Performance Assessment of Cogeneration Systems for Industrial District Applications

Abstract

This paper discusses the development and testing of an optimization tool for the energy and economic analysis of cogeneration systems and its application to industrial districts composed by different factories (with electrical, heating and in some cases cooling demand), with time-variable loads and several day-types profiles. The discussion compares three cogeneration systems, respectively based on: (i) a simple cycle gas turbine or (ii) a recuperative cycle gas turbine, both with heat recovery and an absorption chiller, and (iii) an internal combustion engine with electrical chiller units. Test case specifications also include tariff, regulatory and weather conditions, provided that performance of the main components are corrected as a function of load and ambient conditions. The model demonstrates to be really effective in defining the best operating strategy for each cogeneration system; detailed results are presented, in terms of annual energy balances, energy savings compared to separate generation systems (grid losses as well as heat distribution losses are taken into account) and economic analysis. A final parametric analysis is carried out to show the influence on the final results of different assumptions on the combination of fuel prices and electricity tariffs.