Fume Hood - Behavioral Programs To Reduce Fume Hood Energy Use

Behavioral Programs To Reduce Fume Hood Energy Use

A number of colleges, universities, and other research institutions run or have run programs to encourage lab users to reduce fume hood energy consumption by keeping VAV sashes closed as much as possible. These programs typically use social marketing tactics such as placing stickers or magnets on VAV fume hoods to prompt users to keep them closed, providing feedback to lab users on the amount of energy consumed by fume hoods, and running competitions in which labs compete to see which building or lab can achieve the largest percent reduction in fume hood height or energy consumption. Organizations that have fun energy competitions include:

• Harvard University : A "Shut the sash" campaign in the Chemistry & Chemical Biology (CCB) Department resulted in a sustained ~30 percent reduction in fume hood exhaust rates as a result of increased attentiveness to fume hood sash height. The total pre-campaign exhaust from the 150 VAV fume hoods monitored was 85,000 cubic feet/minute (CFM), and the post-campaign average 59,000 CFM. This translated into cost savings of approximately $180,000 per year, and a greenhouse gas emission reduction of 300 MTCDE (metric tons carbon dioxide equivalent). The campaign included a number of components:
  • Competition: A competition in which labs competed against each other to reduce their fume hood energy use the most
  • Prompts: Placement of “Shut the Sash” magnets on each fume hood as a prompt/reminder
  • Communication: General outreach through posters, flyers, and emails
  • Goal Setting: Monthly goals were set for each lab. These goals were re-evaluated as research groups’ size changes and as their work changes to more or less hood-intensive research.
  • Incentives: Labs that achieved their monthly goal were entered into a monthly raffle in which they could win movie passes or a beer & pizza party. Labs that met their monthly goal at least 4 of the most recent 6 months were invited to highly popular bi-annual wine & cheese parties.
  • Feedback: Real time meters at the exit to most labs allow users to quickly check whether all the hoods are closed each evening if they are the last one to leave the lab. Feedback on performance is distributed twice a month – once to let lab users know if they are on track for their goal, and the other time to let them know who won the raffle that month.

• Massachusetts Institute of Technology:
  • Air volume through all VAV hoods in the department is modulated by a Venturi-type air valve by Phoenix Controls. A nominal face velocity of 100 ft/min is maintained. Data from sash position sensors on each fume hood are sent to a central processor that controls laboratory-scale and building-level exhaust. Software automatically collects and redistributes the 15 minutes average sash position by laboratory from this central database
  • The first fume hood behavior intervention in the MIT Chemistry Department occurred mid-November 2006, when the Chemistry Department’s EHS Coordinator reinforced the importance of closing fume hood sashes at the regularly scheduled EHS laboratory representative meeting. The presentation covered the reasons for shutting the sash (cost savings, benefit to the environment, personal safety), a description of how fume hoods work and how energy is consumed, the dangers of improper fume hood use, and the magnitude of the potential energy savings (up to $400/inch of hood opening per year in the widest hoods in the Chemistry Department (and $80/in/year for the hoods in Building 18). Representatives were encouraged to respond after the presentation and after discussion with their labs. This message was reinforced by an e-mail from the department head to the faculty with the goal of ensuring the entire department was familiar with the program. The “shut-the-sash” message was subsequently integrated into the Chemistry Department’s EHS training sessions that are required for all new graduate students.
  • The second intervention was the release of fume hood use data to the faculty principal investigator in charge of each lab. The first datasets were distributed by the department EHS coordinator to the Chemistry faculty in early August 2007. These data were then distributed to other members of the lab at the faculty PI’s discretion.
  • Findings: Average sash height was lowered by 26 percent (from 16.3 +- 0.85 percent open to 12.1 +- 0.39 percent open) throughout the department, saving an estimated $41,000/year. Sash position during inactive periods was lowered from 9 to 6 percent open. Half of all department savings occurred in four (of 25) labs. Energy savings are substantially less than original expectations because most installed fume hoods use combination sashes. Labs with vertical sashes use the most energy, and see the most savings from the intervention.

• North Carolina State University - During sash closing campaigns conducted at the beginning of each semester, Energy Management and Environmental Health and Safety conduct campus presentations highlighting the University’s responsibility to conserve energy and provide safe working conditions with the goal of educating scientists and research assistants on proper lab protocol and ways to reduce their carbon footprints. Sash opening labels have been placed on all fume hoods on campus to serve as constant reminders for all lab users. In addition to these campaigns, periodic surveys are conducted to inventory which labs are practicing correct lab safety procedures. These surveys also highlight buildings with high energy consumption where further monitoring or outreach is needed.

• University of British Columbia UBC held their first fume hood competition in 2012. Over the course of the six weeks competition, an 85 per cent reduction in fume hood energy consumption was achieved. Six labs were recognized for exemplary fume hood practices at a wrap-up event attended by 130 researchers, with first place groups receiving $500 and second place groups receiving $250. All winning groups also received a commemorative sash (pun intended).

• University of California, Berkeley UC Berkeley's “Shut the Sash” Fume Hood Campaign educates lab researchers to close the sashes on fume hoods when they are not in use to reduce energy consumption and improve air quality. As of May 2011, the program targets Tan Hall and uses stickers, flyers, and emails to disseminate information. It also involves a competition to see which lab can “Shut the Sash” most consistently.

