Cascading of Fluctuations in Interdependent Energy Infrastructures: Gas-Grid Coupling

TL;DR

This paper investigates how fluctuations from renewable wind energy impact natural gas pipeline pressure stability, revealing that pressure deviations grow over time and are most significant at flow reversal points, affecting energy infrastructure reliability.

Contribution

It introduces a PDE-based model to analyze the effects of wind-induced fluctuations on natural gas pipeline pressure dynamics, highlighting potential reliability concerns.

Findings

Pressure fluctuations grow linearly over time.

Maximum pressure deviations occur at flow reversal points.

Wind variability influences pipeline pressure stability.

Abstract

The revolution of hydraulic fracturing has dramatically increased the supply and lowered the cost of natural gas in the United States driving an expansion of natural gas-fired generation capacity in many electrical grids. Unrelated to the natural gas expansion, lower capital costs and renewable portfolio standards are driving an expansion of intermittent renewable generation capacity such as wind and photovoltaic generation. These two changes may potentially combine to create new threats to the reliability of these interdependent energy infrastructures. Natural gas-fired generators are often used to balance the fluctuating output of wind generation. However, the time-varying output of these generators results in time-varying natural gas burn rates that impact the pressure in interstate transmission pipelines. Fluctuating pressure impacts the reliability of natural gas deliveries to those same generators and the safety of pipeline operations. We adopt a partial differential equation model of natural gas pipelines and use this model to explore the effect of intermittent wind generation on the fluctuations of pressure in natural gas pipelines. The mean square pressure fluctuations are found to grow linearly in time with points of maximum deviation occurring at the locations of flow reversals.