Efficient Lighting Upgrades - Campuswide
With thousands of fixtures across campus, keeping up with improved lighting efficiency is a continuous process. In the past year, we have upgraded many fixtures and lamps to the best available fluorescent and LED technologies. Lighting efficiency upgrades have been completed in Blunt Alumni Center, and Kemeny/Haldeman, while work is underway in Collis Center, McNutt , Parkhurst, Hanover Inn, Cummings Hall, and Dartmouth Hall. We have utilized student interns to help determine where lighting upgrade opportunities exist and have joined with National Grid and are receiving energy rebate payments for portions of the work. We have had good success in employing LED lighting technology in spaces where lighting is active for long periods of time. This multi-faceted lighting upgrade program will continue to be expanded with an attempt to complete all campus buildings by the end of 2010.
Occupancy Sensors - Campuswide
Lighting in common areas, lounges, and hallways is often left on when not needed. We are installing occupancy sensors in many of these spaces to reduce excess energy use when no one is using these spaces. We have joined with National Grid and are receiving energy rebate payments for portions of the work. The program will continue to be expanded with an attempt to complete all campus buildings by the end of 2010.
Daylighting Controls - Campuswide
We have identified a number of locations around campus where lighting may be cut back or shut off by controls when natural lighting levels exceed those of artificial lighting. A few examples include corridors, exhibit areas and perimeter study areas in Baker/Berry Library, the central atrium in Collis Student Center, and corridors in Kemeny/Haldeman.
Lighting Upgrades - West Gym
The large lighting systems in our sports venues were designed at a time when energy was far less expensive than today. They are not very capable of being switched to lower lighting levels or being shut off when portions of the spaces are vacant. As a result, much of the lighting is left on during large portions of the day and evening. We are piloting a project in the West Gym to replace these fixtures with fluorescent sources which will provide multiple levels of lighting and flexible zoning for different activities. We will provide a touch-screen display that will allow users to make smart choices in their selection of lighting levels and areas or use. We will also provide vacancy sensors to ensure that lights are switched of if users forget to make the "smart choice" of turning off the lights when they leave. If this proves successful we plan to employ this technology in Leverone Field House, Leede Arena, Boss Tennis, and Thompson Arena.
Chiller Replacements
Dartmouth Medical School replaced its two 315 ton, steam absorption chillers with two new 500 ton electric drive centrifugal chillers. They also replaced the component parts including the pumps used to move chilled water around the building, the cooling tower, and the system controls. The new chillers have a much higher operating efficiency than the old units. Even though chilling capacity increaed from 630 tons to 1000 tons, the new chillers will produce an energy savings of approximately $250,000/year and reduce the burning of fuel oil at the central heating plant with a net overall reduction in greenhouse gas emissions. Dartmouth is considering other absorption chiller replacements across campus for efficiency improvements and additional greenhouse gas reductions.
Fume Hood Controls
The control systems for fume hoods in several laboratories on campus are being improved to provide greater flexibility and reduce energy use. Upgrades have been completed for teaching labs in Steele Hall allowing significant reductions in airflow through the lab spaces during periods when classes are not in session (nights, weekends and semester breaks). Other lab spaces in Steele Hall, Burke Chemistry Lab and Cummings Hall will be surveyed in 2009 for application of other energy efficient ventilation control techniques.
Heat Recovery
Several of our larger science facilities utilize large quantities of conditioned outdoor air for ventilation of laboratory spaces. Burke Chemistry Lab and Vail Hall at the Medical School are two of the largest examples. Both of these buildings utilize 100% outdoor air, which is heated or cooled to space comfort conditions depending upon the season, introduced to the laboratories, and then exhausted through the fume hoods to the outdoors. There are no heat recovery systems in these buildings. We are working with these departments and developing plans collect the exhaust air and run it through heat recovery coils to capture the waste heat (or cooling) and reintroduce the energy to the incoming air stream. We are working hard to develop implementation schemes that will result in the least impact to research operations, while producing the most efficient and cost-effective heat recovery. These system are large and technically challenging, yet represent some of the greatest savings potentials on campus.
