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The implementation of energy efficiency measures at wellesley college, focusing on the use of different types of light bulbs and their impact on energy costs. The authors suggest a combination of policy and behavioral changes to reduce electricity consumption and costs, using cfls, leds, and other lighting options. The document also discusses the experiences of other institutions and provides a bibliography for further reading.
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Econ 228, Spring Semester
Keaty Gross Lauren Nelson Lauren Rasmussen
Summary: To reduce lighting costs on campus either light usage or wattage must be decreased. Many options exist that fulfill both of these criteria including light timers, motion detectors, capitalization of natural light, light dimmers, switching light bulb types, and purchasing bulbs with lower wattage. The most beneficial option, switching incandescent bulbs to compact fluorescent light bulbs, would accrue no additional labor costs and cut energy costs by 80 percent. These bulbs are available in both the standard Edison base and the Candelabra base, making them usable in almost all lamps currently using incandescent lights. Not only do CFLs use less energy but the bulbs often cost less than incandescents. Although students have presented their findings on this issue to the distribution manager and power plant employees, the college still purchases and uses incandescent bulbs. In order to significantly reduce energy costs, the college needs to work with students, faculty and staff, to institute a standardized plan and policy across campus. This policy would involve phasing out incandescent bulbs by stopping their purchase. The current stock of incandescent bulbs should be reserved for buildings where incandescent light color is preferred, such as Jewett. In the future, replacement bulbs should be fluorescent, metal halide, halogen or LED. Information on these bulbs should be included in the annual custodian training session, covering their ideal placement and disposal policy. Freshmen orientation should include a session on electricity reduction methods such as turning off lights when not in use and installing fluorescent bulbs in personal lamps. In addition, first years should direct energy reduction campaigns within their residence halls in lieu of the old Bell’s Duty. With a combination of policy and behavioral change, Wellesley College could reduce electricity costs by $33,891 in one year by simply using CFLs instead of incandescent bulbs.
Introduction : Commercial institutions such as Wellesley College typically attribute twenty to thirty percent of their energy expenses to campus lighting. A reduction of this portion of Wellesley’s energy bill would prove beneficial to the environment and potentially save Wellesley thousands of dollars per year. There are many means by which the college could achieve this goal.
produce more heat than light, thereby wasting a huge amount of energy. Their main benefits are their low price and availability. Yet, while these bulbs have a low initial cost, they eventually incur high costs through higher energy use and frequent of replacement. Halogen bulbs provide high quality light and withstand sub-zero temperatures. They are ideal for use outdoors and in large, open spaces such as hallways or auditoriums. Many halogen bulbs fit standard Edison sockets. They also last twice as long as the incandescent bulb and reduce energy consumption by ¼. However, these bulbs are more expensive then incandescent bulbs and cost approximately four dollars each. Installation of additional haloge n lights would incur a high initial cost but save money in the long run by reducing energy consumption. Light-Emitting Diodes (LED lighting) , are highly praised for energy efficiency and provide an excellent option for exit sign lights. Three LED light bulbs can run on only 0.22 watts, a number significantly lower than any other option. There are some drawbacks to LEDs, including light quality and installation price. Because they provide no more than 17 lumens per watt, the quality of the light is poor and quantity of light produced could never fully light a room. LED bulbs are also smaller than regular bulbs and would require new lighting fixtures. The best application of LED technology is the permanent illumination of exit signs or emergency pathways. The cost of installing these bulbs in all exit signs is negligible when compared to the expense of retaining incandescent signs. Metal halide lamps contain mercury, sodium/scandium iodide, halogens and sometimes metals in the rare earth group of the periodic table. In general, metal halide lamps yield a more attractive light than high pressure sodium lamps and have higher luminosity than high pressure mercury lamps. They are less affected by change in ambient temperature than fluorescent bulbs, making them ideal for large or open-air areas such as gymnasiums and stadiums. Their primary drawback is their tendency to explode at the end of life, an issue addressed by either a glass shroud around the arc tube or a Teflon coating on the outer jacket. They cost about $90 per bulb and $115 for the ballast and are currently used in all free-standing lamp posts on campus. Compact fluorescent lighting (CFL) would be ideal for residential halls on campus. CFLs live ten times as long as incandescent bulbs and consume one–fifth the
