{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T13:28:04Z","timestamp":1769606884065,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,4,7]],"date-time":"2025-04-07T00:00:00Z","timestamp":1743984000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FEDER Funds","award":["QREN-POFC-COMPETE-23101"],"award-info":[{"award-number":["QREN-POFC-COMPETE-23101"]}]},{"name":"FEDER Funds","award":["02\/C05-i01\/2022"],"award-info":[{"award-number":["02\/C05-i01\/2022"]}]},{"name":"FEDER Funds","award":["7253"],"award-info":[{"award-number":["7253"]}]},{"name":"Next Generation EU Funds","award":["QREN-POFC-COMPETE-23101"],"award-info":[{"award-number":["QREN-POFC-COMPETE-23101"]}]},{"name":"Next Generation EU Funds","award":["02\/C05-i01\/2022"],"award-info":[{"award-number":["02\/C05-i01\/2022"]}]},{"name":"Next Generation EU Funds","award":["7253"],"award-info":[{"award-number":["7253"]}]},{"name":"AM2R project \u201cMobilizing Agenda for business innovation in the Two Wheels sector\u201d","award":["QREN-POFC-COMPETE-23101"],"award-info":[{"award-number":["QREN-POFC-COMPETE-23101"]}]},{"name":"AM2R project \u201cMobilizing Agenda for business innovation in the Two Wheels sector\u201d","award":["02\/C05-i01\/2022"],"award-info":[{"award-number":["02\/C05-i01\/2022"]}]},{"name":"AM2R project \u201cMobilizing Agenda for business innovation in the Two Wheels sector\u201d","award":["7253"],"award-info":[{"award-number":["7253"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Processes"],"abstract":"<jats:p>This study presents an experimental and numerical investigation into the performance and control optimization of an Organic Rankine Cycle (ORC)-based micro-combined heat and power (micro-CHP) system. A steady-state, off-design, charge-sensitive model is developed to design a control strategy for an ORC micro-CHP combi-boiler, aiming to efficiently meet real-time domestic hot water demands (up to 40 \u00b0C and 35 kW) while generating up to 2 kW of electricity. The system utilizes a natural gas burner to evaporate the working fluid (R245fa), with combustion heat power, volumetric pump speed, and expander speed as control variables. Experimental and numerical evaluations generate steady-state control maps to identify optimal operating regions. A PID-based dynamic control strategy is then developed to stabilize operation during start-ups and user demand variations. The results confirm that the strategy delivers hot water within 1.5 min in simple boiler mode and 3 min in cogeneration mode while improving electricity generation stability and outperforming manual control. The findings demonstrate that integrating steady-state modeling with optimized control enhances the performance, responsiveness, and efficiency of ORC-based micro-CHP systems, making them a viable alternative for residential energy solutions.<\/jats:p>","DOI":"10.3390\/pr13041104","type":"journal-article","created":{"date-parts":[[2025,4,7]],"date-time":"2025-04-07T10:32:45Z","timestamp":1744021965000},"page":"1104","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Optimization of ORC-Based Micro-CHP Systems: An Experimental and Control-Oriented Study"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9411-0304","authenticated-orcid":false,"given":"M\u00e1rcio","family":"Santos","sequence":"first","affiliation":[{"name":"ADAI, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, P\u00f3lo II, 3030-788 Coimbra, Portugal"}]},{"given":"Jorge","family":"Andr\u00e9","sequence":"additional","affiliation":[{"name":"ADAI, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, P\u00f3lo II, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3575-9733","authenticated-orcid":false,"given":"Ricardo","family":"Mendes","sequence":"additional","affiliation":[{"name":"ADAI, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, P\u00f3lo II, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9908-7147","authenticated-orcid":false,"given":"Jos\u00e9 B.","family":"Ribeiro","sequence":"additional","affiliation":[{"name":"ADAI, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, P\u00f3lo II, 3030-788 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1016\/j.apenergy.2011.11.023","article-title":"Guidelines for Residential Micro-CHP Systems Design","volume":"97","author":"Bianchi","year":"2012","journal-title":"Appl. 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