• University of California, Davis: In summer 2009, about 600 vinyl were installed on the exterior sidewall of fume hoods in ten buildings at UC Davis. The sticker uses a traffic light color scheme, with a red zone above 18 inches, and a large arrow pointing down with the words, “More Safe, Less Energy” changing from yellow at the midpoint to green at the bottom when the sash is closed completely. Visual surveys of sash-position status were conducted before sticker deployment, about 2 months after sticker installations, and again in spring, 2011, to assess persistence. The survey method estimated sash status by benchmarks in approximate quartiles to streamline the survey effort. This also helped capture information on VAV-system response. These benchmarks were incorporated into energy savings calculations. Sash positions were averaged by floors at each sample time. Survey results showed 90-100% compliance 22 months after installation with no additional reinforcement of closure. Given a per hood sticker installation cost of $5 and a conditioned air cost of $7/CFM/year, the simple payback of the project was estimated to be 15 hours, and the return on investment (ROI) was estimated to be 599%.

• University of California, Irvine : In order to get the fume hoods sashes closed, UC Irvine's Green Campus Program uses a three-pronged approach. The first method is direct education, in which teaching assistants (TAs) are asked to encourage their students to close the hoods before leaving the labs. The second approach is placing “point-of-decision” reminder stickers on the hoods themselves, explaining that a closed fume hood saves up to 50,000 lbs of CO2 a year. The third method is an incentive-based competition among three buildings that contain fume hoods. During the three week competition, volunteers periodically audit the buildings’ fume hoods, noting the total number of inches each fume hood has been left open. The building with the fewest total number of inches at the end of the competition wins a catered luncheon for its professors and lab users, and an energy-efficiency certificate provided by the Green Campus Program. In 2007, the Fume Hood Use campaign won an award for “Best Practices in Student Energy Efficiency,” at the sixth annual Sustainability Conference at UC-Santa Barbara, beating all other Green Campus Programs in the UC system. The campus' Green Campus club estimates that the Fume Hood Use campaign saves over 80,000 lbs of CO2 and $13,000 every quarter.

• University of California, Los Angles : As its first initiative, UCLA EH&S's Laboratory Energy Efficiency Program (LEEP) sponsored a competition to encourage reduced fume hood sash heights in research laboratories. The first fume hood competition took place in the Molecular Sciences Building (MSB) during Fall 2008 and included about 230 fume hoods. Overall, the competition saw a 40% sash height decrease from 13.4” to 8” (as shown by competition behavior and the long-term followup). In order to identify the lasting, long-term behavior change, LEEP conducted follow-up audits each month after the competition. Sash heights were measured throughout one week, using the same method for recording baseline measurements. The follow-up data showed that MSB’s new average sash height was 7.8”—a 5.6” decrease from baseline measurements. Ultimately, this 40% reduction translates into an annual estimated savings of 1,415,278 lbs of CO2 emissions and $149,730. Several additional competitions have been held following the success of this original one.

• University of California, Riverside : Make posters & stickers available for download on their website.

• University of California, San Diego: The UC San Diego Annual Shut the Sash Competition is a 5-week campaign sponsored by the Green Campus Program, Facilities Management, Environmental Health & Safety, and the Biology Department. The first competition began in January 2009 and, as of October 2012, has happened every year since. The campaign involves 11 labs in a challenge to reduce their energy consumption and improve air quality by closing the sashes on fume hoods when not in use. The “Shut the Sash” competition helps promote energy savings by challenging laboratories to save more energy than other laboratories from a set baseline. The Shut the Sash Competition educated researchers, raised awareness of lab energy efficiency and showed real savings in energy use and cost. On average, there was a 27 percent reduction in sash heights over a five-week period in 2009. The Shut the Sash competition and awareness campaign also saves 21,734 kWh/year or $1695.25 annually, assuming sash heights stay at a similar level.

• University of California, Santa Barbara: In summer 2009, about 200 vinyl were installed on the exterior sidewall of fume hoods in seven buildings at UC Santa Barbara. The sticker uses a traffic light color scheme, with a red zone above 18 inches, and a large arrow pointing down with the words, “More Safe, Less Energy” changing from yellow at the midpoint to green at the bottom when the sash is closed completely. Surveys were conducted by collecting real-time sash position data provided by the campus’ building monitoring system (BMS). Data were collected for 10-day periods prior to sticker installation for select fume hoods, and one, two, and three months following sticker installation. The average sash height for each hood was calculated for each 10-day period. In the Engineering Science Building, average sash opening was ~15 inches prior to sticker installation, ~6.5 inches 3 months after sticker installation, and ~9.5 inches 23 months after sticker installation. In the California NansoSystems Institute building, average sash opening was ~7.5 inches prior to sticker installation, ~6 inches 3 months after sticker installation, and ~5 inches 23 months after sticker installation.

• University of Central Florida: Have placed reminder stickers on fume hoods.

• University of Colorado, Boulder: Using stickers and educational posters to reminder users of VAV fume hoods to keep them closed

• University of Toronto The University of Toronto ran their first fume hood sash closing campaign from October 2008 until March 2009. The campaign included workshops, posters, a website, and individual and group competitions. Before the campaign, sashes were regularly left in the same position whether the hoods were in use or not (around 11 inches). During the campaign, sash heights of unused hoods dropped to just under 4 inches on average, resulting in estimated annual savings of at least 49,000 kWh of electricity, 770 mmBTU of heating energy and 51 tonnes of greenhouse gases and as much as 240,000 kWh, 3800 mmBTU of heating energy and 260 tonnes of greenhouse gases. The changes also resulted in between $20,000 and $100,000 in energy cost savings annually. When the campaign organizers inspected sash heights 7 months after the conclusion of the campaign, they found that users had largely reverted to pre-campaign habits.