energy. The college would not have to install new light fixtures to accommodate CFLs because they have the same Edison base as incandescent bulbs. A 23 watt fluorescent bulb costs the college $0.75, a slightly higher price than the equivalent 90 watt incandescent bulb. The college provides these bulbs to students free of charge, but ultimately saves thousands of dollars in energy costs. A drawback is that the light quality is not as high as incandescent bulbs and halogen bulbs, with 48-60 lumens per watt. Standard Fluorescent lights (SFL) emit high quality light, ideal for classrooms and offices. This option is considered the most efficient lighting option, providing 60- lumens/watt. These lights are widely available and fit the standard light socket. The light itself can appear bluish and is generally not appropriate for living areas. SFLs also flicker frequently, causing additional irritation. They are best used in offices and classrooms that do not have enough windows to provide sufficient natural light. Fluorescent floodlights are now available, providing yet another alternative to incandescent floodlights in corridors. When determining which options will work best on our campus, Wellesley’s Sustainability Advisory Committee should keep in mind that these adjustments not only reduce energy use and therefore have positive effects on the environment, but also would save the college a significant amount of money. In summary, Wellesley College should install LED lights for all exit signs, CFLs for dorm rooms and small offices, halogen or fluorescent flood lights for some academic and dorm corridors, halide for outdoor use and a combination of CFLs, SFLs and natural light for classrooms and the majority of the offices. By changing the type of light and the amount of time the lights are on, the college could save a great deal of money while reducing environmental impact.
Analysis of implementation of the project at other location(s ): Similar institutions: In 2004, an Environmental Studies seminar at Mount Holyoke College established a “Campus Energy Initiative” to raise awareness of energy conservation issues across campuses nationwide. Their goal was to inform and motivate students with their research and “achieve a more sustainable campus by promoting environmental responsibility, conservation of resources, energy efficiency, and increased reliance on renewable energy
Chesapeake Bay Foundation The Chesapeake Bay Foundation is an environmental organization with the objective to protect and restore the Chesapeake Bay and its tributary rivers by improving water quality and decreasing pollution in the area. Their headquarters, the Philip Merrill Environmental Center, is considered the world’s “greenest” building and received the U.S. Green Building Council’s first Platinum rating for Leadership in Energy and Environmental Design (LEED). The building utilizes natural ventilation, passive solar heating and cooling, daylighting, use of recycled and recyclable building materials and relies on renewable energy sources. One-third of all the building’s energy comes from renewable energy sources. The use of daylighting in the Philip Merrill Environmental Center has drastically reduced total energy costs. The lights in the building are programmed in conjunction with natural sunlight so that as the amount of sunlight entering the building increases, the lights dim thereby reducing energy consumption. Similarly, when clouds roll in or as it gets later in the day, the lights increase so that there is a constant level of light in the building, from variable sources. This technology has reduced energy costs immensely. Areas of the building that don’t get sunlight are monitored with motion detectors that using infrared radiation. Because the lights automatically turn on and off when people enter and exit, energy is no longer wasted by people forgetting to turn off lights. The Philip Merrill Environmental Center has achieved a tremendous accomplishment that we, as Wellesley students, can apply to our own projects here on campus.
