A $100,000 study sponsored by building-owner interests has concluded there is no positive correlation between mandatory building-energy labeling and energy use. The six-month project was a response to increased interest among cities in passing legislation mandating energy scores and energy-efficiency programs.

"The biggest surprise to me was that we found, in what was a … comprehensive review of [labeling studies], no empirical evidence that these mandates have any effect on energy use," says Robert N. Stavins, co-author of "An Economic Perspective on Building Labeling Policies" and a professor of business and government at Harvard University. "No studies found a positive effect, and one study, in Denmark, found a negative effect."

In the U.S., Austin, San Francisco, Seattle, New York City, Philadelphia, Minneapolis and Washington, D.C., have mandatory labeling programs. Boston is considering such an ordinance.

In testimony on March 28 before Boston's City Council, Stavins said, "I am concerned about the city of Boston putting in place a policy that, from what I have ... studied, may not be effective, may be very costly and may therefore ... prove to be counterproductive, making Bostonians worse off, rather than better off."

Quantifying the cost of labeling a building is difficult, says Courtney McKay, a spokeswoman for the Building Owners and Managers Association International (BOMA), which co-sponsored the study with the Greater Boston Real Estate Board (GBREB)—also a co-author. "Each building has different variables, from size to the number of tenants to whether or not the energy company provides aggregated usage data or if the owner needs to ask each tenant to provide the information," says McKay.

Currently, no other cities are weighing mandatory labeling. Still, BOMA has made the study information available at www.boma.org. And GBREB has plans to conduct an empirical analysis of the performance of existing mandatory building labeling programs across the U.S.