When buildings of various use-types are served by a district energy system, many societal benefits occur, including improved capacity utilization, reduced energy use, and more cost-effective redundancy. In addition, a central system may benefit financially from commodity leveraging, utility incentives and cogeneration. Energy conversion and transport efficiency for steam and hot water are explored and presented. System optimization curves, including generation and distribution, are presented along with long-term financial comparisons to decentralized systems.