Modeling Optimal Economic Dispatch and System Effects in Natural Gas Networks

Abstract

In this paper we present a modeling framework for analyzing natural gas markets, taking into account the specific technological issues of gas transportation. We model the optimal dispatch of supply and demand in natural gas networks, with different objective functions, i.e., maximization of flow, and different economic surpluses. The models take into account the physical structure of the transportation networks, and examine the implications it has for economic analysis. More specifically, pressure constraints create system effects, and thus, changes in one part of the system may require significant changes elsewhere. The proposed network flow model for natural gas takes into account pressure drops and system effects when representing network flows. Pressure drops and pipeline flows are modeled by the Weymouth equation. A linearization of the Weymouth equation makes economic analyses computationally feasible even for large networks. However, in this paper, the importance of combining economics with a model for pressure drops and system effects is illustrated by small numerical examples.

Dynamic Compressor Optimization in Natural Gas Pipeline Systems

“…compressor continuity: (9), (10) junction conditions: (13), (14) density & compression constraints: (8), (12) periodicity constraints: (17), (18) boundary parameters: (15) compressor power: (11)…”

“…For example, early studies [10,11] focused on optimizing steady-state gas flows, for which the state equations are algebraic relations. Recent efforts have scaled and improved optimization techniques for similar problems [12,13,14,15,16]. In short-term operations, the operating setpoints for gas compressor stations can be readily changed, and compressor optimization for steadystate flows has been solved in the form of an optimal gas flow (OGF) [14].…”

A tutorial review of complementarity models for decision-making in energy markets

“…Or transport costs can raise prices in importing regions. These spatial linkages can be quite complicated, as in load flow models for electric power [accounting in the most complex cases for reactive power, voltage, and frequency (Bautista et al 2006)] or pipelines for gas transport [which could account for, e.g., line packing and other dynamics (Midthun et al 2009)]. In such circumstances, prices at different locations diverge.…”

Costs and Constraints of Transporting and Storing Primary Energy for Electricity Generation

“…A custom solution algorithm based on structural properties of Karush-Kuhn-Tucker (KKT) systems was proposed. Midthun et al [38] were the first to include physical features of the gas network in analysis of natural gas markets. With multiple objectives such as maximizing social surplus and consumer surplus and constraints accounting for gas pressure requirements, this paper illustrated the importance of combining economics with system effects implied by the physical structure of the network.…”