Lilly is a passive-tower designed for Bryant Park in Manhattan, a sustainable prototype for the future of our cities. Lilly eliminates conventional heating and cooling via a geo-thermal system, provides heat-exchanging natural ventilation, irrigates an insulating blanket of Asian lilies through rainwater harvesting. She is comprised of 18 floors of apartments and 23 floors of office space with multiple amenities along with utility spaces. In addition to being sustainable, Lilly looks sustainable with its massive green roof/facade, engineered to withstand the elements with proper maintenance.