Joined by civic leaders, PECO is set to unveil its plans today for a 45,000-square-foot living roof atop a section of the headquarters for the Philadelphia-based electric and natural gas utility.
The planting of the green roof is an element of the utility's five-year, $15.3 million initiative to become more environmentally friendly. When it is complete, the living roof will be the largest on an existing building in urban Pennsylvania. It will be the first green roof on a company property, a spokesman said, but not the first to involve the utility.
In a project funded with a $50,000 grant from PECO, Temple University's Ambler campus, north of Philadelphia, completed a green roof on its Intercollegiate Athletics Field House in 2005. In the ceremonies scheduled for today, PECO President & CEO Denis O'Brien is to present a $50,000 donation to the Free Library of Philadelphia Foundation for its own living roof project. Philadelphia Mayor Michael Nutter is also scheduled to attend PECO's preview of its green roof plans.
PECO's green roof will sit atop an eight-story section of its headquarters. A taller section of the building, a tower whose two-and-a-half top stories form a marquee, is a hallmark of the city skyline.
The living roof is expected to absorb 60 to 70 percent of the estimated 1.5 millions gallons of rainwater that fall on the structure annually. During the green roof's peak growth period in summer, rainwater absorption is projected at 85 percent. During heavy storms, the roof is expected to reduce runoff by at least 50 percent.
The green roof is also expected to help insulate the building during poor weather and help cool it inside and out during warm weather. The ambient surface temperature of the living roof is expected to be cooler by 60 to 80 degrees Fahrenheit during the summer, compared with the ambient surface temperature of 150 degrees Fahrenheit on a conventional black roof, according to performance projections.
PECO announced other projects in its eco-friendly initiative last month. The utility serves 1.6 million electric customers and 480,000 natural gas customers in southeastern Pennsylvania. It is a subsidiary of the Exelon Corporation, which is based in Chicago. |