Global InformationPassive daytime radiative cooling information
Passive daytime radiative cooling (PDRC) is a zero-energy building cooling method proposed as a solution to reduce air conditioning, lower urban heat island effect, cool human body temperatures in extreme heat, move toward carbon neutrality and control global warming by enhancing terrestrial heat flow to outer space through the installation of thermally-emissive surfaces on Earth that require zero energy consumption or pollution.[2][3][4][5][6][1][7][8][9] In contrast to compression-based cooling systems that are prevalently used (e.g., air conditioners), consume substantial amounts of energy, have a net heating effect, require ready access to electricity and often require coolants that are ozone-depleting or have a strong greenhouse effect,[10][11] application of PDRCs may also increase the efficiency of systems benefiting from a better cooling, such like photovoltaic systems, dew collection techniques, and thermoelectric generators.[12][13]
PDRC surfaces are designed to be high in solar reflectance (to minimize heat gain) and strong in longwave infrared (LWIR) thermal radiation heat transfer through the atmosphere's infrared window (8–13 µm) to cool temperatures even during the daytime.[14][15][16] It is also referred to as passive radiative cooling, daytime passive radiative cooling, radiative sky cooling, photonic radiative cooling, and terrestrial radiative cooling.[15][16][12][17] PDRC differs from solar radiation management because it increases radiative heat emission rather than merely reflecting the absorption of solar radiation.[18]
Some estimates propose that if 1–2% of the Earth's surface area were dedicated to PDRC that warming would cease and temperature increases would be rebalanced to survivable levels.[19][16] Regional variations provide different cooling potentials with desert and temperate climates benefiting more from application than tropical climates, attributed to the effects of humidity and cloud cover on reducing the effectiveness of PDRCs.[20][21][22] Low-cost scalable PDRC materials feasible for mass production have been developed, such as coatings, thin films, metafabrics, aerogels, and biodegradable surfaces.
PDRCs can be included in self-adaptive systems, 'switching' from passive cooling to heating to mitigate any potential "overcooling" effects in urban environments.[3][23] They have also been developed in colors other than white, although there is generally a tradeoff in cooling potential, since darker color surfaces are less reflective.[24][25] Research, development, and interest in PDRCs has grown rapidly since the 2010s, which has been attributed to a scientific breakthrough in the use of photonic metamaterials to achieve daytime cooling in 2014,[26][12][27] along with growing concerns over energy use and global warming.[28][29]
Passive daytime radiative cooling (PDRC) uses the coldness of outer space as a renewable energy source to achieve daytime cooling that can be used in many applications,[30][31][32] such as indoor space cooling,[33][34] outdoor urban heat island mitigation,[35][36] and solar cell efficiency.[37][38] PDRC surfaces are designed to be high in solar reflectance to minimize heat gain and strong in longwave infrared (LWIR) thermal radiation heat transfer.[39] On a planetary scale, it has been proposed as a way to slow and reverse global warming.[40][41] PDRC applications are deployed as sky-facing surfaces, similar to other renewable energy sources such as photovoltaic systems and solar thermal collectors.[38] PDRC became possible with the ability to suppress solar heating using photonic metamaterials, first published in a study by Raman et al. to the scientific community in 2014.[37][42] PDRC applications for indoor space cooling is growing with an estimated "market size of ~$27 billion in 2025."[43]
- ^ a b Chen, Meijie; Pang, Dan; Chen, Xingyu; Yan, Hongjie; Yang, Yuan (2022). "Passive daytime radiative cooling: Fundamentals, material designs, and applications". EcoMat. 4. doi:10.1002/eom2.12153. S2CID 240331557.
Passive daytime radiative cooling (PDRC) dissipates terrestrial heat to the extremely cold outer space without using any energy input or producing pollution. It has the potential to simultaneously alleviate the two major problems of energy crisis and global warming.
- ^ Bijarniya, Jay Prakash; Sarkar, Jahar; Maiti, Pralay (November 2020). "Review on passive daytime radiative cooling: Fundamentals, recent researches, challenges and opportunities". Renewable and Sustainable Energy Reviews. 133: 110263. doi:10.1016/j.rser.2020.110263. S2CID 224874019 – via Elsevier Science Direct.
- ^ a b Chen, Meijie; Pang, Dan; Chen, Xingyu; Yan, Hongjie; Yang, Yuan (2022). "Passive daytime radiative cooling: Fundamentals, material designs, and applications". EcoMat. 4. doi:10.1002/eom2.12153. S2CID 240331557.
