The story has been corrected on the wire and the 10th through 12th paragraphs now read as follows:

Another green approach was taken by Alan Hirsch, executive vice president of Sea Gull Lighting Products LLC, in Riverside, N.J. Last fall, he completed a 500-kilowatt system that provides 20 percent of the power needs for a 500,000-square-foot warehouse Monday through Friday. On weekends, the panels can provide all of the power needed. The solar panels take up about 60,000 square feet on his warehouse roof.

Hirsch's company is using SunEdison LLC of Baltimore, a solar services company that installs the system and continues to own it. Sea Gull, however, pays a rate for the electricity it uses that's below what it would pay if it bought from a local power provider, he said.

As long as the price of electricity doesn't go down, Hirsch said, the agreement with SunEdison makes sense. "I don't know of anybody who thinks electricity is going to be cheaper," he said.