural gas networks, providing an alternative to pipelines. Motivated by this idea, this paper interconnects integrated electricity-gas energy systems (IEGES) with double-track freight railway networks (DTFRN) and proposes a joint economic dispatch model for integrated railway-electricity-gas systems (IREGS) considering railway operation requirements. The model is formulated into a solvable mixed integer linear programming by applying the piecewise linear approximation method on Weymouth equation. Simulations tested on a modified IREGS system proves the effectiveness of the dispatch model. The results show that the DTFRN is of benefit in reducing the amount of compressor-consumed gas and enhancing the gas peaking capacity, and therefore it lowers the operation cost of the IREGS.