Parametric analysis of a power-water cogeneration system based on single-extraction organic Rankine cycle

Highlights: • A novel power-water cogeneration system with single-extracted ORC is proposed. • Energy analysis of the proposed cogeneration system is achieved. • Influences from the extraction parameters are investigated. • Performance comparison between the current and no extraction systems is achieved. -- Abstract: In this paper, a novel power-water cogeneration system, with a single-extraction organic Rankine cycle (ORC) as the top cycle, is proposed and constituted. Extraction vapor from the turbine in the ORC is designed to power the water-heated humidification dehumidification (HDH) desalination unit. Based on the distribution of the flow streams, equations of mass and energy conservation are built, and then thermodynamic performance of the power-water cogeneration system is simulated at the designated conditions. Furthermore, the influences from the extraction parameters on the performance of the proposed cogeneration system are also revealed. The net power, water production and total efficiency of the cogeneration system arrive at 15.74 kW, 76.88 kgh⁻¹ and 40.81%, respectively. During the influence analysis from the extraction parameters, it is found that variation of extraction ratio is contradictory for improving the power generation and water production, while a lower extraction pressure is always beneficial. However, the extraction parameters are effective to regulate the distribution between the generated power and water within the cogeneration system.