{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:17:00Z","timestamp":1760242620149,"version":"build-2065373602"},"reference-count":61,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,12,1]],"date-time":"2017-12-01T00:00:00Z","timestamp":1512086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>We consider a Unit Commitment Problem (UCP) addressing not only the economic objective of minimizing the total production costs\u2014as is done in the standard UCP\u2014but also addressing environmental concerns. Our approach utilizes a multi-objective formulation and includes in the objective function a criterion to minimize the emission of pollutants. Environmental concerns are having a significant impact on the operation of power systems related to the emissions from fossil-fuelled power plants. However, the standard UCP, which minimizes just the total production costs, is inadequate to address environmental concerns. We propose to address the UCP with environmental concerns as a multi-objective problem and use a metaheuristic approach combined with a non-dominated sorting procedure to solve it. The metaheuristic developed is a variant of an evolutionary algorithm, known as Biased Random Key Genetic Algorithm. Computational experiments have been carried out on benchmark problems with up to 100 generation units for a 24 h scheduling horizon. The performance of the method, as well as the quality, diversity and the distribution characteristics of the solutions obtained are analysed. It is shown that the method proposed compares favourably against alternative approaches in most cases analysed.<\/jats:p>","DOI":"10.3390\/en10122029","type":"journal-article","created":{"date-parts":[[2017,12,1]],"date-time":"2017-12-01T12:30:16Z","timestamp":1512131416000},"page":"2029","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["A Metaheuristic Approach to the Multi-Objective Unit Commitment Problem Combining Economic and Environmental Criteria"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5825-1732","authenticated-orcid":false,"given":"Lu\u00eds","family":"Roque","sequence":"first","affiliation":[{"name":"Departamento de Matem\u00e1tica, Instituto Superior de Engenharia do Porto, 4200-072 Porto, Portugal"},{"name":"LIAAD-INESC-TEC, Instituto de Engenharia de Sistemas e Computadores, Tecnologia e Ci\u00eancia, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9402-2088","authenticated-orcid":false,"given":"Dalila","family":"Fontes","sequence":"additional","affiliation":[{"name":"LIAAD-INESC-TEC, Instituto de Engenharia de Sistemas e Computadores, Tecnologia e Ci\u00eancia, 4200-465 Porto, Portugal"},{"name":"Faculdade de Economia, Universidade do Porto, 4200-464 Porto, Portugal"}]},{"given":"Fernando","family":"Fontes","sequence":"additional","affiliation":[{"name":"SYSTEC-ISR-Porto, Faculdade de Engenharia, Universidade do Porto, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2017,12,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rebennack, S., Pardalos, P.M., Pereira, M.V., and Iliadis, N. 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