Optimal design and analysis of CCHP system for a hotel application

Abstract Combined cooling, heating and power (CCHP) system fuelled by natural gas is expected to play an important role in the sustainable energy strategy. The aim of this paper is to describe a natural-gas CCHP system for a hotel located in Dalian (China). In this study, by minimizing the annual total costs (ATC), the capacity and numbers of power generation unit (PGU) is determined. Meanwhile, the application of CCHP system is given to ascertain the relationship between the optimum installed capacities, operation strategy and performance evaluation. The results show that with a single PGU, the trend of ATCS increases firstly with the increasing of the capacity, reaches the maximum value, and then mostly decreases. Furthermore, with two units in parallel, when the major unit capacity is higher than the optimum value, its impact plays a dominant role on the ATCS. However, when the major unit is lower than the optimum value, the impact can be determined by the minor unit. Sensitivity analysis of energy prices is executed, which will affect the capacity of the system and cooling ratio correspondingly. The rise of nature gas price makes the optimal capacity of the system decreased and the cooling ratio increased.