Technical Brief

Initial Study on Controllable Roofing System to Tailor Building Solar Loads for Increased HVAC Efficiency

[+] Author and Article Information
Daniel M. Wolfe

Department of Electrical
and Computer Engineering,
University of Delaware,
140 Evans Hall,
Newark, DE 19716
e-mail: wolfedm@udel.edu

Keith W. Goossen

Department of Electrical
and Computer Engineering,
University of Delaware,
107 Evans Hall,
Newark, DE 19716
e-mail: goossen@udel.edu

Contributed by the Solar Energy Division of ASME for publication in the JOURNAL OF SOLAR ENERGY ENGINEERING: INCLUDING WIND ENERGY AND BUILDING ENERGY CONSERVATION. Manuscript received September 3, 2014; final manuscript received April 3, 2015; published online May 19, 2015. Assoc. Editor: Jorge E. Gonzalez.

J. Sol. Energy Eng 137(4), 044503 (Aug 01, 2015) (3 pages) Paper No: SOL-14-1251; doi: 10.1115/1.4030402 History: Received September 03, 2014; Revised April 03, 2015; Online May 19, 2015

Space heating and cooling account for a significant percentage of a building's overall energy usage profile. The construction of a building's envelope is an essential component that impacts the overall heating and cooling load. For many years, flat roofs were covered with low albedo materials such as asphalt or modified bitumen, which can reach temperatures of 60 °C–80 °C during summer months. More recently, alternative technologies, such as “white roofs,” have been put forth to mitigate the problem of unwanted thermal gain. However, these traditional roofing materials and recent innovations are passive structures and only promote seasonal benefits. This paper proposes and demonstrates the concept of a controllable reflectance roofing system that can tailor solar loads to desired heating or cooling, significantly reducing overall space heating and cooling energy requirements and costs.

Copyright © 2015 by ASME
Your Session has timed out. Please sign back in to continue.


Bretz, S., Akbari, H., and Rosenfeld, A., 1998, “Practical Issues for Using Solar-Reflective Materials to Mitigate Urban Heat Islands,” Atmos. Environ., 32(1), pp. 95–101. [CrossRef]
Gaffin, S., Rosenzweig, C., Eichenbaum-Pikser, J., Khanbilvardi, R., and Susca, T., 2010, “A Temperature and Seasonal Energy Analysis of Green, White, and Black Roofs,” Center for Climate Systems Research, Columbia University, New York, Technical Report No. http://www.coned.com/newsroom/pdf/Columbia%20study%20on%20Con%20Edisons%20roofs.pdf
Carlson, J., Delgado, A. H., Rosenow, E., Barnhardt, K., and Paroli, R. M., 2006, “Performance Evaluation of Unexposed and Field-Exposed Thermoplastic Polyolefin (TPO) Roof Membranes,” Proceedings of the Roof Consultants Institute 21st International Convention, Vol. 21, Western States Roofing Contractors Association and National Research Council of Canada, Institute for Research in Construction, pp. 59–76. http://www.coned.com/newsroom/pdf/Columbia%20study%20on%20Con%20Edisons%20roofs.pdf
McIlvain, J., Barkaszi, S., Beal, D., and Anello, M., 2000, “Laboratory Testing of Reflectance Properties of Roofing Materials,” Florida Solar Energy Center (FSEC), Cocoa, FL, Technical Report No. FSEC-CR-670-00.
Akbari, H., Bretz, S., Kurn, D. M., and Hanford, J., 1997, “Peak Power and Cooling Energy Savings of High-Albedo Roofs,” Energy Build., 25(2), pp. 117–126. [CrossRef]
Parker, D., Stephen Barkaszi, J., Chandra, S., and Beal, D., 1995, “Measured Cooling Energy Savings From Reflective Roofing Systems in Florida: Field and Laboratory Research Results,” Florida Solar Energy Center (FSEC), Cocoa, FL, Technical Report No. FSEC-PF-293-95.
Parker, D. S., and Barkaszi, S. F., Jr., 1997, “Roof Solar Reflectance and Cooling Energy Use: Field Research Results From Florida,” Energy Build., 25(2), pp. 105–115. [CrossRef]
Levinson, R. M., and Akbari, H., 2010, “Potential Benefits of Cool Roofs on Commercial Buildings: Conserving Energy, Saving Money, and Reducing Emission of Greenhouse Gases and Air Pollutants,” Energy Effic., 3(1), pp. 53–109. [CrossRef]
Boixo, S., Diaz-Vicente, M., Colmenar, A., and Castro, M. A., 2012, “Potential Energy Savings From Cool Roofs in Spain and Andalusia,” Energy, 38(1), pp. 425–438. [CrossRef]
Synnefa, A., Santamouris, M., and Akbari, H., 2007, “Estimating the Effect of Using Cool Coatings on Energy Loads and Thermal Comfort in Residential Buildings in Various Climatic Conditions,” Energy Build., 39(11), pp. 1167–1174. [CrossRef]
Roche, P. L., and Berardi, U., 2014, “Comfort and Energy Savings With Active Green Roofs,” Energy Build., 82, pp. 492–504. [CrossRef]


Grahic Jump Location
Fig. 4

Normal-to-normal transmission of power for tribead and pony bead packed shingles with interstitial mediums of air and water

Grahic Jump Location
Fig. 3

Cross section of the simulated model and an illuminated shingle on the solar simulator

Grahic Jump Location
Fig. 2

Shingle modes of operation: high albedo (top-left and top-right), high absorbance (bottom-left and bottom-right)

Grahic Jump Location
Fig. 1

Simulated results of increasing roof albedo from 0.10 to 0.40 for seven U.S. cities [9]




Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In