Cooper Square Realty, manager of the 20-story towers, in partnership with Solar Energy Systems, now has a functioning 54.3 kilowatt DC solar photovoltaic system on their roofs.

``"Installing solar panels on the bulkhead of a 20 story building in the middle of Manhattan presents an obvious physical challenge. From an electrical standpoint, older NYC buildings can offer a variety of infrastructure challenges as well,’’ said David Buckner, president of Solar Energy Systems.

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