- Green Lights
The green lights program, driven by the U-M Office of Campus Sustainability’s Energy Management team, aims to save energy and money by replacing current light fixture lamps with more energy efficient lamps. This program was developed in 2015 to replace existing 32-watt fluorescent lamps with 25-watt lamps.
These new lamps yield a 22 percent savings over the older lamps and they will last longer thus reducing cost and waste.
This program is currently underway in several buildings on campus with the end goal of replacing light fixture lamps in over 100 buildings.
Energy savings from this program support the University’s goal to reduce greenhouse gas emissions by 25 percent by 2025.
This program has been completed in the following buildings:
- Lab Hibernation Program
Lab facilities have long been a focus due to their high energy use per square foot. Labs are energy-intensive because conditioned air is sent into the space and exhausted through the fume hoods as “once-through." The air is not recirculated for safety reasons. When there are changes in research or researchers, lab spaces and fume hoods are unused for long periods of time, yet the air exchanges continue as if it were a fully functional lab. Therefore, Energy Management developed the Lab Hibernation program to prevent this energy waste. The program safely and quickly puts unused lab space and fume hoods into a hibernation state, which lowers the air exchanges in the lab. The program has hibernated 21 hoods so far, saving $8,000 in just a few months.
- Occupancy sensing technology in BSRB
It was noted by occupants and the Energy Management Team that lights were lit and ventilation was active during unoccupied times. The recommendation was to install occupancy sensors in the ribbon area offices to control lighting and HVAC off during unoccupied times. In addition, the ribbon area office fans schedule was modified to turn off during night hours. Also, new lighting and HVAC upgrades reduced the overall utility usage. The estimated savings are $113,100/yr.
- Fan scheduling at School of Dentistry
The School of Dentistry has 11 major air handling units that provide heating, cooling and fresh air to its nearly 380,000 square feet of building space. In the spring of 2011, the Energy Management Team reviewed the fan schedules with the facility manager and identified many opportunities to trim back the fan schedules throughout the complex in order to save energy. Many air handling units were running late into the night and on the weekends. After trimming the schedules and fine-tuning them over the first year, the School of Dentistry has avoided over $200,000 annually (or 19% based on FY2013 utility costs) in utility costs because of these changes.
- Lab Sensors in Atrium Labs – Chemistry Building
The HVAC system in all atrium level teaching laboratories in the Chemistry Building were recently renovated to include Phoenix controls on the exhaust airflow side and a manual HVAC turndown switch. The installation of a HVAC turndown switch was agreed upon by the Chemistry facility staff; Environment, Health and Safety (EHS); and the Building Engineering Team. Upon installation there was a training program implemented to ensure proper operation of the system. However, over time the operation of the HVAC turndown switch has been decreasing. During the initial walkthroughs, only 50% compliance from the laboratory users was noted, leaving several laboratories unnecessarily operating in unoccupied conditions.
ECM recommendation: All parties agreed to convert this system from a manual switchover to an occupancy sensor driven switchover providing the laboratory air change rates are maintained at 10 ACH during unoccupied periods, and the training program for graduate student instructors is maintained. Under this project the 14 atrium level teaching labs were outfitted with dual-technology occupancy sensors to toggle the HVAC system and lighting between the minimum and maximum settings. These changes will result in significant energy savings (motor horsepower, heating, and cooling systems)
- Lighting in Rackham
Lights (chandeliers and wall sconces) in reading rooms were turned on daily at 6:00am and off at 11:00pm to make stately reading rooms warm and inviting. Some were on 24/7, but the rooms were seldom occupied for extended lengths of time. Occupancy and daylight sensors were installed to take advantage of ambient daylight and periods of inactivity. The Energy Management Team worked with building managers and users to pilot a room to verify the ambiance of the room was maintained. Lights are now on for ~35 hrs/wk, down from about 168 hrs/wk. The electricity savings are 278,560 kWh/yr for an annual savings of over $21,000.