Improving Accuracy and Efficiency of Start-up Cost Formulations in MIP Unit Commitment by Modeling Power Plant Temperatures

TL;DR

This paper introduces a novel mixed-integer model for thermal unit commitment that incorporates power plant temperature variables, leading to more accurate start-up cost modeling and enhanced computational efficiency validated on real-world cases.

Contribution

It proposes a new temperature-based modeling approach for start-up costs in MIP unit commitment, reducing the integrality gap and improving solution speed.

Findings

Lower integrality gap compared to existing models

Significant computational efficiency improvements

Validated on real-world test cases with CPLEX

Abstract

This paper presents an improved mixed-integer model for the Thermal Unit Commitment Problem. By introducing new variables for the temperature of each thermal unit, the off-time-dependent start-up costs are modeled accurately and with a lower integrality gap than state-of-the-art formulations. This new approach significantly improves computational efficiency compared to existing formulations, even if they only model a rough approximation of the start-up costs. Our findings were validated on real-world test cases using CPLEX.