Energy
A major research university such as the University of Maryland requires a lot of energy to operate. With an energy bill of over $50 million per year, climbing energy rates, and growing concerns about effects of greenhouse gas emissions on our environment, the University is rapidly implementing energy efficiency and conservation upgrades.
Energy Performance Contracts
The state of Maryland recently pre-qualified a group of Energy Service Companies (ESCOs) to make performance contracts available to state agencies, including the University. Performance contracts allow energy conservation measures and technologies to be installed without any upfront capital cost to the sponsoring agency. The ESCO is repaid through utility bill savings over the term of the contract. The ESCO guarantees projected savings and a measurement and verification program ensures that these savings are realized.
In spring 2008, Constellation Energy and Johnson Controls started detailed energy audits to determine the best strategies to reduce energy consumption on campus. Each ESCO was assigned a group of buildings to study and propose energy conservation measures and facility improvements. The proposals will address areas such as lighting; water use; heating, ventilation, and air conditioning (HVAC); building envelope; and building automation controls. In addition, the proposals will detail the cost to implement each measure, the savings associated with that measure, and payback.
Energy Projects Save $28,209 in First Three Weeks
University of Maryland and Johnson Controls have begun implementation of the $20,000,000 energy conservation project. The project is designed to save nearly $2,000,000 a year in energy and reduce the CO2 emissions by over 4,200 tons per year. Just 3 weeks after completing some of the first energy conservation measures, UM has realized a $28,209 savings and 59,946 lbs of CO2 reduction, the equivalent of conserving 5,214 gallons of gasoline.
Heat and Power Generation
The recipient of the EPA’s 2005 Energy Star Award, the University’s Combined Heat and Power Plant was completed in 2003. The system produces all of the steam required for heating and in some cases cooling for the University. The plant is capable of producing up to 90 percent of the University’s electric demand in the winter and around 50 percent of the summer demand. Consisting of two gas-fired combustion turbines, one steam-driven electric turbine, and two heat recovery steam generators, the system operates at efficiencies of around 70 percent, significantly higher than like-sized independent steam boilers and electric generators. The system requires approximately 16 percent less fuel than typical purchased electricity with separate steam generation, resulting in a reduction of nitrous oxide, sulfur dioxide, and roughly 53,000 tons of carbon dioxide annually.
Thermal Storage
The University operates a thermal energy storage system that cuts energy costs and reduces energy consumption during hours of peak demand. The system, located underground behind Stamp Student Union, cools water at night, storing it for daytime use. The chilled water is used to cool three major facilities: the Clarice Smith Performing Arts Center, Stamp Student Union, and the Riggs Alumni Center. Chilling water at night cuts down on peak-hour energy costs and reduces the load on electric generation plant during the day which helps reduce the plant’s emissions during times of high ozone levels, such as “Code Red” air quality days.
Lighting
Hallways across campus now use 80 percent less energy than they did before a campus-wide lighting retrofit project started in spring 2008. The Hallway Lighting Project, coordinated by Facilities Management, accomplished this by replacing existing T8 fixtures with new T5 volumetric light fixtures and by reducing lighting levels to those specified by the Illuminating Engineering Society of North America (IESNA).
Lower lighting levels were tested in nine different hallways on the first floor of the AV Williams building last fall. Building occupants provided feedback that helped Facilities Management choose the lighting arrangement that offers sufficient lighting for safety and comfort while reducing energy use. This combination of using energy efficient fixtures and reducing lighting to sufficient levels will save approximately 6,600 Megawatt hours of electricity and 5,200 tons of CO2* each year. The project cost of $1.8 million will be paid back through energy savings in 2.5 years**.
The Department of Recreation Services completed a lighting retrofit at the Eppley Recreation Center West Gym and Ritchie Arena by converting 400 Watt lights to 320 Watt Pulse Start. Conversion minimized waste by reusing existing fixtures and scheduling the retrofit at a time of a scheduled lamp replacement. The conversion is projected to save approximately 61,100 kwh and $6,600 per year in the West Gym and 30,400 kwh and $3,300 annually at Ritchie (at the current $0.1082 per kWh utility rate). The Department of Residential facilities completed an extensive program to replace all “EXIT” signs energy-saving LED exit signs. The conversion which includes residence halls, fraternity/sorority row houses, and departmental office space will result in a reduction of energy consumption by 30%.
* based on the present energy “mix” used on campus
** based on the present energy cost of $0.1082 per kWh
Computers and Office Equipment
Software is being tested that automatically puts office computers in low-power states, (such as sleep for monitors and standby, hibernate and shutdown for PCs) when the machines are not being used. The software keeps a running total of the amount of energy being saved. On average, 200 kWh of energy per office PC is conserved, reducing CO2 emissions by as much as 440 lbs per PC per year. In addition, motion sensing power strips underneath desks are being tested which shut down office appliances such as personal printers, coffee makers, fans and radios.
CO2 Monitors
Ventilation systems pump air from the outside into buildings on campus to replace the CO2 that people exhale with oxygen. The pumps run on electricity. Previously, the pumps ran continuously at the same rate, regardless of whether the building was occupied or needed fresh air. Now, monitors are being installed that can slow or stop the pumps when the buildings contain the correct level of oxygen. The monitors start the pumps again when too much CO2 is detected and fresh air is needed.
Student Energy Audit
The Department of Mechanical Engineering offered a special topics class this past school year in energy audits. The students who took the course in the spring under Dr. W. Travis Horton audited the Engineering Lab building (#089). They were able to perform walk-through and energy survey analyses before providing a list of recommendations to reduce energy usage within the building by approximately 25 percent. The energy audit accounted for all energy that enters or leaves the building and included all electrical and heating, ventilation, air conditioning (HVAC) systems, as well as the building envelope itself. This summer, the class audited the Ellicott dining hall (#257). The students again made recommendations that would improve the building’s energy efficiency while simultaneously saving the University money. The greatest “bang for the buck” would come from the purchase of a 70 percent more efficient ventilation system that would pay for itself in less than 3.3 years.
For more info, visit Energy Conservation