Solving Large-Scale Unit Commitment Problems

Abstract:
Small and medium sized generation units are usually pooled in virtual power plants for an efficient management and access to energy markets. As the number of small and medium sized generation units in our power grids is growing, the associated unit commitment problem solved by virtual power plant operators is growing importantly. This work focuses on the efficient solution of large-scale unit commitment problems, aimed to be used for virtual power plants. The work is based on a standard unit commitment problem description and does not consider grid constraints. The paper presents the basic mathematical MILP formulation, some approaches to improve its performance by speed-up factors of 4-38, and results from a heuristic approach that could additionally improve the solution times by a factor of up to 500. A comparison on the quality and performance is done, followed by an analysis of pros and cons of the selected methodologies.