Roof-integrated radiative air-cooling system to achieve cooler attic for building energy saving

Zhao, Dongliang; Aili, Ablimit; Yin, Xiaobo; Tan, Gang; Yang, Ronggui

doi:10.1016/j.enbuild.2019.109453

Title: Roof-integrated radiative air-cooling system to achieve cooler attic for building energy saving

Journal Article · Mon Sep 23 00:00:00 EDT 2019 · Energy and Buildings

DOI:https://doi.org/10.1016/j.enbuild.2019.109453· OSTI ID:1799028

Zhao, Dongliang ^[1]; Aili, Ablimit ^[1]; Yin, Xiaobo ^[1]; Tan, Gang ^[2]; Yang, Ronggui ^[1]

Univ. of Colorado, Boulder, CO (United States)
Univ. of Wyoming, Laramie, WY (United States)

The building attic usually subjects to substantial solar heat gain and has much higher temperature compared to the conditioned living space during the day, especially in summer and in hot areas. Reducing attic temperature can reduce cooling energy consumption in buildings. However, conventional techniques such as cool roof or attic ventilation, suffer from either heating penalty in winter or limited attic temperature reduction. In this work, a new roof-integrated radiative air-cooling system is introduced, which couples radiative sky cooling with attic ventilation to reduce attic temperature. A radiative air cooler with 1.08 m² surface area is constructed using a recently developed daytime radiative sky cooling metamaterial [Zhai et al., Science 355, pp. 1062–1066, 2017]. Experimental tests show that sub-ambient air cooling is achieved throughout 24-h day-and-night cycle in a summer day with clear sky conditions. Depending on air flow rates, measured sub-ambient temperature reductions of air are 5–8°C at night and 3–5°C at noon under direct sunlight, respectively. An in-house model is first developed for the radiative air-cooling system, the model is then coupled with EnergyPlus to study annual energy saving of buildings. The performance of the radiative air-cooling system is compared with three reference systems: shingle roof, attic ventilation, and cool roof. Results show that for a single-family house, attic temperature can be substantially reduced by 15.5–21.0°C, varying with attic insulation level, compared to shingle roof on typical summer days. Compared to a shingle roof (solar reflectance 0.25, thermal emittance 0.9) residential building with attic insulations of R-30 (RSI-5.28), R-10 (RSI-1.76), and R-0.8 (RSI-0.14), the roof-integrated radiative air-cooling system can achieve annual cooling energy savings of 0.4–1.5 kWh/m² (4.6–18.8%), 1.2–3.6 kWh/m² (10.2–41.4%), and 3.7–11.8 kWh/m² (26.5–76.1%) respectively.

View Accepted Manuscript (DOE)

View Accepted Manuscript (Publisher)

Cite

Export

Save

Research Organization:: Univ. of Colorado, Boulder, CO (United States)

Sponsoring Organization:: USDOE Advanced Research Projects Agency - Energy (ARPA-E)

Grant/Contract Number:: AR0000580

OSTI ID:: 1799028

Alternate ID(s):: OSTI ID: 1779558

Journal Information:: Energy and Buildings, Vol. 203; ISSN 0378-7788

Publisher:: ElsevierCopyright Statement

Country of Publication:: United States

Language:: English

References (30)