Implementation of the project at Wellesley College : At Wellesley College we have a combination of incandescent, fluorescent, halogen, LED and metal halide bulbs used across campus. In many locations, multiple types of bulbs are used in the same types of fixtures. The college supplies CFLs for students and faculty to encourage their use and save the college money by reducing energy consumption. The faculty may attain fluorescent bulbs for office lamps through either the custodial staff or stocks in department offices. In residence ha lls, fluorescent light bulbs are available in all kitchens
and at the “Bells Desk” free of charge. Despite these efforts, the college falls short in several aspects of policy implementation. Once these light bulbs run out, it takes almost a week for the supply to be restocked, increasing the likelihood that students will buy their own bulbs, generally opting for the cheaper incandescent bulbs. Also, despite the trace amounts of mercury in the fluorescent bulbs, no recycling facilities are available for these bulbs in any of the residence halls. Exit signs across campus vary between LED lights and incandescent bulbs. Exit signs, lit twenty-four hours a day, seven days a week use mass amounts of energy when incandescent bulbs are used. When continuously us ed, incandescent bulbs last approximately one month before burning out, while LED bulbs are estimated to last for twenty years. Although some incandescents are still used in older models of exit signs, all of the newer models use LED bulbs. The next step would be to replace the old exit signs with new LED signs, which would dramatically decrease their energy consumption. Halogen lights, although not as ideal as fluorescent bulbs, are widely used across campus for hallways and auditoriums, while standard fluorescent bulbs and metal halide bulbs are used in large lighting areas. However in some hallways and auditoriums, the less efficient incandescent lights are still used. In fact, all lights in the Jewett Auditorium are incandescent rather than halogen or fluorescent. Throughout hallways in Pendleton the incandescent bulbs are installed randomly, without a standard placement. However, metal halide bulbs are used uniformly in the lamp posts throughout campus because they are ideal for large open spaces that need high wattage. Wellesley College has utilized new technologies such as dimmable and “green” fluorescent bulbs in refurbished buildings and corridors. The new light fixtures in the humanities corridor in Green Hall have all the benefits of fluorescent technology without the unpleasant blue-tinge, flickering and hum generally associated with fluorescents. These lights are installed in all of the new offices in this corridor and provide different shades of light to suit the individual comfort level of the employee. Wellesley College recently received a generous donation from Leonie Faroll, Class of 1943, of 27 million dollars towards capital improvements to the power plant, infrastructure improvements, structural renovations, and new equipment in the Science Center. This money funded the installation of electric meters in all buildings on campus
bulb. If bulbs are exchanged through standard burnout-replacement-procedures, then there will be no additional labor costs. Disposal of fluorescent bulbs presents the college with additional costs. As a large commercial user of tubular fluorescent lamps, Wellesley College is required by law to recycle or properly dispose of bulbs due to their trace mercury content. Since Wellesley currently uses standard fluorescents across campus, a system is already in place to deal with the disposal of fluorescent bulbs. Hazardous waste is also collected once at year at the Wellesley Recycling and Disposal Facility HHW Drop-Off Site. Our custodial staff is trained in Wellesley’s disposal protocol, making the transition to CFLs rather seamless where disposal is concerned. Even though the number of bulbs requiring disposal every year will increase, there are no additional implementation costs of labor, startup or training. Environmental concerns obviously extend beyond the college campus and therefore the college must consider any social costs or benefits of a policy change. The risk of mercury contamination by the fluorescent bulbs is the primary societal cost of implementing the project. When products containing mercury are broken, disposed of improperly or incinerated, the costs of contamination can be extreme:
Mercury is … a nerve toxin that can impair the way we see, hear, walk and talk. Mercury released from broken devices can vaporize, contaminate the air in our homes, and sometimes go down the drain. Mercury vapor eventually reaches the atmosphere. From there, mercury can mix with rain and snow and fall into lakes and waterways were it can mix with bacteria and be converted into methyl mercury. Methyl mercury contaminates the food chain and builds up in the tissue of fish and of wildlife and humans who eat the fish. 1
Ironically, switching to fluorescent light sources may actually decrease the amount of mercury released into the atmosphere.
