{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T22:24:08Z","timestamp":1792880648640,"version":"4.5.0"},"reference-count":51,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2019,3,21]],"date-time":"2019-03-21T00:00:00Z","timestamp":1553126400000},"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>One of the major challenges faced in the optimization process of existing heating systems is the harnessing and integration of a higher share of renewable energy. Centralized integration at the thermic source leads to high investment costs at the first investment stage, and low values of conversion, transport, and storage efficiencies, due to high levels of heat loss from large-capacity entropic systems. This research paper presents a case study on the partially decentralized integration of thermal solar fields that are used for heat production in crowded urban areas within the optimization process of the existing heating system in the city of Oradea, Romania. A deterministic method was used as the method for the calculation of heat demand, in both stationary\u2014hourly heat demand and dynamic regimes\u2014annual heat demand, and the simulations within the configuration and the optimization process of the hybrid heating systems were carried out. In the case study, four representative urban areas with different thermal densities were analyzed within two working scenarios, which took into account the energy performances of the buildings inside the studied areas before thermal retrofitting, and after a usual thermal retrofit.<\/jats:p>","DOI":"10.3390\/en12061088","type":"journal-article","created":{"date-parts":[[2019,3,21]],"date-time":"2019-03-21T12:28:01Z","timestamp":1553171281000},"page":"1088","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Assessing the Energy Performance of Solar Thermal Energy for Heat Production in Urban Areas: A Case Study"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5929-1071","authenticated-orcid":false,"given":"Teodora Melania","family":"\u0218oimo\u0219an","sequence":"first","affiliation":[{"name":"Faculty of Civil Engineering, Technical University of Cluj-Napoca, Constantin Daicoviciu Street, No. 15, 400020 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ligia Mihaela","family":"Moga","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering, Technical University of Cluj-Napoca, Constantin Daicoviciu Street, No. 15, 400020 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gelu","family":"Danku","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering, Technical University of Cluj-Napoca, Constantin Daicoviciu Street, No. 15, 400020 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aurica","family":"C\u0103zil\u0103","sequence":"additional","affiliation":[{"name":"Faculty of Mechanics, Technical University of Cluj-Napoca, Cluj-Napoca, Boulevard of Muncii, No. 103-105, 400641 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniela Lucia","family":"Manea","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering, Technical University of Cluj-Napoca, Constantin Daicoviciu Street, No. 15, 400020 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,21]]},"reference":[{"key":"ref_1","unstructured":"European Technology Platform on Renewable Heating and Cooling (2011). 2020\u20132030\u20132050 Common Vision for the Renewable Heating & Cooling Sector in Europe, Publications Office of the European Union."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3390\/en11040890","article-title":"Review on the Evolution and Application of the Thermal Network Method for Energy Assessments in Buildings","volume":"11","author":"Bagheri","year":"2018","journal-title":"Energies"},{"key":"ref_3","unstructured":"European Commision CE (2016). 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