Modeling of third party access tariffs and portfolio gas purchases of CCGTs in the self-unit commitment problem

P. Otaola-Arca, J. García-González, F. Mariño, I. Rivera

IEEE Transactions on Power Systems Vol. 36, nº. 4, pp. 2771 - 2785

Summary:

The structure of the operational costs of gas fired units (GFU) in real power systems is much more complex than what standard unit-commitment (UC) models consider in the state-of-the-art formulations. On the one hand, when a generation company owning several GFUs procures its gas -either totally or partially- at the gas spot market, the final fuel price will depend on the total gas purchases. This fact couples the operation of all the GFUs as it is impossible to build individual cost functions for each generator. On the other hand, as any other gas consumer, the generation company has to pay the gas Third Party Access (TPA) tariffs. The generation company must contract in advance the monthly TPA capacity for each gas exit point and depending on such decision, the final variable cost of the GFUs will be different. This paper states the importance of modeling properly both issues and presents a novel mathematical formulation that can be embedded in a self-UC model. The presented example case highlights the benefits of the proposed formulation.

Spanish layman's summary:

Este paper presenta una formulación self-UC estocástica incluyendo Tarifas de Acceso de Terceros (ATR) a la red de gas y compras conjuntas de gas, detallando los costes de los CCGT. Además se compara con una formulación estándar para destacar la importancia de modelar estos costes de forma detallada.

English layman's summary:

This paper presents a stochastic self-UC formulation that includes Third Party Access (TPA) tariffs to the gas network and portfolio gas purchases for CCGTs cost modeling. A comparison with a standard formulation is presented to highlight the importance of modeling costs in a detailed manner.

Keywords: CCGT, electricity market, gas market, profit maximization, third party access (TPA), unit commitment (UC).

JCR Impact Factor and WoS quartile: 7,326 - Q1 (2021); 6,600 - Q1 (2022)

DOI reference: https://doi.org/10.1109/TPWRS.2020.3040677

Published on paper: July 2021.

Published on-line: November 2020.

Citation:
P. Otaola-Arca, J. García-González, F. Mariño, I. Rivera, Modeling of third party access tariffs and portfolio gas purchases of CCGTs in the self-unit commitment problem. IEEE Transactions on Power Systems. Vol. 36, nº. 4, pp. 2771 - 2785, July 2021. [Online: November 2020]