White Is Green and Cool at Con Edison

NEW YORK ‑ Con Edison is turning roofs white so that they’ll be green.

As part of its effort to combat global warming and encourage energy efficiency, the company is installing white roofs on its Manhattan headquarters and other buildings.

Benjamin Franklin was one of the first to learn that light-colored surfaces reflect nearly all the light that hits them, while darker surfaces absorb the light and accompanying heat. Franklin placed square pieces of cloth on top of the snow on a sunny morning. He observed that the snow melted more quickly under the dark pieces.

Dark roofs radiate heat back into the atmosphere at night, a process called the “heat island effect.” The U.S. Environmental Protection Agency estimates that on a hot, sunny day, the sun can heat surfaces like urban roofs and pavement to temperatures 50 to 90 degrees Fahrenheit hotter than the atmosphere. Shaded or moist surfaces - often found in more rural areas - do not get as hot.

“Installing white roofs is one of many steps Con Edison is taking to fight global warming,” said Saddie L. Smith, the company’s vice president for facilities. “Our installation of a green roof at our Learning Center training facility and increasing use of alternative fuel and electric vehicles are other examples.”

Con Edison’s Mott Haven substation in the Bronx, the Astor and Parkview substations in Manhattan, and the Rockview substation in Westchester County are among the company buildings that have white roofs. The Newtown substation in Queens and the Academy substation in Upper Manhattan – both under construction - will also have white roofs.

Con Edison’s first “green roof,” an energy-saving plant system, is atop part of the company’s Learning Center facility in Long Island City. More than 21,000 plants occupy over a quarter acre. The plants absorb heat, keeping the building cooler and reducing the need for air conditioning. The roof is projected to save up to 30 percent of the Learning Center’s peak-cooling costs.

Adjacent to the green roof is a control roof with white and black membranes. Scientists at Columbia University are studying the relative energy savings of the white, dark and green roofs at The Learning Center.

Con Edison Chairman, President and CEO Kevin Burke joined Mayor Michael Bloomberg and former Vice President Al Gore recently at the launch of an NYC Service initiative called “NYC Cool Roofs,” which will use volunteers to coat roofs white. The mayor said that a cool “white” roof absorbs 80 percent less heat than dark roofs and can lower roof temperatures by up to 60 degrees and indoor temperatures by 10 to 20 degrees on hot days.

Con Edison is a subsidiary of Consolidated Edison, Inc. [NYSE: ED], one of the nation’s largest investor-owned energy companies, with approximately $14 billion in annual revenues and $34 billion in assets. The utility provides electric, gas and steam service to more than 3 million customers in New York City and Westchester County, New York.

Con Edison’s commitment to environmental responsibility has been recognized by the global Carbon Disclosure Project (CDP), Innovest Strategic Value Advisors, the U.S. Environmental Protection Agency, the U.S. Department of Energy and other organizations.