With the cost of lighting accounting for more than a third of the energy bills at most federal facilities, officials at the General Services Administration know that it will take more than upgrading to newer florescent and LED lighting to make government buildings more energy efficient. It also means finding ways to efficiently install an array of new and smarter technologies.
The stakes, however, are significant. GSA boasts a portfolio of federal buildings that amounts to nearly 10,000 assets. The upshot, though, is that those buildings offer a rich laboratory to evaluate green technologies.
That’s exactly what’s behind GSA’s Green Proving Ground (GPG) program.
The Green Proving Ground works with the Energy Department’s national laboratories — the Lawrence Berkeley National Laboratory in California, for example — to evaluate emerging green building technologies.
Recent GPG projects on reducing power consumption involve, for example, new lighting technologies and advanced power strips. Lighting together with power loads from equipment plugged into power-strips account for nearly 65% of electricity consumption in federal office buildings, according to GSA.
“The Green Proving Ground leverages GSA’s own real estate portfolio as a test bed to evaluate the viability of emerging building technologies and practices to save energy, water and reduce operational costs,” Eleni Reed, chief greening officer at GSA, told Breaking Gov. “Technologies that allow us to use less electricity and power will help us improve energy costs in government buildings.”
“We measure how well these technologies work, in terms of their environmental performance, how easy they are for our facility managers to maintain and operate, and how cost-effective they are,” Reed said.
“When appropriate, the buildings’ occupants participate in surveys on how well these technologies are working for them. We then take these results and use them to prioritize investments in those that will make federal buildings more efficient.”
A key area of concentration for GPG is lighting technology — with good reason. Despite widespread adoption of efficient lamps and ballasts over the past several decades, lighting still accounts for more than a third (39%) of the electricity used in U.S. federal office
buildings, according to GPG program manager Kevin Powell.
“Emerging digital lighting control technologies, particularly those designed for open-plan settings, promise to cut that energy use in half,” Powell said.
GSA has an abiding interest in identifying energy-efficient lighting solutions that can help its client agencies conserve energy and reduce costs, GSA officials said.
To this end, GPG last year worked with the Lawrence Berkeley Lab to evaluate the performance of occupant or workstation responsive lighting systems, concluding that the new systems in the study “delivered deep energy savings, comparable if not superior lighting levels and increased occupant satisfaction.” Depending on the building site, energy savings ranged from 27% to 63%.
In conducting the study, GPG and Lawrence Berkeley officials retrofitted seven sites at five GSA buildings in California with workstation responsive lighting systems and compared the performance of the new systems with to the systems in place prior to the retrofits.
In general, the pre-retrofit lighting systems consisted of recessed light fixtures that were regularly spaced in open areas or distributed in private offices to conform with office layouts. In contrast, the retrofit green systems were centered over each cubicle in the open office and furnished both upward- and downward directed light, according to the report.
The retrofitted lighting technology used three elements to control work-station lighting: institutional tuning or scheduling, where building managers program default light levels and hours of operation; occupancy sensing, which adjusts light levels in response to the presence or absence of work-station occupants; and personal control, in which occupants adjust workstation lighting levels to suit their preferences.
The circuits that furnished power to lighting fixtures were metered during both pre- and post-retrofit periods at each site, which were chosen within the five buildings to capture a diversity of office environments, workstation occupancy patterns and other site-specific conditions.
To track critical metrics and calculate annual savings, “power data was converted to lighting power density, which was in turn converted to energy use intensity, or EUI, the unit of measurement used to describe building energy use,” according to the report.
The largest energy savings figure, 63% was achieved at a call center at the Royal Federal Building in Los Angeles. Researchers attributed the high savings to “variable levels of work-station occupancy” during the call center’s long operational hours. In contrast, sites that showed lower levels of energy savings-in the 20% range–were spaces where “the tenant required illumination for a 12-hour workday, five days a week, and where employees were at their desks most of the day.”
GPG also conducted a followup survey that indicated that workstation occupants were generally more satisfied with the retrofitted lighting systems, providing better quality light and less glare, they said.
Another recent study, the Plug Load Control Study, assessed the use of advanced power strips in eight GSA buildings in the mid-Atlantic region. According to GSA, plug loads account for about 25 percent of total electricity consumed within federal office buildings. Advanced power strips can help save energy by controlling plug-in devices according to a schedule or based on a whether a given device crosses a power threshold.
In studying the green impact of smart power strips, GPG collaborated with the Energy Department’s National Renewable Energy Laboratory , monitoring more than 295 devices during the research period.
Deploying advanced power strips resulted in an average energy savings of 48%, the study found. The largest savings were gained when schedule timer controls were applied to devices-such as printers and copiers-that were powered 24/7. Schedule-based advanced power strips reduced plug loads at workstations by 26% and nearly 50% in printer rooms and kitchens.
“Plug loads are an increasingly large portion of building energy profiles,” said John Remis, facilities services manager at the Richmond, Va., Federal Building. “Managing those loads is key to making federal buildings energy efficient.”
In the long run, scaling deployment of proven energy-saving technologies, such occupant responsive workstation lighting and advanced power strips, across multiple buildings will require strong partnerships between GSA program offices and regional personnel, including individual building management teams, Reed told Breaking Gov.
“This is a challenge that GSA is meeting head-on by bridging our expertise in procurement with our knowledge of building design, management and operation, by working across business lines, and by developing tools to build a common set of ‘how to’ knowledge that will support implementation,” she said.
GSA has announced that it plans to test and evaluate 12 additional emerging green technologies in select federal buildings, including wireless lighting controls, LED bulbs, wireless pneumatic thermostats, solar thermal collectors and water-saving landscape irrigation systems.