At the core of this multifunctional building is a multi-storey hydroponics greenhouse (Urban farming), positioned on the south façade of the tower, with office spaces behind. The greenhouse produces 180 kg of vegetables and herbs per day, enough for feeding 500 people daily. The greenhouse uses waste from surrounding functions as resources, while giving back not only food, but also energy for space heating and clean indoor air. The circular concept minimizes the use of energy, water and resources in the entire building while leaving no waste behind.

 

In order to achieve high production capacity, the greenhouse requires sufficient amounts of water, lighting, nutrients and CO2, all of which is collected or produced on site. Beside rainwater collection and optimal daylight conditions, the innovative design is reflected in the inter-connection of all zones of the building, enabling constant flow of nutrients and CO2. By filtering the exhaust air from the 500 cars, over 75 kg of CO2 is extracted from the garage every day, which translates to 27 tons CO2/year. The nutrients for plants growth are produced on-site as well by digesting bio waste from the production itself, remaining food from the restaurant as well as black water from the toilets in the offices and apartments. The anaerobic digester, located in the basement, simultaneously produces bio gas, liquid digestate and solid digestate. The biogas is directly used for cooking in the restaurant. Liquid digestate provides nutrients for the hydroponics. Solid digestate is dried using excess heat in the summer and used as biomass for space heating of the offices and apartments in the winter.