Methods to solve natural gas loadflow problems using electric loadflow techniques are presented. The motivation is to integrate a natural gas network with an electric power transmission network so that the network analysis for a combined natural gas and electric power distribution network can be performed in a consistent manner. The issues arising from solving gas loadflow problems are discussed for the sake of electrical engineers. The application method and related issues are demonstrated through a case study on a gas network with compressors.

In this paper, the combined natural gas and electric optimal power flow (GEOPF) problem is presented. It shows fundamental modeling of the natural gas network to be used for the GEOPF, and describes the equality constraints, which describe the energy transformation between gas and electric networks at combined nodes (i.e., generators). We also present the formulation of the natural gas load flow problem, which includes the amount of gas consumed in compressor stations. Case studies are presented to show the sensitivity of the real power generation to wellhead gas prices. Results from the simulation demonstrate that the GEOPF can provide social welfare maximizing solutions considering both gas and electric networks.