{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:47:49Z","timestamp":1760143669549,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,2,20]],"date-time":"2024-02-20T00:00:00Z","timestamp":1708387200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"national funds through FCT\/MCTES (PIDDAC)","award":["LEPABE, UIDB\/00511\/2020","ALiCE, LA\/P\/0045\/2020","CIETI UIDB\/04730\/2020","UIDP\/04730\/2020","INESC TEC, LA\/P\/0063\/2020"],"award-info":[{"award-number":["LEPABE, UIDB\/00511\/2020","ALiCE, LA\/P\/0045\/2020","CIETI UIDB\/04730\/2020","UIDP\/04730\/2020","INESC TEC, LA\/P\/0063\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>Energy and materials are increasingly important in industrialized countries, and they impact the economy, sustainability, and people\u2019s future. The purpose of this work was to study the relationship between energy and the circular economy using methods such as Pearson\u2019s correlation and a principal component analysis. Thus, 12 strong correlations were found, with 5 of them between the following relevant variables from two different subjects: the correlations of the raw material consumption, the domestic material consumption, and the material import dependency with the final energy consumption in transport (0.81, 0.92, and 0.81); the correlation of the circular material use rate with the final energy consumption in households (0.70); and the correlation of the material import dependency with the final energy consumption in industry (0.89). The time series forecast was only conclusive for the waste generated, showing that it will increase in the next 10 years.<\/jats:p>","DOI":"10.3390\/su16051728","type":"journal-article","created":{"date-parts":[[2024,2,20]],"date-time":"2024-02-20T04:36:22Z","timestamp":1708403782000},"page":"1728","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Energy and Circular Economy: Nexus beyond Concepts"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8866-1799","authenticated-orcid":false,"given":"Florinda F.","family":"Martins","sequence":"first","affiliation":[{"name":"Instituto Superior de Engenharia do Porto\u2014ISEP, Rua Dr. Ant\u00f3nio Bernardino de Almeida, 431, 4249-015 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5712-9954","authenticated-orcid":false,"given":"H\u00e9lio","family":"Castro","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia do Porto\u2014ISEP, Rua Dr. Ant\u00f3nio Bernardino de Almeida, 431, 4249-015 Porto, Portugal"},{"name":"Institute for Systems and Computer Engineering, Technology and Science\u2014INESC TEC, Rua Dr. Roberto Frias s\/n, 4200-465 Porto, Portugal"}]},{"given":"Miroslava","family":"Smitkov\u00e1","sequence":"additional","affiliation":[{"name":"Institute of Power and Applied Electrical Engineering, FEI\u2014Slovak University of Technology, Ilkovi\u010dova 3, 841 04 Bratislava, Slovakia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4202-5551","authenticated-orcid":false,"given":"Carlos","family":"Felgueiras","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia do Porto\u2014ISEP, Rua Dr. Ant\u00f3nio Bernardino de Almeida, 431, 4249-015 Porto, Portugal"},{"name":"CIETI\u2014Center for Innovation in Engineering and Industrial Technology, School of Engineering (ISEP), Polytechnic of Porto (P.Porto), Rua Dr. Ant\u00f3nio Bernardino de Almeida 431, 4249-015 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2185-6401","authenticated-orcid":false,"given":"N\u00eddia","family":"Caetano","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia do Porto\u2014ISEP, Rua Dr. Ant\u00f3nio Bernardino de Almeida, 431, 4249-015 Porto, Portugal"},{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"ALiCE\u2014Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"R535","DOI":"10.1016\/j.cub.2008.06.036","article-title":"The population bomb","volume":"18","author":"Williams","year":"2008","journal-title":"Curr. 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