The highest source of mercury in our air comes from burning fossil fuels such as coal, the most common fuel used in the U.S. to produce electricity. A CFL uses 75% less energy than an incandescent light bulb and lasts at least 6 times longer. A power plant will emit 10mg of mercury to produce the electricity to run an incandescent bulb compared to only 2.4mg of
(^1) http://www.earth911.org
mercury to run a CFL for the same time. – EPA FACT SHEET: Mercury in Compact Fluorescent Lamps (CFLs).^2
In other words, our proposal will not cause additional harm to the environment. By decreasing the amount of fuel burned on campus we also decrease our net amount of mercury pollution. The college will benefit by purchasing fewer bulbs and using less energy. Wellesley College purchased 10, 943 incandescent bulbs in 2002, an increase from the 9,822 incandescent bulbs purchased in 2001. In 2002 alone, the college could have saved roughly $33,891 on electricity^3. Every CFL bulb purchased would also save the college $5.15 in purchasing costs, since a single CFL replaces ten fluorescent bulbs.^4 Ultimately, the college saves between 23 to 59 dollars on every fluorescent used in lieu of an incandescent. In most cases the number is closer to 59 dollars because higher wattages are used most frequently. The cost of an incandescent or fluorescent bulb can be determined with a simple formula. To obtain a numerical cost-benefit comparison of standard incandescent bulbs and CFLs, the bulb wattage per hours used is multiplied by the cost of electricity per kilowatt hour. Because wattage and lifetime vary considerably, both the high and low ends of the spectrum are included in this cost-benefit analysis. Hours of usage were determined by the CFL lifetime. After calculating the cost of electricity for each bulb, the cost of the bulb itself was added. The price is multiplied by the ratio of incandescent and fluorescent lifetimes, generally approximated as 10:1.
Low wattage, short lifetime (40 watt) x (8,000 hours) x ($0.07 / 1 kWh) = $ 22.40 + (10 bulbs x $0.44) = $ 26. (7 watt) x (8,000 hours) x ($0.07 / 1 kWh) = $ 3.92 + (1 bulb x $0.34) = $ 4.
(^2) http://www.earth911.org (^3) ES 300. Audit of Wellesley College's Greenhouse Gas Emissions. (^4) Bob Bossange. Interview.
fluorescent bulbs less toxic, more appealing the eye, and able to fit in the standard socket, the costs students incur from using fluorescents are practically eliminated. Students benefit from the use of fluorescents because the bulbs are supplied by the college free of charge. The change from incandescent to fluorescent has no real effect on the faculty since the college provides the bulbs. All new offices are equipped with dimmable fluorescent lights, an item that allows faculty to choose the optimal color and amount of light in their offices. There are no disadvantages to these new technologies, and the maintenance staff will have to change light bulbs ten times less than when incandescent bulbs are used.
Major obstacles to implementation at Wellesley: In the past, an obstacle to change has been that disinterested parties who do not pay for the electricity (i.e. contractors and custodians) install and replace the lights. Without an official policy change, they have no incentive to deviate from routine. However, if the light bulbs made available to Wellesley custodial services are only “green” CFLs there should be no impediment to the change. A few light fixtures in academic buildings must remain incandescent due to aesthetic considerations, such as the dual bulb chandeliers in the newly designed humanities wing of Green Hall. However, these bulbs have an E12 candelabra base instead of a standard Edison base and therefore there should be no confusion about where the few incandescent bulbs still purchased should be placed. A more future oriented policy should include provisions for prospective construction. The modern fluorescent technology implemented in the remodeled humanities corridor should be the model for future construction sites at Wellesley College, in that old lighting systems should be replaced by the dimmable fluorescent technology.
Decision-maker for implementation of the project: The primary people to discuss such an action with are Peter Zuraw and Robert S. Bossange. Mr. Zuraw is the assistant vice-president and director of the physical plant. He is dedicated to environmental reform within the Wellesley community and has met with various student body leaders to discuss campaigns for a more energy efficient campus. He would be the one implementing the official policy. Mr. Bob Bossange is the
Director of Auxiliary Services in the Purchasing Department of the Distribution Center. He is responsible for ordering campus light bulbs. The college may also have to speak with department heads, especially the art department, regarding the replacement of all incandescent bulbs once they burn out.
