Unveiled at the International Building Exhibition (IBA) in Hamburg in 2013, the world´s first bio-reactive façade generates renewable energy from algal biomass and solar thermal heat. The biomass and heat generated by the façade are transported by a closed loop system to the building’s energy management centre, where the biomass is harvested through floatation and the heat by a heat exchanger. Because the system is fully integrated with the building services, the excess heat from the photobioreactors (PBRs) can be used to help supply hot water or heat the building, or stored for later use.