Radiative cooling performance of a modified paint formulation with an integrated UV and convection shielding layer

Radiative cooling performance of a modified paint formulation with an integrated UV and convection shielding layer | 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 Radiative cooling performance of a modified paint formulation with an integrated UV and convection shielding layer Giuseppe Emanuele Lio, Sara Levorin, Atakan Erdogan, Jeremy Werlé, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4749222/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 28 Oct, 2024 Read the published version in International Journal of Thermophysics → Version 1 posted 9 You are reading this latest preprint version Abstract Passive radiative cooling (PRC) technology promises to reduce a significant fraction of our energy needs and carbon footprint associated with cooling. Among different approaches, paint-like systems present several advantages in cost-effectiveness, scalability, and application ease. We report on a PRC system consisting of a paint mixture modified with 50 %wt glass bubbles and a top polypropylene-polyethylene-polypropylene (PP-PE-PP) film typically used as a battery separator. The resulting material exhibits a solar reflectance of 94 % and an absorption (evaluated by Attenuated Total Reflectance spectroscopy) with a peak at 10 µm of 60 %. The addition of the glass bubbles and the top film increases the paint reflectance over the solar spectrum and the UV, thanks to the nanoporous PP-PE-PP film (NPF), while allowing most thermal radiation through, shielding from convection, and making the coating more easily washable. The material has been tested under realistic outdoor conditions, checking the different performance obtained when sticking the PP-PE-PP film directly onto the wet paint layer or by using it as a separate windshield enclosing the sample test chamber. Despite its high solar reflectance, no radiative cooling is observed with respect to ambient temperature during the peak hours (solar irradiation >500 W m −2). Below this threshold, a temperature drop of −3 °C and a cooling power exceeding 100 W m−2 is observed. Notably, even using a visibly opaque convection shield, the configuration where the PP-PE-PP film seals the sample results in a substantial overheating of the air pocket surrounding the sample , which is detrimental to obtaining a temperature drop with respect to the true ambient temperature. Passive Radiative Cooling Solar reflectance Infrared emissivity Temperature drop Cooling power Windshield Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 28 Oct, 2024 Read the published version in International Journal of Thermophysics → Version 1 posted Editorial decision: Revision requested 29 Jul, 2024 Reviews received at journal 26 Jul, 2024 Reviewers agreed at journal 22 Jul, 2024 Reviews received at journal 18 Jul, 2024 Reviewers agreed at journal 17 Jul, 2024 Reviewers invited by journal 17 Jul, 2024 Editor assigned by journal 17 Jul, 2024 Submission checks completed at journal 17 Jul, 2024 First submitted to journal 16 Jul, 2024 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. 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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-4749222","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":333037076,"identity":"c62691d2-362f-45a7-b159-ae37c896f137","order_by":0,"name":"Giuseppe Emanuele Lio","email":"data:image/png;base64,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","orcid":"","institution":"University of Florence","correspondingAuthor":true,"prefix":"","firstName":"Giuseppe","middleName":"Emanuele","lastName":"Lio","suffix":""},{"id":333037079,"identity":"042db1b4-24e1-4cc4-a4eb-120e0a7194e1","order_by":1,"name":"Sara Levorin","email":"","orcid":"","institution":"Università di Padova","correspondingAuthor":false,"prefix":"","firstName":"Sara","middleName":"","lastName":"Levorin","suffix":""},{"id":333037080,"identity":"6628849f-97fc-4672-b55e-93664d518603","order_by":2,"name":"Atakan Erdogan","email":"","orcid":"","institution":"Università di Padova","correspondingAuthor":false,"prefix":"","firstName":"Atakan","middleName":"","lastName":"Erdogan","suffix":""},{"id":333037081,"identity":"f978271a-b9bc-42e0-8d87-1fa92f379305","order_by":3,"name":"Jeremy Werlé","email":"","orcid":"","institution":"European Laboratory for Non-Linear Spectroscopy","correspondingAuthor":false,"prefix":"","firstName":"Jeremy","middleName":"","lastName":"Werlé","suffix":""},{"id":333037084,"identity":"1e608bd1-87fd-4fe0-9cbc-484cb6b1e2ec","order_by":4,"name":"Alain J. 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