Conclusion: Energy consumption can be decreased significantly with a few simple behavioral changes. Implementing a poster campaign and dorm competitions, creating a committee to resolve additional energy concerns, and integrating energy consumption education into first year orientation and dorm meetings are a few effective ways to reduce energy consumption on campus. In addition to these changes, there are many policy changes that could further decrease electricity consumption. The college should completely discontinue the use of incandescent bulbs and replace them with more efficient, cost effective fluorescent bulbs. Wellesley should also install timers and motion detectors in appropriate places such as bathrooms, offices, labs, and certain outdoor lighting systems. Also, by having the administration reinstate the underclassmen community service policy, we can easily create a program to recycle light bulbs and establish a foundation for a campaign committee on energy efficiency. If underclasswomen were required to provide these services to the college, campus awareness on the issue would be widespread and students take more responsibility for their environment. If properly implemented, these behavioral and policy changes will tremendously decrease energy consumption on campus.
International District Energy Association, “Cooling, Heating, and Power in the Nation’s Colleges and Universities,” International District Energy Association, http://www.eere.energy.gov/de/pdfs/chp_idea_survey.pdf Mount Holyoke, “Campus Energy Initiative,” Mount Holyoke College, http://www.mtholyoke.edu/courses/jbubier/es390second%20copy/index.htm Natural Resources Defense Council, “How to reduce your energy consumption: Tips for conserving electricity and cutting your energy costs,” Natural Resources Defense Council, http://www.nrdc.org/air/energy/genergy.asp Other power, “Efficient Lighting,” Forcefield, http://www.otherpower.com/otherpower_lighting.html Parabon Computation, “You have a precious resource,” Parabon Computation, http://www.parabon.com/providers/index.jsp#energy Philip Merrill Environmental Center, “Bay Conservation at Work,” Chesapeake Bay Foundation, http://www.cbf.org/site/PageServer?pagename=about_merrillcenter_index Service Lighting, “Service Lighting: Now light- years ahead,” Service Lighting, http://www.servicelighting.com/ Stanford University, “Light Efficiency,” Stanford University, http://ise.stanford.edu/class/psych221/projects/02/raytseng/8aeff.htm Wellesley ES 300, “Audit of Wellesley College’s Greenhouse Gas Emissions,” Wellesley College, http://cs.wellesley.edu/~weed/papers/GHG-Assessment-spring-2003.pdf Wellesley Town Hall, “Wellesley, Massachusetts,” Town of Wellesley, http://www.ci.wellesley.ma.us/Pages/index Wellesley Web, “Wellesley Web,” Information Engineer.com, http://www.wellesleyweb.com/wwhomep.htm Wikipedia: the free encyclopedia, “Incandescent Light Bulb,” Wikipedia, http://en.wikipedia.org/wiki/Incandescent_light_bulb World Resources Institute, “Earth Trends: Environmental Information,” WRI, http://earthtrends.wri.org/#
Table 1:
Bulb Base Wattage Voltage
Lifetime (hrs) Lumens $/unit Incandescent A19 Edison
15 to 135
120 to 277 500 - 2,000 100 - 2,
$0.44 or $0. Incandescent B10 Candelabra 25 to 60
120 or 130 1,500 - 3,000 850 $2. Incandescent BR30 Edison 75 130 2,000 850 $5. Fluorescent E (CFL) Edison 8 to 25
110 or 220
8,000 - 10,000 600 - 1,
$0.34 or $0. Fluorescent E (ref) Edison^23
110 - 230 12,000^ 250 - 1,200^ $22. Metal Halide (ED-37) E39 Mogul 400 N/A 20,000 28,800 $20. Flood Halogen (ref) Edison 50 120 2,
1,350 - 4,500 $8.
Table 2: Jewett Founders Incandescent 358 64 CFLs & Halogens 168 180
Figure 1:
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Jewett Founders facilities
Distribution of Incandescent, CFL and Fluorescent Bulbs in Academic Facilities
CFLs & Halogens Incandescent
