Recycling Aluminium Beverage Cans for Renewable Heating: Design and Evaluation of a Double-Pass Beverage Can Solar Air Heater for Greenhouse Applications

Recycling Aluminium Beverage Cans for Renewable Heating: Design and Evaluation of a Double-Pass Beverage Can Solar Air Heater for Greenhouse Applications | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Recycling Aluminium Beverage Cans for Renewable Heating: Design and Evaluation of a Double-Pass Beverage Can Solar Air Heater for Greenhouse Applications Sishosonke Caspar Nsele, Alaika Kassim, Sipho Sibanda, Tilahun Seyoum Workneh This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9044704/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study evaluated the performance of a low-cost, double-pass beverage can solar air heater (BCSAH) constructed from recycled aluminium beverage cans for potential greenhouse heating, supporting United Nations Sustainable Development Goal 7 (Affordable and Clean Energy). The BCSAH was built with plywood, polystyrene insulation, and a plexiglass cover, incorporating 192 recycled 500 ml cans as the absorber plate. Tests were conducted in Pietermaritzburg, South Africa, under winter conditions at three tilt angles (26°, 31°, 36°) based on photovoltaic winter recommended tilt angles. Key parameters measured included outlet temperature, solar irradiance, thermal efficiency, and heat distribution, using 14 K-type thermocouples, a pyranometer, and an anemometer at a constant air mass flow rate of 0.02 kg·s⁻¹. The system achieved significant temperature gains, with second-pass air reaching 128.8°C and maximum outlet temperatures of 94.36 ± 1.35°C. Although tilt angle did not yield statistically significant temperature differences, thermal efficiency increased from 63.36 ± 9.06% for 26° to 67.31 ± 11.78% for 36°. The results highlight the potential of recycled BCSAH to reduce fossil fuel use in greenhouses and other agricultural applications such as soil sterilisation, juice/milk pasteurisation, and pest control. The unit was cost-effective (R 3,470), aligning with circular economy principles and renewable energy goals. Design improvements are suggested, including thinner insulation such as phenolic foam, internal baffles for airflow optimisation, and solar panel integration for off-grid monitoring. Future research should explore multiple units, conduct a broader airflow analysis, and conduct testing across different regions. Integration with heat storage is also recommended. solar air heaters discarded aluminium soda cans temperature difference instantaneous efficiency double pass Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9044704","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":602286257,"identity":"e3ab3b54-8d83-476e-96c0-3eafa94762c7","order_by":0,"name":"Sishosonke Caspar Nsele","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6UlEQVRIiWNgGAWjYBAC+QYGZjCDj4H5GJjBxk5Ai8EBqBY2BrY0BoYEIIOZkBYGuBYeM7AWBoJa2HsPG3zcUSfHxt7z7cHHH9vk+ZgZGD98zMHjl55zyYkzzxw2ZuM5u91wRsJtwzZmBmbJmdvwWHMjx/gwb9uBxDaJ3G3SPAm3GYFa2Jh5CWn521ZX3yb/5hlIiz1RWpKBJiewSfCwgbQkEtRicOaMsWFv22HDNp40M8kZabeT25gZm/H6Rb69x1jiZ1udPD/74WcSH2xu285vbz744SM+h2EBjA2kqR8Fo2AUjIJRgAEASM1KDYZ0BMYAAAAASUVORK5CYII=","orcid":"","institution":"University of KwaZulu-Natal","correspondingAuthor":true,"prefix":"","firstName":"Sishosonke","middleName":"Caspar","lastName":"Nsele","suffix":""},{"id":602286258,"identity":"ec66450d-b09e-47af-87b0-a9fbbbe8163e","order_by":1,"name":"Alaika Kassim","email":"","orcid":"","institution":"University of KwaZulu-Natal","correspondingAuthor":false,"prefix":"","firstName":"Alaika","middleName":"","lastName":"Kassim","suffix":""},{"id":602286260,"identity":"a218f842-cffd-4b94-b7f6-0c9165b86f47","order_by":2,"name":"Sipho Sibanda","email":"","orcid":"","institution":"Agricultural Research Council of South Africa","correspondingAuthor":false,"prefix":"","firstName":"Sipho","middleName":"","lastName":"Sibanda","suffix":""},{"id":602286261,"identity":"c496dc04-8dba-4f30-95db-4cf6cae5bbf7","order_by":3,"name":"Tilahun Seyoum Workneh","email":"","orcid":"","institution":"University of KwaZulu-Natal","correspondingAuthor":false,"prefix":"","firstName":"Tilahun","middleName":"Seyoum","lastName":"Workneh","suffix":""}],"badges":[],"createdAt":"2026-03-06 00:38:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9044704/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9044704/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105752171,"identity":"68eb824b-2585-4fa0-be0b-2f99fc044e33","added_by":"auto","created_at":"2026-03-30 15:55:24","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1593693,"visible":true,"origin":"","legend":"","description":"","filename":"ManuscriptHeatandMassTransfer.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9044704/v1_covered_b4730730-c09c-48d9-810f-bf8a44a96c87.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Recycling Aluminium Beverage Cans for Renewable Heating: Design and Evaluation of a Double-Pass Beverage Can Solar Air Heater for Greenhouse Applications","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"solar air heaters, discarded aluminium soda cans, temperature difference, instantaneous efficiency, double pass","lastPublishedDoi":"10.21203/rs.3.rs-9044704/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9044704/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study evaluated the performance of a low-cost, double-pass beverage can solar air heater (BCSAH) constructed from recycled aluminium beverage cans for potential greenhouse heating, supporting United Nations Sustainable Development Goal 7 (Affordable and Clean Energy). The BCSAH was built with plywood, polystyrene insulation, and a plexiglass cover, incorporating 192 recycled 500 ml cans as the absorber plate. Tests were conducted in Pietermaritzburg, South Africa, under winter conditions at three tilt angles (26°, 31°, 36°) based on photovoltaic winter recommended tilt angles. Key parameters measured included outlet temperature, solar irradiance, thermal efficiency, and heat distribution, using 14 K-type thermocouples, a pyranometer, and an anemometer at a constant air mass flow rate of 0.02 kg·s⁻¹. The system achieved significant temperature gains, with second-pass air reaching 128.8°C and maximum outlet temperatures of 94.36 ± 1.35°C. Although tilt angle did not yield statistically significant temperature differences, thermal efficiency increased from 63.36 ± 9.06% for 26° to 67.31 ± 11.78% for 36°. The results highlight the potential of recycled BCSAH to reduce fossil fuel use in greenhouses and other agricultural applications such as soil sterilisation, juice/milk pasteurisation, and pest control. The unit was cost-effective (R 3,470), aligning with circular economy principles and renewable energy goals. Design improvements are suggested, including thinner insulation such as phenolic foam, internal baffles for airflow optimisation, and solar panel integration for off-grid monitoring. Future research should explore multiple units, conduct a broader airflow analysis, and conduct testing across different regions. Integration with heat storage is also recommended.\u003c/p\u003e","manuscriptTitle":"Recycling Aluminium Beverage Cans for Renewable Heating: Design and Evaluation of a Double-Pass Beverage Can Solar Air Heater for Greenhouse Applications","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-09 04:54:40","doi":"10.21203/rs.3.rs-9044704/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9b40844a-2258-445d-bbaa-bd8421068528","owner":[],"postedDate":"March 9th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-05-03T15:25:15+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-09 04:54:40","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9044704","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9044704","identity":"rs-9044704","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}