{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T18:54:49Z","timestamp":1777488889020,"version":"3.51.4"},"reference-count":41,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2020,8,6]],"date-time":"2020-08-06T00:00:00Z","timestamp":1596672000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["RTC-2017-6712-3"],"award-info":[{"award-number":["RTC-2017-6712-3"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007515","name":"Universidad de Valladolid","doi-asserted-by":"publisher","award":["2018 pre-doctoral research contract from the budget application 180113-541A.2.01e691"],"award-info":[{"award-number":["2018 pre-doctoral research contract from the budget application 180113-541A.2.01e691"]}],"id":[{"id":"10.13039\/501100007515","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Newly installed renewable power capacity has been increasing incredibly in recent years. For example, in 2018, 181 GW were installed worldwide. In this scenario, in which photovoltaic (PV) energy plays a leading role, it is essential for main players involved in PV plants to be able to identify the failure modes in PV modules in order to reduce investment risk, to focus their maintenance efforts on preventing those failures and to improve longevity and performance of PV plants. Among the different systems for defects detection, conventional infrared thermography (IRT) is the fastest and least expensive technique. It can be applied in illumination and in dark conditions, both indoor and outdoor. These two methods can provide complementary results for the same kind of defects, which is analyzed and characterized in this research. Novel investigation in PV systems propose the use of a power inverter with bidirectional power flow capability for PV plants maintenance, which extremely facilitates the electroluminescence (EL) inspections, as well as the outdoor IRT in the fourth quadrant.<\/jats:p>","DOI":"10.3390\/s20164395","type":"journal-article","created":{"date-parts":[[2020,8,6]],"date-time":"2020-08-06T09:41:21Z","timestamp":1596706881000},"page":"4395","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Infrared Thermography for the Detection and Characterization of Photovoltaic Defects: Comparison between Illumination and Dark Conditions"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2834-5591","authenticated-orcid":false,"given":"Sara","family":"Gallardo-Saavedra","sequence":"first","affiliation":[{"name":"Campus Universitario Duques de Soria, Universidad de Valladolid, 42004 Soria, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8822-2948","authenticated-orcid":false,"given":"Luis","family":"Hern\u00e1ndez-Callejo","sequence":"additional","affiliation":[{"name":"Campus Universitario Duques de Soria, Universidad de Valladolid, 42004 Soria, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4457-3551","authenticated-orcid":false,"given":"Mar\u00eda del Carmen","family":"Alonso-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Centro de Investigaciones Energ\u00e9ticas, Medioambientales y Tecnol\u00f3gicas (CIEMAT), Photovoltaic Solar Energy Unit, Energy Department, 28040, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5045-6311","authenticated-orcid":false,"given":"Jes\u00fas","family":"Mu\u00f1oz-Cruzado-Alba","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n CIRCE, Parque Empresarial Dinamiza, Avenida Ranillas Edificio 3D, 1\u00aa Planta, 50018 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5789-2156","authenticated-orcid":false,"given":"Javier","family":"Ballest\u00edn-Fuertes","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n CIRCE, Parque Empresarial Dinamiza, Avenida Ranillas Edificio 3D, 1\u00aa Planta, 50018 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,6]]},"reference":[{"key":"ref_1","unstructured":"REN21 (2019). 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