Methods of creating solar-reflective nonwhite surfaces and their application to residential roofing materials

Levinson, Ronnen; Berdahl, Paul; Akbari, Hashem; Miller, William A.; Joedicke, Ingo; Reilly, Joseph; Suzuki, Yoshi; Vondran, Michelle

doi:10.1016/j.solmat.2006.06.062

Cited by 278 publications

(116 citation statements)

References 4 publications

Supporting

Mentioning

111

Contrasting

Unclassified

Order By: Relevance

“…Solar radiation is the radiant energy within a broad region of the electromagnetic spectrum that includes ultraviolet (UV), visible (light) and infrared radiation increase the intensity of reflected UV radiation [129]. UV radiation is harmful to living cells and can result in sunburn, increased rate of aging of the skin, and skin cancer, with its damage accumulating over years [130].…”

Section: Thermal Comfort and Health Risk Considerationmentioning

confidence: 99%

Environmental impacts of reflective materials: Is high albedo a ‘silver bullet’ for mitigating urban heat island?

Yang

Wang

Kaloush

2015

Renewable and Sustainable Energy Reviews

217

View full text Add to dashboard Cite

Studies on urban heat island (UHI) have been more than a century after the phenomenon was first discovered in the early 1800s. UHI emerges as the source of many urban environmental problems and exacerbates the living environment in cities. Under the challenges of increasing urbanization and future climate changes, there is a pressing need for sustainable adaptation/mitigation strategies for UHI effects, one popular option being the use of reflective materials. While it is introduced as one effective method to reduce temperature and energy consumption in cities, its impacts on multi-dimensional environmental sustainability and large-scale non-local effect are inadequately explored. This paper provides a synthetic overview of potential environmental impacts of reflective materials at a variety of scales, ranging from energy load on a single building to regional hydroclimate. The review shows that mitigation potential of reflective materials depends on a portfolio of factors, including building characteristics, urban environment, meteorological and geographical conditions, to name a few.Precaution needs to be exercised by city planners and policy makers for large-scale deployment of reflective materials before their environmental impacts, especially on regional hydroclimates, are better understood. In general, it is recommended that optimal strategy for UHI needs to be determined on a city-by-city basis, rather than adopting a "one-solution-fits-all" strategy.

show abstract

Section: Thermal Comfort and Health Risk Considerationmentioning

confidence: 99%

Environmental impacts of reflective materials: Is high albedo a ‘silver bullet’ for mitigating urban heat island?

Yang

Wang

Kaloush

2015

Renewable and Sustainable Energy Reviews

217

View full text Add to dashboard Cite

show abstract

“…Pigments possessing low absorbance in the NIR region can be considered as ideal for cool coatings, provided the background or the material on which coated is NIR reflective [2]. For instance, cobalt aluminate (absorption coefficient, K ~150 mm 1 , backscattering coefficient, S ~30 mm 1 ) has been reported to have undesirable absorption and weak NIR scattering in the 1200-1600 nm range [6]. To obtain cool coating features, cobalt aluminate needs to be coated on NIR reflective substrates such as white, which makes the color lighter [1].…”

Section: Resultsmentioning

confidence: 99%

“…With applications in military, construction, plastic, leather and ink industries, near infra-red reflective non-white pigments are becoming more and more relevant [1][2][3][4][5]. They are expected to reflect almost 49% of near-infrared radiation from the sun (=750-2500 nm) and thus reduce energy requirements for cooling of interiors of buildings, automobiles, etc [6]. They also have applications such  as camouflage pigments for military uniforms, IR reflective polymeric screens for green houses, etc [7].…”

Section: Introductionmentioning

confidence: 99%

“…Some of the pigments or pigment formulations reported as useful in NIR reflective coatings such as the azo pigments and those containing Cr(VI) and cadmium are today a subject of eco-bans and need to be phased out [6]. Amongst 2 ] need replacement in modern context due to their low durability, poor stability and low level of environmental acceptability.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Rare earth doped cobalt aluminate blue as an environmentally benign colorant

2012

View full text Add to dashboard Cite

Increasing energy cost calls for exterior coatings with high near infra-red reflectance, so as to reduce heat absorption and in turn cost of air-conditioning. While modulations of substrate, use of white metal oxides as pigments or under-layers has been reported in past, reports on metal oxide or doped metal oxide pigments with high NIR reflectance is scarce. We report for the first time a blue colored cobalt aluminate type pigment prepared through doping of cerium, praseodymium or neodymium. CIELAB color measurements and calculation of E indicated that the Nd doped sample had crystal size of (36±1) nm, bandgap value of (2.4±0.2) eV and color coordinates similar to that of cobalt aluminate. The molar ratio as estimated by EDX was found to be Al : Cu : Co : Ce : Nd : O= 2 : 0.06 : 0.06 : 0.012 : 0.000 12 : 6.18. The pigment was found to have potential applications as a cool blue colorant, owing to changes in optical properties arising out of crystal chemistry changes. Incorporation of rare earth metal ions was found to enhance the NIR reflectance by 10%, when compared to a conventional cobalt aluminate pigment. The oxide has been well characterized and its performance as a pigment evaluated. We have proposed that changes in crystal lattice when neodymium enters into Ce 4+ sites enhance the NIR reflectance by about 9% as against the entry of praseodymium.

show abstract

“…Estes são intitulados "frios" porque possuem índices elevados de refletância (habilidade de refletir radiação solar) e alta emissividade térmica (habilidade de irradiar calor) sob incidência de radiação solar (LEVINSON et al, 2007). Os índices de refletância e emitância variam de 0 a 1.…”

Section: Introductionunclassified

Pintura à base de cal como alternativa de revestimento frio

2014

View full text Add to dashboard Cite

Os centros urbanos vêm sofrendo alterações climáticas oriundas do fenômeno das ilhas de calor. Como consequência, há o aumento na demanda de energia para condicionamento térmico, além de causar desconforto em habitações que não fazem uso de ar-condicionado. Revestimento frio é uma alternativa que pode minimizar os efeitos da ilha de calor, pois possui capacidade de refletir a luz solar incidente, bem como reemitir parte do calor absorvido pela superfície para o ambiente. Tradicionalmente, superfícies brancas são responsáveis por alto poder de reflexão. Partindo desse conceito, o presente trabalho mediu as propriedades de refletância e emissividade térmica de superfícies pintadas com tinta à base de cal, em diferentes números de demãos, sobre substratos distintos. Além dessas propriedades, foi feita uma análise da capacidade de cobertura das amostras nas condições úmida e seca. Os resultados de refletância variaram de 0,56 a 0,83, dependendo do número de demãos e do tipo de substrato. A emissividade térmica manteve-se com índice de, em média, 0,97, independentemente do tipo de substrato e demãos de pintura. Por fim, percebeu-se um contraste expressivo entre as superfícies sob as condições úmida e seca. Os resultados demonstram que a pintura de cal atende aos requisitos de refletância e emissividade térmica para um revestimento frio.

show abstract

Methods of creating solar-reflective nonwhite surfaces and their application to residential roofing materials

Cited by 278 publications

References 4 publications

Environmental impacts of reflective materials: Is high albedo a ‘silver bullet’ for mitigating urban heat island?

Environmental impacts of reflective materials: Is high albedo a ‘silver bullet’ for mitigating urban heat island?

Rare earth doped cobalt aluminate blue as an environmentally benign colorant

Pintura à base de cal como alternativa de revestimento frio

Contact Info

Product

Resources

About