How the Commercial Sector
Can Save Energy

Office buildings, department stores, and other buildings in the commercial sector consume about one-third of our nation's electrical energy. Deploying energy conservation measures in many large commercial buildings could reduce this consumption significantly, according to several recent ORNL studies.

A large office building in Washington, D.C., was studied by Howard McLain, S. B. Leigh, and Mike MacDonald, all of the Existing Buildings Research Group in the Buildings Technology Center of ORNL's Energy Division. Using a computer program, they analyzed the all-electric United Unions building before and after energy conservation measures were installed. These measures included modification and replacement of light fixtures and improvements to the heating, ventilating, and air-conditioning (HVAC) system.

ORNL researchers analyzed the United Unions office building (shown here) in
Washington, D. C., before and after energy conservation measures were installed.

The researchers simulated the building's energy consumption using the DOE-2.1D computer program. The program was then used to estimate the energy and cost benefits of the individual conservation measures for a typical meteorological year.

"After the conservation measures were installed," McLain says, "the United Unions building used 37% less energy per year than it did before. The savings in energy costs totaled $163,000 per year, or 35% of the original building energy cost. This savings would cover the cost of the installed measures in 4.3 years."

Half of the savings was the result of the light-fixture changes. The other half was from HVAC system improvements.

"The newly installed computerized energy management and control system, while convenient for building operators, did not contribute much to energy savings," McLain says, "because the operators were already doing a good job with manual controls."

At ORNL, a building energy conservation experiment was carried out at the Energy Division Office Building (Building 3147). "In this building," MacDonald says, "new fixtures have fewer ballasts and fewer but more efficient lamps than the old fixtures. This change reduced the total amount of light by about 50% based on the fact that the building had more lighting than DOE standards allow. The electricity used for lighting was reduced by 70%, and total electricity use for this all-electric building decreased by almost 30%. However, lighting quality appears about equal to previous conditions."

In another study, MacDonald found that Commonwealth Electric, an electric utility in Massachusetts, saved energy in a demand-side management (DSM) program by giving tenants and owners of commercial buildings financial incentives to install more-efficient lighting.

"Throughout their history, utility DSM programs have saved a total of only about 0.3% of the energy used by residential and commercial buildings in the United States," he says. "Utilities are more strongly motivated by the potential to cut peak demands for electricity to reduce the need for costly new power plants and the associated financial risk.

"To achieve substantial savings, the United States needs a program 10 times larger than the collection of current DSM programs. An infrastructure of partnerships is needed to make it easier and more attractive for owners of commercial buildings, especially the large ones, to alter and maintain their buildings to save energy. Such an infrastructure is now being developed through the Rebuild America initiative."

In October 1993, President Clinton's Climate Change Action Plan was initiated in response to the Earth Summit in June 1992 in Brazil, which drew representatives from more than 200 countries. The plan's first item of action is the "Rebuild America" initiative, because energy use in buildings accounts for about 36% of the carbon dioxide emissions produced in the United States. These emissions could contribute strongly to global warming.

BTC's Existing Buildings Research Group was one of the original participants in formulating the Rebuild America initiative. Much of the input came from ORNL's Bill Mixon (now retired) and Mike MacDonald. ORNL is now developing a handbook for Rebuild America "partners," in collaboration with other national laboratories and private organizations.

"Rebuild America," MacDonald says, "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."

Six partners were selected by DOE for financial assistance in the first round of partner selection. These six partners have goals of retrofitting 200 million square feet of commercial and multifamily buildings to save over 0.5 billion kilowatt hours per year of electricity and over 0.01 quadrillion British thermal units per year of natural gas.

In short, Rebuild America will make institutional arrangements to deploy existing energy-efficiency technologies in commercial and multifamily buildings. These measures can save significant amounts of energy and money and help protect the environment.

Carolyn Krause

Where to?

[ Next article | Search | Mail | Review Home Page | ORNL Home Page ]