- ^ Cite error: The named reference
:12was invoked but never defined (see the help page). - ^ Cite error: The named reference
:13was invoked but never defined (see the help page). - ^ Liang, Jun; Wu, Jiawei; Guo, Jun; Li, Huagen; Zhou, Xianjun; Liang, Sheng; Qiu, Cheng-Wei; Tao, Guangming (September 2022). "Radiative cooling for passive thermal management towards sustainable carbon neutrality". National Science Review. 10 (1): nwac208. doi:10.1093/nsr/nwac208. PMC 9843130. PMID 36684522.
- ^ Munday, Jeremy (2019). "Tackling Climate Change through Radiative Cooling". Joule. 3 (9): 2057–2060. doi:10.1016/j.joule.2019.07.010. S2CID 201590290.
By covering the Earth with a small fraction of thermally emitting materials, the heat flow away from the Earth can be increased, and the net radiative flux can be reduced to zero (or even made negative), thus stabilizing (or cooling) the Earth.
- ^ Yin, Xiaobo; Yang, Ronggui; Tan, Gang; Fan, Shanhui (November 2020). "Terrestrial radiative cooling: Using the cold universe as a renewable and sustainable energy source". Science. 370 (6518): 786–791. Bibcode:2020Sci...370..786Y. doi:10.1126/science.abb0971. PMID 33184205. S2CID 226308213.
...terrestrial radiative cooling has emerged as a promising solution for mitigating urban heat islands and for potentially fighting against global warming if it can be implemented at a large scale.
- ^ Bijarniya, Jay Prakash; Sarkar, Jahar; Maiti, Pralay (November 2020). "Review on passive daytime radiative cooling: Fundamentals, recent researches, challenges and opportunities". Renewable and Sustainable Energy Reviews. 133: 110263. doi:10.1016/j.rser.2020.110263. S2CID 224874019 – via Elsevier Science Direct.
Passive radiative cooling can be considered as a renewable energy source, which can pump heat to cold space and make the devices more efficient than ejecting heat at earth atmospheric temperature.
- ^ Chen, Guoliang; Wang, Yaming; Qiu, Jun; Cao, Jianyun; Zou, Yongchun; Wang, Shuqi; Jia, Dechang; Zhou, Yu (August 2021). "A facile bioinspired strategy for accelerating water collection enabled by passive radiative cooling and wettability engineering". Materials & Design. 206: 109829. doi:10.1016/j.matdes.2021.109829. S2CID 236255835.
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:26was invoked but never defined (see the help page). - ^ a b c Heo, Se-Yeon; Ju Lee, Gil; Song, Young Min (June 2022). "Heat-shedding with photonic structures: radiative cooling and its potential". Journal of Materials Chemistry C. 10 (27): 9915–9937. doi:10.1039/D2TC00318J. S2CID 249695930 – via Royal Society of Chemistry.
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:34was invoked but never defined (see the help page). - ^ "What is 3M Passive Radiative Cooling?". 3M. Archived from the original on 22 September 2021. Retrieved 27 September 2022.
Passive Radiative Cooling is a natural phenomenon that only occurs at night in nature because all nature materials absorb more solar energy during the day than they are able to radiate to the sky.
- ^ a b Wang, Tong; Wu, Yi; Shi, Lan; Hu, Xinhua; Chen, Min; Wu, Limin (2021). "A structural polymer for highly efficient all-day passive radiative cooling". Nature Communications. 12 (365): 365. doi:10.1038/s41467-020-20646-7. PMC 7809060. PMID 33446648.
Accordingly, designing and fabricating efficient PDRC with sufficiently high solar reflectance (𝜌¯solar) (λ ~ 0.3–2.5 μm) to minimize solar heat gain and simultaneously strong LWIR thermal emittance (ε¯LWIR) to maximize radiative heat loss is highly desirable. When the incoming radiative heat from the Sun is balanced by the outgoing radiative heat emission, the temperature of the Earth can reach its steady state.
- ^ a b c Zevenhovena, Ron; Fält, Martin (June 2018). "Radiative cooling through the atmospheric window: A third, less intrusive geoengineering approach". Energy. 152: 27. Bibcode:2018Ene...152...27Z. doi:10.1016/j.energy.2018.03.084. S2CID 116318678 – via Elsevier Science Direct.
An alternative, third geoengineering approach would be enhanced cooling by thermal radiation from the Earth's surface into space." [...] "With 100 W/m2 as a demonstrated passive cooling effect, a surface coverage of 0.3% would then be needed, or 1% of Earth's land mass surface. If half of it would be installed in urban, built areas which cover roughly 3% of the Earth's land mass, a 17% coverage would be needed there, with the remainder being installed in rural areas.
