Dive Brief:

A Chicago soap factory will be home to the world’s largest rooftop greenhouse this fall after the 75,000-square-foot space — built by urban greenhouse company Gotham Greens — is fully planted.

Between a wind turbine and “solar trees” that move with the sun, renewable energy produced by the $30 million, eco-friendly factory — occupied by soap manufacturer Method — generates one-third of the total energy the building uses.

The greenhouse, bigger than a football field and at least as big as an average-size city block, is designed to grow up to 1 million pounds of greens like kale, arugula and lettuce, which will be planted in a hydroponic system that requires no soil.

Dive Insight:

The high-tech greenhouse, whose temperature and irrigation will be computer-controlled, demonstrates Method’s commitment to what Chief Greenskeeper Saskia Van Gendt called “the highest standards of green building.”

To support the weighty greenhouse, the company reinforced the roof, which, once planted, will help insulate the factory — designed by William McDonough + Partners and Heitman Architects — and keep heating and cooling costs lower.

Once the greenhouse is fully planted, Gotham Greens will distribute the greens it produces to local stores and restaurants.

"We need to use our urban spaces more efficiently," Van Gendt told Business Insider. "Rooftop greenhouses are a representation of a model of doing that."