Existing office towers present an opportunity to think about energy generation differently. This projects office floor conversion incorporated a Net Zero Energy strategy that went beyond the traditional boundaries of office space to incorporate a base building upgrade. Hidden from view is a new mechanical system that captures waste heat from existing systems on the buildings mechanical floor to create new value. The result is a core building system that produces nearly three times the amount of energy than will be used by the tenant who installed it. When we think about design solutions as whole systems, we create unique opportunities to increase efficiency and generate resilience.