Synthesis and Design of a Trigeneration System of Large Public Buildings

Building energy systems, especially large public building energy systems (LPBES), are major energy consumers and pollutant emissions contributors. In this paper, a superstructure of LPBES incorporating the candidate equipments and their possible combinations are constructed. The thermodynamic performance model, investment cost model, CO2 emission model of the equipments are formulated. The variations of the energy demand and power importation price are addressed by multiple scenarios problem. A multi-objective mixed integer linear programming (MILP) model is formulated. The economic objective is the minimization of the total annual cost of the LPBES and the environmental objective is the minimization of the annual global CO2 emission. The augmented ɛ–constraint method is applied to achieve the Pareto Frontier of the design configuration to reflect the set of solutions representing optimal trade-offs between the economic and environmental objectives. The synthesis and design of the energy system of an airport in north China is studied to test the proposed synthesis and design strategy and the formulated model. Economic optimal scheme and environmental optimal scheme are presented. The Pareto solutions consist of optimal configurations that adapt their operational strategy during a specific range in the Pareto Frontier are presented to show the trade-offs scheme between economic and environmental objectives.