The Plantagon CityFarm will grow greens in vertical towers under LED lights. By capturing the heat from the lights the farm operators can send it into a heat storage system for the office building, to help keep the offices warm through the winter.

The system will save the office building 700,000 kilowatt-hours of energy a year, worth roughly three times as much as the previous tenant of the basement was paying in rent.

Says Plantagon cofounder Hans Hassle, “If you really want to grow things in the city, you have to find new business models that actually make the food not too expensive in the end.”

The company plans to sell food directly to people working in the offices above, along with two restaurants that are located in the high-rise. Roughly a third of the produce will be sold to nearby grocery stores, all close enough that the greens can be delivered without fossil fuels. Another third of the produce will be sold in an on-site store in the skyscraper.

Like other indoor farming, the Plantagon system also uses a tiny fraction of the water used on outdoor farms. The heat is captured in water that travels in tubes over the LED lights, and then sent into a heat pump system. Carbon dioxide from the offices will also be sent to the farm, and fresh oxygen from the plants will be sent back to office workers.

The company is currently crowdfunding investment in the first farm. Hassle hopes to involve as many people as possible. “To us, food production is not like running any business–food is like water, it’s a human right,” he says.

Source: This Underground Urban Farm Also Heats The Building Above It