Coordinated Expansion Planning of Gas and Electricity Networks Considering N-1 Security Criterion

Planning for the coordinated expansion of generation units, taking into account the fuel needed, has always attracted the attention of power industry planners. Failure to coordinated expansion of electricity and gas networks will result in excessive investment and, in some cases, defects in power supply. Therefore, there is a need to a model coordinating the expansion of electricity and gas networks, while taking into account the technical constraints. In this study, centralized expansion of gas and electricity networks is modeled by considering N-1 security criterion in gas network. This modeling is from the perspective of a central investor who, considering the technical constraints, seeks to minimize the total cost of investment and operation of the electricity and gas networks. The results of the gas network investment problem indicate that there is a need to increase pipeline capacity in some areas. In the proposed case study, the investment cost of the gas network is $19 million, while the total cost of investment and operation of the gas network is $37.19 billion. On the other hand, in the electricity grid, new power plants need to be installed in the designated areas. The results also indicate that the capacity of the F-H transmission line should be increased. Moreover, considering the N-1 criterion for gas pipeline outages, the power grid would prefer to install about 3200 MW of new generation units all around the grid thereby boosting the power network against pipeline outages. However, 2400 MW of new generating units would be adequate when N-1 criterion is omitted.