A Biomass-Based Polygeneration System for Historical Building: An Energy Analysis

Combined cooling, heating, and power systems (CCHP) are considered one of the most efficient energy systems since they have a less detrimental environmental impact, and therefore sustainable energy savings, and eventually less CO2 emissions. An even higher advantage is possible when a renewable energy fuel source (e.g., Biomass) is used. The proposed study presents the energy modeling of a 100 kWe capacity, biomass-based CCHP system retrofitted to a historical building, located in Perugia, Italy. Two well-known simulation software’s, ASPEN Plus and TRNSYS, are purposely integrated. In the first phase of the study, a wood biomass combustion-based externally fired gas turbine is modeled in Aspen Plus. In the later phase, a historical building “Sant’ Apollinare” model, and the remaining CCHP system are developed in TRNSYS. The transient system is modeled such that it fulfills the peak heating and cooling demand of the retrofitted building. The main components of the system are: a heat exchanger, storage tanks, a single-stage LiBr-H2O absorption chiller, and balance of plant components. A heat exchanger recovers heat from the gas cycle, which is then utilized for heating and cooling of the end-user building, biomass drying, and domestic hot water (DHW) supply. A storage tank supplies direct heat to the end-user in winters and drives the absorption chiller in summer. The results of the model provide data on the performance parameters of different components of the CCHP system such as temperature, power consumption, and energy profiles that allow evaluating the overall energy performance of the CCHP system.