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Best Practice Guide |
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Commercial Office Buildings |
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Case StudyGlenborough Realty TrustProperty Name: First Financial Website: www.glenborough.com
Glenborough Realty Trust initiated a company-wide energy management program in 2004 that has already achieved remarkable cost savings as well as national recognition from U.S. EPA's ENERGY STAR program. Glenborough pulls together an Energy Team made up of three important subgroups:
Glenborough leverages the expertise and resources of its many partners. Servidyne Systems, Inc., for example, assisted with the development of the energy management program, adapting ENERGY STAR tools specifically to fit Glenborough's needs. Servidyne provides ongoing analysis of energy performance at each property, enabling it to identify and recommend energy-saving opportunities as these arise. In 2004, the first year after initiating the program, Glenborough invested nearly $1 million on 19 separate Energy Management Related Projects (EMRP) that collectively achieved annual energy savings of approximately $125,000 or $0.039/SF. For these, Glenborough received about $100,000 in rebates. As a result of its investments, eleven of Glenborough's properties have earned the ENERGY STAR label, with more to follow. Another important partner is Light Source, a specialty lighting distributor and member of the U.S. EPA's Greenlights program. Glenborough purchases lighting equipment from Light Source using an online, customized inventory that lists all equipment in each Glenborough building. Light Source routinely analyzes stock and usage at each building in order to recommend to Glenborough energy-saving products that last longer or are less expensive, choosing among the best products from multiple manufacturers. Glenborough's corporate offices in San Mateo serve as a demonstration site for experiments with new building technologies and operational best practices. Various lighting controls, for example, have been tested in an attempt to maximize efficiency and optimize control. One test involves a stairwell fixture that incorporates both a low-wattage compact fluorescent light (CFL) and a 360-degree motion sensor with photometric technology. The stairwell fixture reduces energy-use by limiting run-time, yet ensures that building occupants can move through stairwells safely and securely. Once proven, new technologies are installed throughout Glenborough's other commercial properties across the country. Glenborough is expanding its energy management program for 2005. 33 EMRPs are underway, totaling $1,308,500 in energy efficiency investments that are expected to yield annual cost savings of $372,900. Rebates for these projects are expected to reach approximately $338,000, making payback on investment in less than three years. Because of its sustained commitment to energy efficiency, U.S. EPA's ENERGY STAR program recognized Glenborough as an Energy Leader - one of only two in California and only eighteen nationwide. At First Financial Plaza in Encino, retrofits to and redesign of the heating, ventilating, and air conditioning (HVAC) system resulted in dramatic energy savings. An old 375-ton R-12 centrifugal chiller near the end of its useful life was replaced with an energy-efficient Carrier 19XRV chiller. The new chiller uses R-134A as a refrigerant, eliminating all chlorofluorocarbon (CFC) emissions - CFC is known to deplete stratospheric ozone and has been phased out of production by all U.S. refrigeration and air conditioning manufacturers. The chiller replacement is expected to save about $15,500 each year while reducing electricity consumption by 222,535 kWh. The project qualified for a $15,750 utility rebate from the Department of Water and Power. Facility engineering staff also replaced the pneumatic plant controls with a DDC Energy Management System (EMS) and, through trending, has changed the operations of the air handling subsystem, which was viewed as the least efficient component of the entire HVAC system. Staff lowered set points for the chilled water temperature so that fans do not need to be run as hard or as long to achieve the same degree of cooling. Variable frequency drives (VFDs) were added to fan motors, allowing the fan system to adjust according to actual HVAC loads, rather than running full-on or full-off. A VFD was also added to the cooling tower. These VFDs enable Glenborough to maximize the efficiency of its variable air volume fan system and cooling tower temperature control, achieving significant savings during off-peak hours such as weekends and evenings. Tight monitoring of the system allows engineering staff to adjust set points so that the use of air economizers' "free cooling" is increased. Air economizers use outside air, rather than HVAC-conditioned air, to cool a building when outdoor temperatures are colder than indoor. In certain months, the HVAC system can operate all day with the economizer and no mechanical cooling. The energy management system (EMS) at First Financial was redesigned to take advantage of HVAC upgrades. Equipment schedules were also adjusted, particularly lighting during off-peak hours. Rather than lighting all areas 24 hours a day/7 days a week, Glenborough now bases equipment schedules on actual occupancy and building hours - 8AM to 6PM on weekdays, 8AM to 2PM on Saturdays, and closed on Sundays. A separate project retrofitted all lighting in the elevator lobby to compact fluorescent lamps (CFLs), which typically save as much as 66% on electricity use over standard incandescent lamps. Moving forward, in 2006 occupancy sensors will be added to all restrooms including vestibules and tenant spaces where these are not already present. In addition, 44 heat pumps will be tied to the EMS for better control and ultimately achieve an improved operating efficiency. Energy projects at First Financial have reduced total electricity use nearly 15% and lowered costs by 12% -- over the first eight months of 2005, Glenborough has saved more than $35,000. |