Reliability Model of Joint Electricity and Natural Gas System Considering Electric Compressor Failures under Different Network Topologies

Abstract

We formulate a steady-state operational model for natural gas and electric transmission that is capable of considering bi-directional interdependence. The electric transmission system depends on the gas transmission system to provide fuel to power plants for reliable operations. The gas transmission system depends on the electric transmission system to provide power for some compressors, which ensure sufficient gas deliverability. We illustrate our formulation using a gas-grid test system with realistic properties, that is based on the topology of these networks in the northeastern part of the United States and Canada. Subjecting this test system to failures involving both natural gas and electric transmission demonstrates that having a larger fraction of electric-driven gas compressors (which rely on the power grid) worsens the impact of contingencies, relative to having compressors that use natural gas and on-site engines to run. The extent of this impact is sensitive to both the spatial pattern of gas-fired generation in the power grid, and the spatial distribution of electrified compressors in the gas transmission grid.