- ^ Cite error: The named reference
:21was invoked but never defined (see the help page). - ^ Cite error: The named reference
Mundaywas invoked but never defined (see the help page). - ^ Munday, Jeremy (2019). "Tackling Climate Change through Radiative Cooling". Joule. 3 (9): 2057–2060. doi:10.1016/j.joule.2019.07.010. S2CID 201590290.
If only 1%–2% of the Earth's surface were instead made to radiate at this rate rather than its current average value, the total heat fluxes into and away from the entire Earth would be balanced and warming would cease.
- ^ Han, Di; Fei, Jipeng; Li, Hong; Ng, Bing Feng (August 2022). "The criteria to achieving sub-ambient radiative cooling and its limits in tropical daytime". Building and Environment. 221 (1): 109281. Bibcode:2022BuEnv.22109281H. doi:10.1016/j.buildenv.2022.109281 – via Elsevier Science Direct.
- ^ Huang, Jingyuan; Lin, Chongjia; Li, Yang; Huang, Baoling (May 2022). "Effects of humidity, aerosol, and cloud on subambient radiative cooling". International Journal of Heat and Mass Transfer. 186: 122438. doi:10.1016/j.ijheatmasstransfer.2021.122438. S2CID 245805048 – via Elsevier Science Direct.
- ^ Liu, Junwei; Zhang, Ji; Zhang, Debao; Jiao, Shifei; Xing, Jingcheng; Tang, Huajie; Zhang, Ying; Li, Shuai; Zhou, Zhihua; Zuo, Jian (September 2020). "Sub-ambient radiative cooling with wind cover". Renewable and Sustainable Energy Reviews. 130: 109935. doi:10.1016/j.rser.2020.109935. S2CID 219911962 – via Elsevier Science Direct.
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:14was invoked but never defined (see the help page). - ^ Cite error: The named reference
:16was invoked but never defined (see the help page). - ^ Cite error: The named reference
:38was invoked but never defined (see the help page). - ^ Cite error: The named reference
Ramanwas invoked but never defined (see the help page). - ^ Cite error: The named reference
Banikwas invoked but never defined (see the help page). - ^ Park, Chanil; Park, Choyeon; Nie, Xiao; Lee, Jaeho; Kim, Yong Seok; Yoo, Youngjae (2022). "Fully Organic and Flexible Biodegradable Emitter for Global Energy-Free Cooling Applications". ACS Sustainable Chemistry & Engineering. 10 (21): 7091–7099. doi:10.1021/acssuschemeng.2c01182 – via ACS Publications.
- ^ Miranda, Nicole D.; Renaldi, Renaldi; Khosla, Radhika; McCulloch, Malcolm D. (October 2021). "Bibliometric analysis and landscape of actors in passive cooling research". Renewable and Sustainable Energy Reviews. 149: 111406. doi:10.1016/j.rser.2021.111406 – via Elsevier Science Direct.
In the last three years, however, publications on radiative cooling and solar control have been the most numerous and hence are promising technologies in the field.
- ^ Yu, Xinxian; Yao, Fengju; Huang, Wenjie; Xu, Dongyan; Chen, Chun (July 2022). "Enhanced radiative cooling paint with broken glass bubbles". Renewable Energy. 194: 129–136. doi:10.1016/j.renene.2022.05.094. S2CID 248972097 – via Elsevier Science Direct.
Radiative cooling does not consume external energy but rather harvests coldness from outer space as a new renewable energy source.
- ^ Ma, Hongchen (2021). "Flexible Daytime Radiative Cooling Enhanced by Enabling Three-Phase Composites with Scattering Interfaces between Silica Microspheres and Hierarchical Porous Coatings". ACS Appl. Mater. Interfaces. 13 (16): 19282–19290. arXiv:2103.03902. doi:10.1021/acsami.1c02145. PMID 33866783. S2CID 232147880 – via ACS Publications.
Daytime radiative cooling has attracted considerable attention recently due to its tremendous potential for passively exploiting the coldness of the universe as clean and renewable energy.
- ^ Bijarniya, Jay Prakash; Sarkar, Jahar; Maiti, Pralay (November 2020). "Review on passive daytime radiative cooling: Fundamentals, recent researches, challenges and opportunities". Renewable and Sustainable Energy Reviews. 133: 110263. doi:10.1016/j.rser.2020.110263. S2CID 224874019 – via Elsevier Science Direct.
Passive radiative cooling can be considered as a renewable energy source, which can pump heat to cold space and make the devices more efficient than ejecting heat at earth atmospheric temperature.
