Metropolis Farms, which operates out of a warehouse in South Philly, has switched on its massive 100,000 sq. foot rooftop array, according to a company blog post. The system's 2,003 solar panels generates more than half a megawatt of energy to entirely power an indoor vertical farm being built on the floor underneath.
The "world's first completely solar-powered indoor farm" will grow the equivalent of 660 outdoor acres' worth of crops annually after planting starts in November, the company announced.
"Before starting this project, the fourth floor of this building was only growing pigeons," the blog post said. "But now, using our innovative technology that can uniquely grow everything, this solar powered indoor farm will be growing fresh tomatoes, strawberries, lettuce, herbs, broccoli, and other crops for local Philadelphians."
"We feel this inherently demonstrates the wonder of this new industry we're helping create, the industry of indoor farming."
Critics, however, say that the growth lights and water pumps are too energy-intensive and prohibitively expensive to operate.
But Metropolis Farms contends that its new solar rooftop "will provide a sufficient amount of energy to power the farm below."
"The truth is, like any technology, indoor farming is constantly improving upon itself," the company points out. The farm has achieved further energy efficiencies through "innovative lighting (not LEDs), BTU management systems, and other means to dramatically reduce the amount of energy our farms are using."
The company adds it is "on the cusp of a breakthrough in a technology that will reduce our energy usage even further" and will be demonstrating the advancement at this year's Indoor Ag-Con in Philadelphia.
"We got into vertical farming to help the planet and local communities. And that mission includes a commitment to using renewable energy when and where appropriate to reduce our carbon footprint as much as possible," Metropolis Farms says.
"We hope others will follow our lead and start building farms of the future, so communities everywhere can benefit from having a quality local food source that grows crops responsibly."