{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T17:45:49Z","timestamp":1777657549897,"version":"3.51.4"},"reference-count":36,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,5,10]],"date-time":"2021-05-10T00:00:00Z","timestamp":1620604800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ag\u00eancia Nacional de Energia El\u00e9trica (ANEEL) and Equatorial Energia","award":["PD02\/2016"],"award-info":[{"award-number":["PD02\/2016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Monitoring and data acquisition are essential to recognize the renewable resources available on-site, evaluate electrical conversion efficiency, detect failures, and optimize electrical production. Commercial monitoring systems for the photovoltaic system are generally expensive and closed for modifications. This work proposes a low-cost real-time internet of things system for micro and mini photovoltaic generation systems that can monitor continuous voltage, continuous current, alternating power, and seven meteorological variables. The proposed system measures all relevant meteorological variables and directly acquires photovoltaic generation data from the plant (not from the inverter). The system is implemented using open software, connects to the internet without cables, stores data locally and in the cloud, and uses the network time protocol to synchronize the devices\u2019 clocks. To the best of our knowledge, no work reported in the literature presents these features altogether. Furthermore, experiments carried out with the proposed system showed good effectiveness and reliability. This system enables fog and cloud computing in a photovoltaic system, creating a time series measurements data set, enabling the future use of machine learning to create smart photovoltaic systems.<\/jats:p>","DOI":"10.3390\/s21093293","type":"journal-article","created":{"date-parts":[[2021,5,10]],"date-time":"2021-05-10T10:49:51Z","timestamp":1620643791000},"page":"3293","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":61,"title":["A Low-Cost IoT System for Real-Time Monitoring of Climatic Variables and Photovoltaic Generation for Smart Grid Application"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4111-8721","authenticated-orcid":false,"given":"Gustavo Costa Gomes de","family":"Melo","sequence":"first","affiliation":[{"name":"Computing Institute, A. C. Sim\u00f5es Campus, Federal University of Alagoas\u2014UFAL, Macei\u00f3, AL 57072-970, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0643-737X","authenticated-orcid":false,"given":"Igor Cavalcante","family":"Torres","sequence":"additional","affiliation":[{"name":"Center of Agrarian Sciences, Engineering and Agricultural Sciences Campus, Federal University of Alagoas\u2014UFAL, Rio Largo, AL 57100-000, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6769-4946","authenticated-orcid":false,"given":"\u00cdcaro Bezzera Queiroz de","family":"Ara\u00fajo","sequence":"additional","affiliation":[{"name":"Computing Institute, A. C. Sim\u00f5es Campus, Federal University of Alagoas\u2014UFAL, Macei\u00f3, AL 57072-970, Brazil"}]},{"given":"Davi Bibiano","family":"Brito","sequence":"additional","affiliation":[{"name":"Computing Institute, A. C. Sim\u00f5es Campus, Federal University of Alagoas\u2014UFAL, Macei\u00f3, AL 57072-970, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0558-9120","authenticated-orcid":false,"given":"Erick de Andrade","family":"Barboza","sequence":"additional","affiliation":[{"name":"Computing Institute, A. C. Sim\u00f5es Campus, Federal University of Alagoas\u2014UFAL, Macei\u00f3, AL 57072-970, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,10]]},"reference":[{"key":"ref_1","unstructured":"(2021, May 05). Renewables 2020 Global Status Report. Available online: https:\/\/www.ren21.net\/reports\/global-status-report\/."},{"key":"ref_2","unstructured":"(2021, January 14). Infogr\u00e1fico ABSOLAR. Available online: http:\/\/www.absolar.org.br\/infografico-absolar.html."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Begovic, M.M., Kim, I., Novosel, D., Aguero, J.R., and Rohatgi, A. (2012, January 4\u20137). 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