NYC's Historic Buildings Steal the Energy-Efficiency Spotlight

In New York City, the heating and cooling of buildings accounts for a staggering 80 percent of greenhouse gas emissions. For the last three years, the Bloomberg administration has mandated that the city's largest commercial buildings track their energy usage to help attain its goal of cutting all emissions by a third by 2030.

"Hurricane Sandy has underscored the urgency of such efforts, and continuing climate change is expected to result in more severe storms and flooding," reports Mireya Navarro, adding, "[w]hile the city’s biggest commercial structures have been required to report energy use since 2010, this is the first year public disclosure has been mandated under a 2009 law that is among the first in the country to follow how buildings use energy." According to Navarro, "[b]ig residential buildings will face the same disclosure requirement next year" shedding greater light on how buildings use energy in the city that never sleeps.

Scores ranged from 3 to 84, with a median score of 68 for all commercial buildings reporting data. Navarro writes, "Older buildings tend to have higher Energy Star scores because they have thicker walls, fewer windows and less ventilation — superior 'thermal envelopes,' as a report [PDF] on the early results puts it. They are also less suited to energy-gobbling activities like computer data crunching, the downfall of some youthful but middling performers."

Though the positive performance of older buildings was astonishing to many, the less than stellar performance of LEED-rated buildings wasn't unexpected. “It’s disappointing, but at the same time, it’s not surprising because there are so many things that could be happening,” Scot Horst, senior vice president for the LEED program at the Green Building Council, said of some scores. "Poorer scores for newer and LEED-rated buildings can be attributed to the use of new building materials and techniques, as well as negligent occupant behavior such as leaving lights or computers on, and to overall building control management, which can be lax."