Simulation and comprehensive 4E study of a high-efficient CCHP arrangement utilizing geothermal energy and eco-friendly heat recovery

Abstract

In recent years, geothermal energy has received significant attention as it provides a sustainable and renewable energy resource for various applications. The primary objective of this study is to manage the relative irreversibility and enhance productivity through efficient utilization of geothermal energy. The present paper establishes a high-efficiency and environmentally sustainable heat integration model in a novel configuration to be a geothermal energy source having the ability to produce power, heat, and cooling. The proposed framework consists of a Kalina cycle, two organic Rankine cycles, an ammonia Rankine cycle, a single-flash power unit, and a combined cooling and power unit. The simulation of the proposed system is implemented within the Aspen HYSYS software, with an examination of its feasibility across energy, exergy, economic, and environmental considerations. The research findings indicate that the system can generate 23250.8 kW of power, 582.1 kg/s of hot water, and 2.812 kg/s of chilled water. Therefore, the total exergy destruction rate is 14104 kW, with the Kalina cycle accounting for the majority share at 40.47 % Moreover, the energy and energy efficiencies of the suggested structure are 61.81 % and 72.52 %, respectively. The environmental analysis indicates that the entire process lacks carbon dioxide emissions. Furthermore, the economic analysis reveals that the total unit exergy cost and levelized cost of energy are determined to be 5.13 $/GJ and 0.511 $/kWh, respectively. Also, the proposed system exhibits a favorable net present value of approximately 32.16 M$. Hence, the project demonstrates profitability.