About Us +
Researchers in the Building Technology & Urban Systems Division (BTUS) at Lawrence Berkeley National Laboratory develop data and technologies that increase energy efficiency and improve the health, safety and comfort of building occupants, in the United States and worldwide.

We work closely with industry partners, academics and government officials to achieve these goals, and share our research widely
Research +
We are at the forefront of cutting-edge research that redefines building technology and explores all areas of urban systems.

We have been leaders for decades in developing energy-efficient windows, improving indoor air quality, coming up with new ideas to fix the nation's electricity grid, and so much more.

Visit our research areas at the right to find out more.
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Publications +
Enjoy presentations from Building Technology & Urban systems research experts on a wide variety of topics in the areas of building energy efficiency, the electricity grid and how it relates to buildings and much more.
- Presentations
News
Tools & Guides +
Explore our tools, guidebooks and software and download for free.

We offer a variety of technologies designed to simulate and model real-world circumstances to assist in energy-saving programs and help building owners build better buildings. These tools can help calculate performance of building systems like windows and shades, help consumers and builders pick the best windows for a variety of applications and much more.

Publications

Publications By Research Area

2012

Levinson, Ronnen M.."The Case for Cool Roofs." (2012).

2011

Levinson, Ronnen M., Heng Pan, George A. Ban-Weiss, Pablo J. Rosado, Riccardo Paolini, and Hashem Akbari."Potential benefits of solar reflective car shells: Cooler cabins, fuel savings and emission reductions."Applied Energy 88.12 (2011) 4343-4357. DOI

Menon, Surabi, and Ronnen M. Levinson."Cool roofs and global cooling: a response to Jacobson & Ten Hoeve (2011)." (2011).

Sleiman, Mohamad, George A. Ban-Weiss, Haley E. Gilbert, David François, Paul H. Berdahl, Thomas W. Kirchstetter, Hugo Destaillats, and Ronnen M. Levinson."Soiling of building envelope surfaces and its effect on solar reflectance—Part I: Analysis of roofing product databases."Solar Energy Materials and Solar Cells 95.12 (2011) 3385-3399. DOI

Millstein, Dev, and Surabi Menon."Regional climate consequences of large-scale cool roof and photovoltaic array deployment."Environmental Research Letters 6.3 (2011).

2010

Levinson, Ronnen M., Hashem Akbari, and Paul H. Berdahl."Measuring solar reflectance—Part I: Defining a metric that accurately predicts solar heat gain."Solar Energy 84.9 (2010) 1717-1744. DOI

Levinson, Ronnen M., Hashem Akbari, and Paul H. Berdahl."Measuring solar reflectance—Part II: Review of practical methods."Solar Energy 84.9 (2010) 1745-1759. DOI

Levinson, Ronnen M., Hashem Akbari, Paul H. Berdahl, Kurt Wood, Wayne Skilton, and Jerry Petersheim."A novel technique for the production of cool colored concrete tile and asphalt shingle roofing products."Solar Energy Materials and Solar Cells 94.6 (2010) 946-954. DOI

Levinson, Ronnen M., and Hashem Akbari."Potential benefits of cool roofs on commercial buildings: conserving energy, saving money, and reducing emission of greenhouse gases and air pollutants."Energy Efficiency 3.1 (2010) 53-109. DOI

Menon, Surabi, Hashem Akbari, Sarith Mahanama, Igor Sednev, and Ronnen M. Levinson."Radiative forcing and temperature response to changes in urban albedos and associated CO₂ offsets."Environmental Research Letters 5.1 (2010). DOI

2009

Levinson, Ronnen M., Hashem Akbari, Melvin Pomerantz, and Smita Gupta."Solar access of residential rooftops in four California cities."Solar Energy 83.12 (2009) 2120-2135. DOI

Barringer, Felicity."By Degrees: White Roofs Catch On as Energy Cost Cutters."The New York Times (2009).

Akbari, Hashem, Surabi Menon, and Arthur H. Rosenfeld."Global cooling: increasing world-wide urban albedos to offset CO₂."Climatic Change 94.3-4 (2009) 275-286. DOI

Akbari, Hashem, and Arthur H. Rosenfeld."Cool roofs could save money, save planet."KGO-TV (abc7news) (2009).

Akbari, Hashem."Hashem Akbari speaks to BBC Radio World Service about global cooling."BBC (2009).

Rosenfeld, Arthur H.."Painting the town white: California Energy Commissioner, Art Rosenfeld, explains the benefits of cool roofs."National Public Radio (2009).

2008

Akbari, Hashem, and Arthur H. Rosenfeld."White roofs cool the world, directly offset CO₂ and delay global warming."Research Highlights (2008).

Akbari, Hashem, Surabi Menon, and Arthur H. Rosenfeld."Equivalent CO₂ avoided by reflective roofs and pavements in California."Memo to California Air Resources Board (2008).

Akbari, Hashem, Ronnen M. Levinson, and Stephanie Stern."Procedure for measuring the solar reflectance of flat or curved roofing assemblies."Solar Energy 82.7 (2008) 648-655. DOI

Akbari, Hashem, and Ronnen M. Levinson."Status of cool roof standards in the United States." (2008).

Berdahl, Paul H., Hashem Akbari, Jeffry Jacobs, and Frank Klink."Surface roughness effects on the solar reflectance of cool asphalt shingles."Solar Energy Materials and Solar Cells 92.4 (2008) 482-489. DOI

Berdahl, Paul H., Hashem Akbari, Ronnen M. Levinson, and William A. Miller."Weathering of roofing materials – An overview."Construction and Building Materials 22.4 (2008) 423-433. DOI

Levinson, Ronnen M., Hashem Akbari, Melvin Pomerantz, and Smita Gupta."Estimating the solar access of typical residential rooftops: A case study in San Jose, CA."Solar 2008 (2008).

Berdahl, Paul H., and Hashem Akbari."Evaluation of titanium dioxide as a photocatalyst for removing air pollutants." (2008).

Wray, Craig P., and Hashem Akbari."The effects of roof reflectance on air temperatures surrounding a rooftop condensing unit."Energy and Buildings 40.1 (2008) 11-28. DOI