Economic Investigation of Small Scale Cogeneration System in a School Dormitory

The cogeneration system can operate at efficiencies greater than those achieved when heat and power are produced in separate. The optimal system can be determined by selecting the auxiliary system combined with cogeneration system. In the present study, economic investigation has been conducted with the cogeneration electric heat pump (EHP) system and the cogeneration absorption chiller (AC) system to install in the school dormitory. To analyze life cycle cost (LCC), cost items such as initial investment costs, annual energy costs and maintenance costs of each system has been considered. The initial investment cost is referred from the basis of estimated costs, and annual energy costs such as the electric power and gas consumption are based on the data in a school dormitory. LCC is evaluated with the present worth method. Considering investigated results, the initial investment cost of the cogeneration EHP system is more profitable about 28% than the cogeneration AC system. The energy cost of the cogeneration EHP system is more profitable about 8% than the cogeneration AC system. The LCA shows that the cogeneration EHP system is most effective system in the school dormitory.