A Novel Optimal Operational Strategy for the CCHP System Based on Two Operating Modes

The operating modes directly influence the system performance of combined cooling, heating and power (CCHP) systems. To improve the comprehensive operational performance, in this paper, based on two typical operating modes, i.e., following the electric load (FEL) and following the thermal load (FTL), a novel optimal operational strategy depending on an integrated performance criterion (IPC) is proposed. Using this strategy, the whole operating space of the CCHP system can be divided into several regions by one to three border surfaces determined by energy requirements and the IPC. Then the operating point of the CCHP system is located in a corresponding operating mode region to achieve improved IPC. The IPC simultaneously considers the primary energy consumption, the operational cost and the carbon dioxide emissions. The carbon tax is also included in the operational cost. A hypothetical hotel building is modeled as the reference system to evaluate the proposed strategy. Simulation results show that, for the same CCHP system of the hypothetical hotel, the IPC with the proposed strategy is better than that with the traditional strategy. The proposed strategy can reflect and balance the influences of energy requirements, energy prices and emissions effectively.