Figure 1: Each floor of the 21-story Phillip Burton Federal Office Building in San Francisco is more than 60,000 square feet. The lighting controls testbed occupies the third, fourth and fifth floors.
Vice President Al Gore's National Performance Review has given a Hammer Award to a team of private and public entities, including several Center researchers. The team is working to turn San Francisco's Federal Building at 450 Golden Gate Avenue into a showcase of energy-efficient technologies that could cut the federal government's annual energy bill by a billion dollars. The Hammer Award recognizes teams of federal, state, and local employees and private citizens who have made government more efficient and effective.
A study of potential savings by the team's energy modeling specialists found that the new technology and control system could reduce the Philip Burton Federal Office Building's energy use by 25 percent, saving $450,000 per year. The 1.4 million square foot structure is the largest federal building west of the Mississippi River. Energy-saving technologies being demonstrated at the building could save up to one-third of the federal government's annual energy bill of $4 billion if implemented in all federal buildings.
Figure 2: A contractor installs a dimming electronic ballast in a three-lamp lighting fixture at the Federal Building.
The team retrofitting the building consists of personnel from the Center for Building Science, the General Services Administration, Pacific Gas & Electric Company, the National Institute of Standards and Technology, and Energy Simulation Specialists. Members of the Center's Lighting Research Group and the Applications Team, which focuses on designing and implementing advanced energy-efficient demonstration projects, provided engineering expertise.
An advanced lighting controls testbed designed by Francis Rubinstein of the Lighting Research Group includes energy-efficient lighting for three floors of the building and a new automated control system. "Previous research that we've done at a demonstration site in Emeryville, California, has shown that by using integrated automated lighting controls, it's possible to reduce lighting energy use by up to 35 percent compared to a system without controls," says Rubinstein. "These controls include, among others, automatically dimming the lights when daylight is available, dimming or turning lights off automatically when a space is unoccupied, and compensating for lumen loss as lights age. However, these 'first-generation' controls didn't have the intelligent features of current systems, and they were difficult to calibrate and maintain."
New lighting installed in the building includes more than 1,200 dimmable electronic ballasts, 3,600 efficient lamps, dozens of light and occupant sensors, manual and remote-control dimmers, and smart control panels that respond to changes in a space's occupancy and available daylight. Nearly 200 meters are monitoring the energy use of the testbed down to the level of individual rooms to determine how much energy and money the new systems are actually saving. The testbed is intended to prove that the more advanced second-generation lighting controls are cost-effective and energy-saving. It will also provide a basis for designing and specifying advanced lighting control systems in federal buildings throughout the country.
Figure 3: Occupant sensors, photocells, manual switches, and energy monitors are all connected to 40 "smart panels" distributed stragetically throughout the three-floor testbed. All the smart panels are interconnected and communicate over a simple twisted pair of wires.
The automated control system that regulates lighting will be coupled to other energy management systems, which regulate the building's heating, ventilation, and air-conditioning systems using a nonproprietary communications protocol standard called BACnet (building automation control network). The BACnet-based energy management and control system will let building managers monitor and control the lighting, HVAC, and metering systems, even if they are from different manufacturers.
Interconnecting all the meters in the Federal Building will help its operators provide the optimum level of lighting, heating, air conditioning, and other energy-consuming services using the lowest-cost energy. The GSA plans to interconnect other federal facilities in the San Francisco Bay Area using BACnet. Since the energy use of all these buildings will appear as a single account to the utility, GSA will get lower electric rates as a higher-volume user.
Center staff participating in the project include Rubinstein, Judy Jennings, Doug Avery, Dale Sartor, Steve Kromer, Kris Kinney, Joe Huang and Rick Diamond.
--Allan Chen
Dale Sartor
The Applications Team
(510) 486-5988; (510) 486-5394 fax
Francis Rubinstein
Building Technologies Program
(510) 486-4096; (510) 486-6940 fax
This work is sponsored by the U.S. General Services Administration, the U.S. Department of Energy's Federal Energy Management Program, and its Building Technology Program, the Pacific Gas & Electric Company and the National Institute of Standards and Technology.