Performance and environmental impact assessment of a geothermal-assisted combined plant for multi-generation products

Abstract

In this research work, a newly designed geothermal energy-supported integrated plant for heating, cooling, power, hot water, and hydrogen generation is proposed. The modeled system has two organic Rankine cycles (ORCs), ORC-1 working with n-pentane, and ORC-2 working with n-butane. Besides, this study also consists of an absorption cooling cycle, which is operated lithium bromide-water, and a Proton Exchange Membrane electrolyzer. In this framework, thermodynamic and environmental impact analyses are made to define the performance of the examined plant and lessening the greenhouse gas emission. Furthermore, an environmental impact evaluation is made to define the effect of greenhouse gases, as a result of the use of non-renewable energy-based fuels to meet the production of power from the suggested model. Analysis results displayed that the total energy and exergy performances of the examined system are computed to be 63.28% and 55.99%, respectively. Sub-plants of the system modeled, ORC-1 and ORC-2 have 22.31% and 25.18% energy efficiency. The heating load, cooling load, and hydrogen generation rate are found as 806.4 kW, 758 kW, and 9.0036 kg/h, respectively. Also, the modeled cycle saves about annual 26421 t CO2 gas emission if the coal is used as fuel in the plant for power generation.