Currently, office buildings, department stores, warehouses, and other buildings in the commercial sector consume about one-third of the nation's electrical energy.
A team of ORNL researchers - Howard McLain, S. B. Leigh, and Mike MacDonald, all of the Existing Buildings Research Program in the Buildings Technology Center of ORNL's Energy Division - has studied a large office building in Washington, D.C. Using detailed measurements of energy data and a computer program, they analyzed the all-electric United Unions building before and after energy conservation measures - including modification and replacement of light fixtures and improvements to the heating, ventilating, and air-conditioning (HVAC) system - were installed.
The researchers studied the building's energy consumption, using a DOE computer program to estimate the energy and cost benefits of the individual conservation measures for a typical year.
"After the conservation measures were installed," McLain said, "the United Unions building used 37 percent less energy per year than it did before. The savings in energy costs totaled $163,000 per year, which is a 35 percent reduction in the original building energy cost. Half of the savings were the result of the light-fixture changes. The other half were due to the HVAC system improvements. The total savings would cover the cost of the installed measures in 4.3 years."
Energy savings measures are also being installed at ORNL, where measurements of building energy conservation savings were recently made at two buildings. New lighting was installed at the Plant and Equipment Division building and an Energy Division office building.
"In the Energy Division building," MacDonald said, "new fixtures have fewer ballasts and fewer but more efficient lamps than the old fixtures. This change reduced the amount of electricity used for lighting by 70 percent and cut total electricity use by almost 30 percent. Lighting levels were cut in half because the building had been overlit."
MacDonald also worked on a study of Commonwealth Electric, an electric utility in Massachusetts that had installed lighting retrofits for thousands of buildings in a demand-side management (DSM) program. For the three years the program was conducted (1990-1992), energy use was found to be reduced by more than 20 million kilowatt hours per year.
MacDonald cautions that the combined savings of all utility DSM programs conducted from the 1970s through about 1991 totals only about one-tenth of a quad (quadrillion British thermal units) per year for the commercial sector in the United States. This amount is about 0.3 percent of the energy used currently by U.S. residential and commercial buildings (two percent of commercial use alone).
MacDonald said, "An infrastructure of partnerships is needed to make it easier and attractive for owners of commercial buildings, especially the large ones, to alter and maintain their buildings to save energy. Developing such an infrastructure is the purpose of the Rebuild America initiative."
ORNL's Existing Buildings Research Program was one of the original participants in formulating the Rebuild America initiative, with input coming from ORNL's Bill Mixon and Mike MacDonald. DOE and ORNL have developed a summary brochure for Rebuild America, and a national solicitation for partners in the program will be issued this year.
"Rebuild America," MacDonald said, "will involve partnerships of state and local governments and others who will deal with engineering firms, financial companies, and commercial building owners. The partnerships will help get financing for installing energy conservation measures in commercial and multifamily buildings."
In short, Rebuild America will foster and enhance institutional arrangements to deploy existing energy-efficiency technologies in commercial buildings. These measures can save significant amounts of energy and money and help protect the environment.
ORNL, one of the Department of Energy's multiprogram research laboratories, is managed by Martin Marietta Energy Systems, which also manages the Oak Ridge K-25 Site and the Oak Ridge Y-12 Plant.