Featured by Crain’s New York. 

A law that requires the city’s biggest buildings to log and report their energy usage is paying off, officials said Wednesday. Thousands of structural behemoths in New York City have cut their greenhouse gas emissions by 8% and energy usage by 6% over a three-year period without necessarily making any upgrades.

“Clearly, building owners are responding to the information they are receiving on their utility usage,” said Department of Buildings Commissioner Rick Chandler in a statement.

The information was contained in a report authored and released by the city and two nonprofits, Urban Green Council and New York University’s Center for Urban Science and Progress. Under the 2009 law, city- or privately owned buildings over 50,000 square feet are required to report their energy and water use annually. That adds up to about 15,000 properties. Although some of the reduction was likely due to energy retrofits or upgrades, experts said the overall numbers prove the law’s basic idea: owners will reduce their power consumption if they see how much energy they are using compared with other buildings of similar size.