Here's a new twist to the greening of Lancaster.

Six city businesses will share a $479,333 state grant to Lancaster County to build green or "living" roofs.

The grant announcement from Gov. Ed Rendell's Energy Harvest program came Tuesday, the same day Mayor Rick Gray signed a national pledge for the city to work toward reducing greenhouse gas emissions.

In addition to reducing global warming emissions by cutting down on the need for so much air conditioning and heat, the green roofs reduce stormwater runoff, improve air quality, add habitat for birds, bees and other insects, and will break up a uniform sea of black above ground.

"One of the goals is to mitigate the urban heat island effect," added Mary Gattis Schell, senior environmental planner with the county Planning Commission.

Millersville University will measure the environmental benefits from the green roofs.

Also receiving an energy grant was Franklin & Marshall College, which will get $202,473 for a 26.6-kilowatt solar photovoltaic cell system to be built atop the Hackman Physical Sciences Laboratory. A solar photovoltaic cell converts energy from the sun into electricity. Twenty-six kilowatts is approximately enough electricity to power two small homes.

In addition to generating part of its own power, the project would eliminate the need for commercial electricity that is often generated by the burning of polluting fossil fuels.

It's estimated that deferred power production will prevent 3,289 pounds of sulfur dioxide, which contributes to acid rain, and 2.3 million pounds of carbon dioxide, a global warming gas, per year.

The two grants total nearly $682,000 and are among grants totaling $5.4 million for 28 projects statewide to generate clean and renewable energy.

The green roof grants will provide some but not most of the $1 million estimated to build the living roofs on 79,000 square feet in the city.

Planning to build green roofs are:

• New YMCA on Harrisburg Avenue.

• Renovation of the Bare Building, the former city police station, 202 N. Duke St.

• National Novelty Brush Co., 505 E. Fulton St.

• Penn Stone, 190 W. Ross St.

• Two Dudes Painting, 744 Poplar St.

• Box Company Flats, 225 E. Grant St.

Columbia Borough also was to share in the grant, but has dropped plans for a green roof on borough hall because of structural problems, Gattis Schell said today.

Green roofs might be considered giant flowerboxes atop reinforced roofs.

Roofs need to be strong to handle the extra weight of soil and plants. The plants add oxygen to the air and filter out pollutants, while the soil absorbs stormwater runoff that can carry pollutants from streets and sidewalks into streams.

The soil also insulates the building underneath, cooling it in summer and keeping warmth inside in winter.

Gray and other city officials have said in encouraging green roofs that the structures should not face building-approval obstacles.

Partners on the six green roof projects include Millersville University, the Lancaster County Redevelopment Authority, Lancaster County Career and Technology Center, Lancaster chapter of the Sierra Club, Lancaster Investment in a Vibrant Economy and the county Engineer's Office.

The grants were announced by Gov. Ed Rendell Tuesday under the Energy Harvest program launched in 2003 to promote awareness and build markets for cleaner or renewable energy technologies.

"Rather than continuing to rely on oil supplies that may come from politically unstable or hostile nations, or electricity derived from dirtier fossil fuels, we're investing in our future by supporting the development of alternative and renewable technologies that will strengthen our economy, create new jobs and protect our environment," Rendell said in a press release.

"These projects illustrate the interest and commitment that companies, universities and other organizations have expressed in investing in Pennsylvania's new energy economy and creating opportunities here."

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