Thermoeconomic analysis of a novel configuration of a biomass‐powered organic Rankine cycle for residential application with consideration the effect of battery energy storage

Abstract

In this article, the energy, exergy, and economic analysis of an organic Rankine cycle (ORC) system powered by biogas to provide electricity, heating, and cooling loads for a residential building in Munich city is investigated. Two methods have been proposed to meet the heating and cooling needs of the residential building. In the first method, heating and cooling needs are provided by a heat pump and mechanical refrigeration (System I), and in the second method, these needs are provided by a radiator and absorption refrigeration cycle (System II). In both modes of this system, the effects of battery energy storage (BES) have been analyzed for peak shaving. The working method of this research is that the residential building's electricity, heating, and cooling needs are calculated by Homer and Carrier software, respectively. Engineering equation solver software models the main local power generation system. A new method has been proposed to select the required number of units to meet the needs of the building with and without BES. The results showed that for System I with and without BES, 3 and 1 ORC units with a nominal power of 2 kW can meet all the needs of the building, respectively. In contrast, for System II, the number of 1 unit with 2 kW and 1 unit with 1 kW is needed to meet the energy needs of a residential building with and without BES. It can be concluded that heating and cooling the building with a radiator and absorption chiller cycle is more cost‐effective. The energy and exergy efficiency of ORC is reported as 11.3% and 65.7%, respectively, and the highest exergy destruction rate is related to the heater and boiler. From the economic point of view, the payback period of System II compared with System I is reduced from 18.4 to 5.66 years without using BES. With the use of BES, the payback period is reduced to 5.3 and 5.66 years, respectively. The lowest and highest electricity prices belong to System I with and without BES, which are 3.11 and 0.36 US$/kWh, respectively.