Steam Trap Maintenance Program
Dartmouth has an extensive network of steam distribution piping across the campus. Much of it is in manholes, steam tunnels, and mechanical equipment rooms. In addition to steam and condensate piping, there are greater than 2,000 steam traps that keep steam in the system while allowing condensate to be efficiently returned to the Heating Plant to be reconverted to steam. During December of 2008, a complete survey of our campus steam trap network was performed. We received a good grade with only a 6% "failed open" rate reported. Nonetheless, this amounts to over $250,000 in energy waste per year. We are systematically repairing each of the steam traps identified in the survey as "failed". We have also set up a formal steam trap testing program, with trained in-house staff dedicated to testing, recording and repair of the steam system. This program will continue indefinitely and is certain to return a great operating savings each year.
Glazing Systems
Several of our buildings have large expanses of single glazed windows. They include the Hopkins Center, Vail Hall, Dana Biomedical Library, and others. While expensive to upgrade, retrofit of these existing systems with new double or triple glazed units will provide significant energy savings and greenhouse gas reductions. We are working with the departments in these buildings to develop schemes that would allow us to retrofit the glazing systems while introducing the least disruption to programming of the spaces.
Water Heaters
Our Energy Audit identified several buildings with old storage type domestic water heating systems. These systems are inefficient and will be replaced with semi-instantaneous type water heaters starting with the Hopkins Center. We also plan on replacing storage type systems in Alumni Gym, and Thompson Arena.
Tap Water Options
Dartmouth has hundreds of water coolers across campus consuming energy 24 hours a day. The Hanover Water Company completed a major upgrade to its water filtration system in 2007, vastly improving the taste and quality of water. With these changes in place, we are developing options to bring back the tap. We are encouraging use of simple and inexpensive options, like Brita pitchers and point of use systems across campus. We will also plan on piloting several hydration stations in high-use areas to encourage the switch from bottled water to tap water.
Energy Meters
Dartmouth is fortunate to have an extensive utility metering system throughout the campus. There are approximately 250 steam, electric, and chilled water meters that record utility use in each of the buildings. The meters are read manually each month for billing purposes. During 2008 the entire metering network was surveyed and repairs were made to many meters. The meters now provide an accurate monthly view of our energy use for each building although they must still be read manually. Automating our meters will help us detect and track down unusual energy use patterns and allow us to quickly respond to wasteful system operations. We have tested wireless data transmission technology and plan to use it to help automate our metering systems.
Campus Energy and Sustainability Management System
We are finalizing plans to implement a web-based Campus Energy Management system for the entire campus. The system will connect to building energy control systems and will receive real-time-energy information from the newly automated metering systems. The Campus Energy Management system will allow facilities managers to track energy use in near-real-time, receive live weather forecast data, compare projections to actual use, and detect issues of waste and inefficiency. The system will also allow multiple stakeholders around the campus community to view and utilize this energy data. We anticipate reductions in energy use patterns by building occupants as this information is displayed and fed back via displays around campus and through the campus web-site. We are excited to implement this new system which has been shown to reduce energy in other campus settings from 5% to 15%. The new system will improve our operations, save energy, reduce greenhouse gas emissions, and allow us to communicate energy use patterns more effectively to the entire campus community.
Photovoltaic Panels - Cummings Hall
20 photovoltaic panels were installed on Cummings Hall at the Thayer School of Engineering in 1995. The 20-panel system was installed as a demonstration project for engineering students and produces approximately 5,000 kWH of electricity annually. Instrumentation for the project has recently been rejuvenated.
Ground Source Heat Pump - Fahey-McLane
Dartmouth installed ground-source heat pump systems for the Fahey-McLane dormitory complex. The dorm is a LEED Gold certified building constructed in 2006. The ground-source heat pump systems provide 100% of the cooling and a portion of the heating for the dorm.
Solar Thermal Boiler Water Preheating - Heating Plant
We are considering installation of solar thermal panels on the roof of the Heating Plant to preheat the city water that is used as makeup for the boilers. A series of mounting plates were installed for solar panels during a recently completed roofing project at the Heating Plant making for a fairly simple solar panel installation.
Other projects under consideration:
Solar Thermal Domestic Water Heating - new Class of1978 Life Science Building
Solar Thermal Water Heating for College Heating Plant - new Visual Arts Center
