Princeton Weekly Bulletin   March 10, 2008, Vol. 97, No. 19   prev   next   current

By the numbers

“Engineering Projects in Community Service”

photograph of Emily Weissinger and Yin Liang measuring a home’s ventilation

From left, junior Emily Weissinger and freshman Yin Liang measure a local home’s ventilation rates as part of an “Engineering Projects in Community Service” course that is focused on helping homeowners optimize energy conservation. (photo: T. Kevin Birch)

Princeton NJ — University students are assisting local homeowners in optimizing energy conservation in their homes as part of a class called “Engineering Projects in Community Service.” The students have partnered with the Stony Brook-Millstone Watershed Association to test homes throughout the area to determine their “ventilation rates” — essentially their level of draftiness — and design “green retrofitting” strategies while preserving adequate ventilation. The course, now in its second year, is administered by the Center for Innovation in Engineering Education.

• This semester, the “Greentrofit team” includes 12 students, ranging from freshmen to seniors, who are majoring in a variety of disciplines, including engineering, philosophy and geosciences. The team is advised by civil and environmental engineering professor Catherine Peters.

• Each ventilation test, lasting two to three hours, is conducted by a pair of students. The team, which began its work in November, is slated to assess 40 homes by early March.

• The students assess ventilation using a blower door test, in which a variable speed fan is fit into the opening of a home’s front door. After closing all exterior doors and windows and opening all interior doors, the fan is used to blow air out of the house. The amount of air flow required to cause the interior pressure to drop indicates how leaky the house is. The students use a thermal imaging camera to document areas of significant leakage.

• The students also analyze each home’s energy bills for the past year. Based on the information gathered, they make recommendations to reduce energy costs while maintaining indoor air quality, such as taking further measures to seal up the house or installing a heat-recovery ventilation system. All homeowners are provided with a report that includes the air exchange rate for their home and the estimated cost of air leakage, along with an explanation of how this compares to U.S. standards for health and energy efficiency.

  • PWB new logo
  • Submit items for future calendars by using the calendar submission form link on the PWB home page.
  • The Bulletin is published weekly during the academic year, except during University breaks and exam weeks, by the Office of Communications. Second class postage paid at Princeton. Postmaster: Send address changes to Princeton Weekly Bulletin, Office of Communications, Princeton University, 22 Chambers St., Suite 201, Princeton, NJ 08542. Permission is given to adapt, reprint or excerpt material from the Bulletin for use in other media.
  • Subscriptions. The Bulletin is distributed free to faculty, staff and students. Others may subscribe to the Bulletin for $30 for the 2007-08 academic year ($18 for current Princeton parents and people over 65). Send a check to Office of Communications, Princeton University, 22 Chambers St., Suite 201, Princeton, NJ 08542.
  • Deadlines. In general, the copy deadline for each issue is the Friday 10 days in advance of the Monday cover date. The deadline for the Bulletin that covers March 24-30 is Friday, Mar. 14. A complete publication schedule is available at pr/ pwb/ deadlines.html; or by calling (609) 258-3601.
  • Managing editor: Eric Quiñones
  • Assistant editor: Jennifer Greenstein Altmann
  • Calendar editor: Shani Hilton
  • Contributing writers: Chad Boutin, Kitta MacPherson, Hilary Parker, Ushma Patel, Ruth Stevens

  • Photographer: Denise Applewhite
  • Design: Maggie Westergaard
  • Web edition: Mahlon Lovett
  • Subscription manager: Elizabeth Patten
  • PU shield