Describing the uncertainties in experimental results Moffat, Robert J. Experimental Thermal and Fluid Science, Vol. 1, Issue 1 https://doi.org/10.1016/0894-1777(88)90043-X	journal	January 1988
Temperature reduction in attic and ceiling via insulation of several passive roof designs Ong, K. S. Energy Conversion and Management, Vol. 52, Issue 6 https://doi.org/10.1016/j.enconman.2010.12.044	journal	June 2011
The potential for cool roofs to improve the energy efficiency of single storey warehouse-type retail buildings in Australia: A simulation case study Seifhashemi, M.; Capra, B. R.; Milller, W. Energy and Buildings, Vol. 158 https://doi.org/10.1016/j.enbuild.2017.11.034	journal	January 2018
A review of benefits and limitations of static and switchable cool roof systems Testa, Jenna; Krarti, Moncef Renewable and Sustainable Energy Reviews, Vol. 77 https://doi.org/10.1016/j.rser.2017.04.030	journal	September 2017
Photovoltaic–thermal collectors for night radiative cooling of buildings Eicker, Ursula; Dalibard, Antoine Solar Energy, Vol. 85, Issue 7 https://doi.org/10.1016/j.solener.2011.03.015	journal	July 2011
Passive radiative cooling below ambient air temperature under direct sunlight Raman, Aaswath P.; Anoma, Marc Abou; Zhu, Linxiao Nature, Vol. 515, Issue 7528, p. 540-544 https://doi.org/10.1038/nature13883	journal	November 2014
Measured temperature reductions and energy savings from a cool tile roof on a central California home Rosado, Pablo J.; Faulkner, David; Sullivan, Douglas P. Energy and Buildings, Vol. 80 https://doi.org/10.1016/j.enbuild.2014.04.024	journal	September 2014
Full-scale measurements of wind-induced convective heat transfer from a roof-mounted flat plate solar collector Sharples, S.; Charlesworth, P. S. Solar Energy, Vol. 62, Issue 2 https://doi.org/10.1016/S0038-092X(97)00119-9	journal	February 1998
Subambient Cooling of Water: Toward Real-World Applications of Daytime Radiative Cooling Zhao, Dongliang; Aili, Ablimit; Zhai, Yao Joule, Vol. 3, Issue 1 https://doi.org/10.1016/j.joule.2018.10.006	journal	January 2019
A review of the potential of attic ventilation by passive and active turbine ventilators in tropical Malaysia Al-Obaidi, Karam M.; Ismail, Mazran; Abdul Rahman, Abdul Malek Sustainable Cities and Society, Vol. 10 https://doi.org/10.1016/j.scs.2013.10.001	journal	February 2014
Simulating the effects of cool roof and PCM (phase change materials) based roof to mitigate UHI (urban heat island) in prominent US cities Roman, Kibria K.; O'Brien, Timothy; Alvey, Jedediah B. Energy, Vol. 96 https://doi.org/10.1016/j.energy.2015.11.082	journal	February 2016
Energy saving and economic analysis of a new hybrid radiative cooling system for single-family houses in the USA Zhang, Kai; Zhao, Dongliang; Yin, Xiaobo Applied Energy, Vol. 224 https://doi.org/10.1016/j.apenergy.2018.04.115	journal	August 2018
A case study for the effectiveness of solar-powered attic ventilation fans Yu, Ok-Youn; Moore, Stacy Energy Efficiency, Vol. 8, Issue 4 https://doi.org/10.1007/s12053-014-9315-1	journal	November 2014
Performance assessment of a photonic radiative cooling system for office buildings Wang, Weimin; Fernandez, Nick; Katipamula, Srinivas Renewable Energy, Vol. 118 https://doi.org/10.1016/j.renene.2017.10.062	journal	April 2018
Scalable-manufactured randomized glass-polymer hybrid metamaterial for daytime radiative cooling Zhai, Yao; Ma, Yaoguang; David, Sabrina N. Science, Vol. 355, Issue 6329 https://doi.org/10.1126/science.aai7899	journal	February 2017
Performance improvement of a double-pass solar air heater with fins and baffles under recycling operation Ho, Chii-Dong; Chang, Hsuan; Wang, Rei-Chi Applied Energy, Vol. 100 https://doi.org/10.1016/j.apenergy.2012.03.065	journal	December 2012
Thermal performance analysis of residential attics containing high performance aerogel-based radiant barriers Kosny, Jan; Fontanini, Anthony D.; Shukla, Nitin Energy and Buildings, Vol. 158 https://doi.org/10.1016/j.enbuild.2017.10.081	journal	January 2018
