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.
Colum 1 +
Colum 2 +
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

2005

Levinson, Ronnen M., Hashem Akbari, Steven J. Konopacki, and Sarah E. Bretz."Inclusion of cool roofs in nonresidential Title 24 prescriptive requirements."Energy Policy 33.2 (2005) 151-170. DOI

1998

Akbari, Hashem, and Sarah E. Bretz."Cool systems for hot cities."Professional Roofing 32-35 (1998) 1-5.

Brown, Richard E., Celina S. Atkinson, Jeffrey L. Warner, Judy A. Roberson, Marla C. Sanchez, Sarah E. Bretz, and Jonathan G. Koomey."Developing Energy-Efficiency Packages for New Production Homes."1998 ACEEE Summer Study on Energy Efficiency in Buildings (1998).

Bretz, Sarah E., Hashem Akbari, and Arthur H. Rosenfeld."Practical issues for using solar-reflective materials to mitigate urban heat islands."Atmospheric Environment 32 (1998) 95-101. DOI

1997

Bretz, Sarah E., and Hashem Akbari."Long-term performance of high-albedo roof coatings."Energy and Buildings 25.2 (1997) 159-167. DOI

Akbari, Hashem, Sarah E. Bretz, Dan M. Kurn, and James W. Hanford."Peak power and cooling energy savings of high-albedo roofs."Energy and Buildings 25 (1997) 117-126. DOI

Berdahl, Paul H., and Sarah E. Bretz."Preliminary survey of the solar reflectance of cool roofing materials."Energy and Buildings 25 (1997) 149-158. DOI

1995

Rosenfeld, Arthur H., Hashem Akbari, Sarah E. Bretz, Beth L. Fishman, Dan M. Kurn, David J. Sailor, and Haider Taha."Mitigation of urban heat islands: materials, utility programs, updates."Energy and Buildings 22.3 (1995) 255-265. DOI

1994

Kurn, Dan M., Sarah E. Bretz, Benson Huang, and Hashem Akbari."The potential for reducing urban air temperatures and energy consumption through vegetative cooling." (1994). DOI

1993

Akbari, Hashem, Sarah E. Bretz, James W. Hanford, Dan M. Kurn, Beth L. Fishman, and Haider Taha."Monitoring peak power and cooling energy savings of shade trees and white surfaces in the Sacramento Municipal Utility District (SMUD) service area: data analysis, simulations, and results." (1993).

1992

Akbari, Hashem, Sarah E. Bretz, James W. Hanford, Arthur H. Rosenfeld, David J. Sailor, Haider Taha, and Willem Bos."Monitoring peak power and cooling energy savings of shade trees and white surfaces in the Sacramento Municipal Utility District (SMUD) service area: project design and preliminary results." (1992). DOI

Bretz, Sarah E., Hashem Akbari, Arthur H. Rosenfeld, and Haider Taha."Implementation of solar-reflective surfaces: materials and utility programs." (1992) 67. DOI