New Study Proves Awnings Can Save on Energy Costs for Homeowners

ROSEVILLE, Minn., Feb. 21 /PRNewswire/ -- A new study found that awnings can provide significant savings on cooling costs and on peak electrical demand by reducing solar gain through home windows. The study, Awnings in Residential Buildings: The Impact on Energy Use and Peak Demand, was conducted by the Center for Sustainable Building Research at the University of Minnesota.

The Professional Awning Manufacturers Association (PAMA) funded the study to determine if awnings are a viable means of reducing energy and air conditioner usage in the home. Most U.S. residential neighborhoods do not have a significant number of awnings, unlike Europe, where awnings are used to reduce air conditioning use in the summer. The study investigated the energy savings for single family homes and the reduction of energy use during peak periods.

In the first phase of the study, awning impacts were measured in seven U.S. cities across various climates, including Minneapolis, Boston, Seattle, Albuquerque, Phoenix, St. Louis and Sacramento. The study revealed that in all cities for all window orientations tested (see tables on page 2), there were significant energy savings in cooling costs and peak electricity demand as a result of using window awnings. The amount of energy saved varies, depending on the number of windows, types of glass in the windows and window orientation. Phase two of the study is due for release in the spring and will include additional cities.

Specifically, the study found that in Phoenix, Ariz., a warm climate, window awnings can reduce the use of home cooling energy as much as 26 percent compared to a home with completely unshaded windows. In St. Louis, Mo., a mixed climate, awnings can reduce the use of cooling energy as much as 23 percent. Similarly, in Boston, Mass., a cold climate, awnings can reduce the need for cooling energy as much as 33 percent.

"Depending on the region a home is in, awnings can save home owners more than $100 annually, but energy savings like this are valuable beyond reducing homeowners' expenses," said Michelle Sahlin, managing director of PAMA. "When numerous homeowners reduce their need for energy, there is less demand for energy at the times of peak usage, resulting in overall savings to utility companies and the public from a decreased need to supply generating capacity."

Researchers used a specialized computer program to investigate variables in conjunction with a standard awning with sides. The variables included geographic location, window orientation and exposure, winter and summer usage, and window type.

For more information about the study, contact Michelle Sahlin at mesahlin@ifai.com.

About PAMA

The Professional Awning Manufacturers Association (PAMA), a division of IFAI, is made up of awning fabricators and suppliers in the awning industry. PAMA maintains two Web sites: http://www.awninginfo.com/ , which focuses on association members and commercial awning use, and http://www.awningstoday.com/ , which educates consumers about awnings and awning benefits.

The Industrial Fabrics Association International (IFAI) proactively represents and promotes the products and innovations of the specialty fabrics industry worldwide. http://www.ifai.com/

  Summary of Awning Impacts In Seven U.S. Cities:

  Table 1: Equal Window Orientation

                       Percent of Cooling       Percent of Peak
  City                     Energy Saved       Cooling Energy Saved
  Minneapolis                 25-26%                   9-10%
  Boston                      23-24%                  17-22%
  Seattle                     60-70%                  35-39%
  Albuquerque                 28-31%                  11-17%
  Phoenix                     14-21%                   9-13%
  St. Louis                   14-17%                  11-16%
  Sacramento                  37-39%                  15-21%

Table 2: East Window Orientation (A majority of windows are located on the east side of the home.)

                       Percent of Cooling          Percent of Peak
  City                    Energy Saved           Cooling Energy Saved
  Minneapolis                 29-31%                  22-23%
  Boston                      30-32%                  28-37%
  Seattle                     51-69%                     23%
  Albuquerque                 34-39%                  12-27%
  Phoenix                     15-22%                    4-6%
  St. Louis                   18-21%                  13-23%
  Sacramento                  36-39%                   9-13%

Table 3: South Window Orientation (A majority of windows are located on the south side of the home.)

                      Percent of Cooling          Percent of Peak
  City                    Energy Saved          Cooling Energy Saved
  Minneapolis                 28-34%                   5-22%
  Boston                      24-33%                  22-36%
  Seattle                     71-80%                  44-53%
  Albuquerque                 28-33%                   9-19%
  Phoenix                     15-22%                   3-11%
  St. Louis                    8-18%                  17-30%
  Sacramento                  40-45%                  10-26%

Table 4: West Window Orientation (A majority of windows are located on the west side of the home.)

                      Percent of Cooling           Percent of Peak
  City                   Energy Saved            Cooling Energy Saved
  Minneapolis                26-27%                   25-32%
  Boston                     28-30%                   33-40%
  Seattle                    69-72%                   43-49%
  Albuquerque                34-39%                   35-43%
  Phoenix                    18-26%                   20-31%
  St. Louis                  18-23%                   20-33%
  Sacramento                 43-48%                   30-39%

(The north orientation is not shown because the impacts of external shading devices are small.)

NOTE: The annual energy performance figures shown here were generated using RESFEN for a typical (new construction) 2000 sq. ft. house with 300 sq. ft. of window area. In the first case, the windows are equally distributed on all four sides of the house. Where windows are predominately on one side, the distribution is 240 sq. ft. on that side and 20 sq. ft. on the others. U- factor and SHGC are for the total window, including frame. RESFEN is a computer program for calculating the annual cooling and heating energy use and costs due to window selection. It is available from Lawrence Berkeley National Laboratory (windows.lbl.gov/software/resfen).

ACKNOWLEDGEMENTS: This report was developed with support from the Professional Awning Manufacturers Association (PAMA). In particular, we appreciate the input from Michelle Sahlin, managing director of PAMA, who initiated and shaped the project. The Windows and Glazings Program at Lawrence Berkeley National Laboratory (LBNL).