Buildings and Utilities Project Manager Nils Petermann (npettermann@ase.org) presented specific Alliance experience in windows market transformation through the Efficient Windows Collaborative (EWC). Nils directs the EWC, and his expertise includes window energy efficiency standards and technologies as well as analysis of the energy savings achievable through building codes.

1. Promoting Energy Efficiency Standards
and Technologies for Windows
February 23, 2010
Nils Petermann
npetermann@ase.org
Alliance to Save Energy
www.ase.org
www.efficientwindows.org / www.commercialwindows.org
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2. The Impact of Window Performance
In the United States, about 23%
of heating energy use and about
34% of cooling energy use is
due to windows.
With current, cost-effective
technologies, about half of this
energy use can be saved.
Source: Lawrence Berkeley National Laboratory
Source: U.S. Department of Energy
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3. What Makes an Energy-Efficient Window?
Energy-
$0 $200 $400 $600 $800
Low-E coating
$0 $200 $400 $600 $800
Gas fill
Warm-edge spacers
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4. Window Energy Parameters
Heat Transfer Daylight Access
U-Factor Visible
Transmittance
(VT)
Solar Heat Gain Infiltration
Solar Heat Gain Air Leakage
Coefficient (AL)
(SHGC)
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5. The Information Source for
Window Energy Properties:
The NFRC Label
The National Fenestration Rating Council
(NFRC) has established a voluntary national
energy performance rating and labeling system
for fenestration products.
NFRC ratings show the complete aggregated
performance of the whole product, including:
• frame
• glazing
• spacer
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6. The NFRC Label is the Basis for Energy
Code Compliance and ENERGY STAR
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7. The Efficient Windows Collaborative
Help with sorting through the complexities of window performance
Residential Windows Info
www.efficientwindows.org
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8. The Efficient Windows Collaborative
Help with sorting through the complexities of window performance
Commercial Windows Info www.commercialwindows.org
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9. Thank You
Nils Petermann John Carmody
Alliance to Save Energy University of Minnesota
(202) 530-2254 carmo001@umn.edu
npetermann@ase.org
Steve Selkowitz
Kerry Haglund LBNL
University of Minnesota seselkowitz@lbl.gov
(612) 626-9478
khaglund@umn.edu Dariush Arasteh
LBNL
d_arasteh@lbl.gov
www.efficientwindows.org
www.commercialwindows.umn.edu
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