- ^ Bijarniya, Jay Prakash; Sarkar, Jahar; Maiti, Pralay (November 2020). "Review on passive daytime radiative cooling: Fundamentals, recent researches, challenges and opportunities". Renewable and Sustainable Energy Reviews. 133: 110263. doi:10.1016/j.rser.2020.110263. S2CID 224874019 – via Elsevier Science Direct.
- ^ Benmoussa, Youssef; Ezziani, Maria; Djire, All-Fousseni; Amine, Zaynab; Khaldoun, Asmae; Limami, Houssame (September 2022). "Simulation of an energy-efficient cool roof with cellulose-based daytime radiative cooling material". Materials Today: Proceedings. 72: 3632–3637. doi:10.1016/j.matpr.2022.08.411. S2CID 252136357 – via Elsevier Science Direct.
- ^ Khan, Ansar; Carlosena, Laura; Feng, Jie; Khorat, Samiran; Khatun, Rupali; Doan, Quang-Van; Santamouris, Mattheos (January 2022). "Optically Modulated Passive Broadband Daytime Radiative Cooling Materials Can Cool Cities in Summer and Heat Cities in Winter". Sustainability. 14 – via MDPI.
- ^ Anand, Jyothis; Sailor, David J.; Baniassadi, Amir (February 2021). "The relative role of solar reflectance and thermal emittance for passive daytime radiative cooling technologies applied to rooftops". Sustainable Cities and Society. 65: 102612. doi:10.1016/j.scs.2020.102612. S2CID 229476136 – via Elsevier Science Direct.
- ^ a b Heo, Se-Yeon; Ju Lee, Gil; Song, Young Min (June 2022). "Heat-shedding with photonic structures: radiative cooling and its potential". Journal of Materials Chemistry C. 10 (27): 9915–9937. doi:10.1039/D2TC00318J. S2CID 249695930 – via Royal Society of Chemistry.
- ^ a b Ahmed, Salman; Li, Zhenpeng; Javed, Muhammad Shahzad; Ma, Tao (September 2021). "A review on the integration of radiative cooling and solar energy harvesting". Materials Today: Energy. 21: 100776. doi:10.1016/j.mtener.2021.100776 – via Elsevier Science Direct.
- ^ Wang, Tong; Wu, Yi; Shi, Lan; Hu, Xinhua; Chen, Min; Wu, Limin (2021). "A structural polymer for highly efficient all-day passive radiative cooling". Nature Communications. 12 (365): 365. doi:10.1038/s41467-020-20646-7. PMC 7809060. PMID 33446648.
Accordingly, designing and fabricating efficient PDRC with sufficiently high solar reflectance (𝜌¯solar) (λ ~ 0.3–2.5 μm) to minimize solar heat gain and simultaneously strong LWIR thermal emittance (ε¯LWIR) to maximize radiative heat loss is highly desirable. When the incoming radiative heat from the Sun is balanced by the outgoing radiative heat emission, the temperature of the Earth can reach its steady state.
- ^ Chen, Meijie; Pang, Dan; Chen, Xingyu; Yan, Hongjie; Yang, Yuan (2022). "Passive daytime radiative cooling: Fundamentals, material designs, and applications". EcoMat. 4. doi:10.1002/eom2.12153. S2CID 240331557.
Passive daytime radiative cooling (PDRC) dissipates terrestrial heat to the extremely cold outer space without using any energy input or producing pollution. It has the potential to simultaneously alleviate the two major problems of energy crisis and global warming.
- ^ Munday, Jeremy (2019). "Tackling Climate Change through Radiative Cooling". Joule. 3 (9): 2057–2060. doi:10.1016/j.joule.2019.07.010. S2CID 201590290.
By covering the Earth with a small fraction of thermally emitting materials, the heat flow away from the Earth can be increased, and the net radiative flux can be reduced to zero (or even made negative), thus stabilizing (or cooling) the Earth.
- ^ Raman, Aaswath P.; Anoma, Marc Abou; Zhu, Linxiao; Raphaeli, Eden; Fan, Shanhui (2014). "Passive Radiative Cooling Below Ambient air Temperature under Direct Sunlight". Nature. 515 (7528): 540–544. Bibcode:2014Natur.515..540R. doi:10.1038/nature13883. PMID 25428501. S2CID 4382732 – via nature.com.
- ^ Yang, Yuan; Zhang, Yifan (2020). "Passive daytime radiative cooling: Principle, application, and economic analysis". MRS Energy & Sustainability. 7 (18). doi:10.1557/mre.2020.18. S2CID 220008145. Archived from the original on 27 September 2022. Retrieved 27 September 2022.