The Empire State Building – yes, that building, in New York City has implemented a series of energy retrofits that have reduced operating costs by $2.4 million in the first year alone. In the next few years, when the project is complete, the building is expected to reduce its energy use by nearly 40 percent–and save about $4.4 million each year. In the process the building is becoming a symbol of what can be done to reduce energy use in a cost effective manner in existing commercial buildings.

A team of real estate, energy service and climate experts worked over nine months to prove to the building’s owners that an energy efficient retrofit made economic sense. Johnson Controls, an energy service company, guaranteed that its portion of the work would provide roughly 20 percent savings for 15 years–or they would foot the bill for the difference.

A key component involved rebuilding the windows, reusing the existing glass, sash, and trim, and sandwiching a layer of insulating film between the two existing panes. This strategy created far less waste than tearing out the old windows and shipping in replacements.

More details on this new poster child for cost effective energy efficiency can be found at http://switchboard.nrdc.org/blogs/plehner/empire_state_building_cuts_ene.html