Radiative sky cooling: Fundamental principles, materials, and applications Zhao, Dongliang; Aili, Ablimit; Zhai, Yao Applied Physics Reviews, Vol. 6, Issue 2 https://doi.org/10.1063/1.5087281	journal	June 2019
Thermal modeling of a combined system of photovoltaic thermal (PV/T) solar water heater Dubey, Swapnil; Tiwari, G. N. Solar Energy, Vol. 82, Issue 7 https://doi.org/10.1016/j.solener.2008.02.005	journal	July 2008
Wind heat transfer coefficient in solar collectors in outdoor conditions Kumar, Suresh; Mullick, S. C. Solar Energy, Vol. 84, Issue 6 https://doi.org/10.1016/j.solener.2010.03.003	journal	June 2010
A study of a polymer-based radiative cooling system Meir, M. G.; Rekstad, J. B.; LØvvik, O. M. Solar Energy, Vol. 73, Issue 6 https://doi.org/10.1016/S0038-092X(03)00019-7	journal	December 2002
Integration of thermal insulation coating and moving-air-cavity in a cool roof system for attic temperature reduction Yew, M. C.; Ramli Sulong, N. H.; Chong, W. T. Energy Conversion and Management, Vol. 75 https://doi.org/10.1016/j.enconman.2013.06.024	journal	November 2013
Cooling performance of nocturnal radiative cooling combined with microencapsulated phase change material (MPCM) slurry storage Zhang, Shuo; Niu, Jianlei Energy and Buildings, Vol. 54 https://doi.org/10.1016/j.enbuild.2012.07.041	journal	November 2012
Development of a single-phase thermosiphon for cold collection and storage of radiative cooling Zhao, Dongliang; Martini, Christine Elizabeth; Jiang, Siyu Applied Energy, Vol. 205 https://doi.org/10.1016/j.apenergy.2017.08.057	journal	November 2017
Attic baffle size and vent configuration impacts on attic ventilation Iffa, Emishaw; Tariku, Fitsum Building and Environment, Vol. 89 https://doi.org/10.1016/j.buildenv.2015.01.028	journal	July 2015
Direct and indirect effects of high-albedo roofs on energy consumption and thermal comfort of residential buildings Baniassadi, Amir; Sailor, David J.; Crank, Peter J. Energy and Buildings, Vol. 178 https://doi.org/10.1016/j.enbuild.2018.08.048	journal	November 2018
Conceptual development of a building-integrated photovoltaic–radiative cooling system and preliminary performance analysis in Eastern China Zhao, Bin; Hu, Mingke; Ao, Xianze Applied Energy, Vol. 205 https://doi.org/10.1016/j.apenergy.2017.08.011	journal	November 2017
Hierarchically porous polymer coatings for highly efficient passive daytime radiative cooling Mandal, Jyotirmoy; Fu, Yanke; Overvig, Adam C. Science, Vol. 362, Issue 6412 https://doi.org/10.1126/science.aat9513	journal	September 2018
Estimating the effect of using cool coatings on energy loads and thermal comfort in residential buildings in various climatic conditions Synnefa, A.; Santamouris, M.; Akbari, H. Energy and Buildings, Vol. 39, Issue 11 https://doi.org/10.1016/j.enbuild.2007.01.004	journal	November 2007
Experimental in-lab and in-field analysis of waterproof membranes for cool roof application and urban heat island mitigation Pisello, A. L.; Castaldo, V. L.; Pignatta, G. Energy and Buildings, Vol. 114 https://doi.org/10.1016/j.enbuild.2015.05.026	journal	February 2016

Similar Records

TASK 2.5.7 FIELD EXPERIMENTS TO EVALUATE COOL-COLORED ROOFING

Technical Report · Mon Mar 01 00:00:00 EST 2010 · OSTI ID:1799028

Miller, William A; Cherry, Nigel J; Allen, Richard Lowell; +5 more

Performance evaluation of a metamaterial-based new cool roof using improved Roof Thermal Transfer Value model

Journal Article · Mon May 06 00:00:00 EDT 2019 · Applied Energy · OSTI ID:1799028

Fang, Hong; Zhao, Dongliang; Yuan, Jinchao; +4 more

PERFORMANCE EVALUATION OF A SUSTAINABLE AND ENERGY EFFICIENT RE-ROOFING TECHNOLOGY USING FIELD-TEST DATA

Conference · Sat Jan 01 00:00:00 EST 2011 · OSTI ID:1799028

Biswas, Kaushik; Miller, William A; Childs, Phillip W; +2 more

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
radiative sky cooling
attic cooling
attic ventilation
building energy saving

Title: Roof-integrated radiative air-cooling system to achieve cooler attic for building energy saving

Citation Formats

References (30)

Similar Records

Related Subjects