Optimal Design and Operation of Flexible Energy Polygeneration Systems

The optimal design and operation of flexible polygeneration systems using coal and biomass to coproduce power, liquid fuels, and chemicals is studied. In flexible systems, the various product rates change throughout the lifetime of the plant in response to market conditions in different scenarios. A two-stage programming formulation is proposed to optimize simultaneously the design decision variables and the operational decision variables in all scenarios. The optimal product portfolios, equipment capacity usages, and CO2 emissions of flexible polygeneration systems under different market conditions are discussed. In general, flexible polygeneration systems achieve higher net present values than static ones for the same oil price and carbon tax. Higher net present values can be obtained with increasing operational flexibility.