Excerpts from this GreenBiz.com website:

Rosmead, CA — March 28, 2008 — Southern California Edison is planning an ambitious 250 megawatt solar project that would plant solar panels on 65 million square feet of commercial rooftops.
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A 600,000 square foot facility is the first ProLogis site that would be topped with solar panels, Rosenblum said, and the company has more than 19 facilities in the project's area with more than 1 million square feet of roof space. SCE hopes to start the project off with several other partnerships, Rosenblum said. Working at such a large scale will help drive down the price of the solar panels as well as cover the largest swaths of space available quickly.
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Complete article