The Optimal Operational Planning of a Cogeneration System With Storage

The introduction of distributed cogeneration system represents of significant economical and environmental benefits.However,planning of the energy system needs laborious tasks when considering the long term equilibrium between energy demand and supply.The system operational planning of a cogeneration system composed of a gas-steam combined cycle,an absorption chiller,a compressed chiller,and a cold storage was investigated under the "time of use" electric rate structure.Adopting the outer approximation algorithm to solve the optimum problem,while taking the daily total income as the objective function to be maximized,the optimal plant operational policy was determined based on the precondition of fulfilling the cooling demand requirements.The effects of the use of cold storage on the operational policy and economic characteristic were also investigated.The computational results of an example indicate that,under the "time of use" electric rate structure,using the cold storage enhances the system flexibility and shows economic advantage.The validity and effectiveness of the proposed method are also verified.