Renewable Energy, Vol.156, 14-30, 2020
Thermodynamic and thermo-economic assessment of a hybrid solar/biomass polygeneration system under the semi-arid climate conditions
This paper investigates the thermodynamic and thermo-economic performances of a solar/biomass plant producing the electricity, freshwater, and domestic hot water (DHW) requirements for a 40 households' community. The considered community is located in a semi-arid region (Benguerir, Morocco) characterized by a good solar potential (DNI of 2239 kWh/m(2)/y) and by the presence of brackish groundwater. Compound parabolic collectors and boilers using olive waste residues as feedstock are sequentially combined to drive a 46 kW Organic Rankine Cycle and a reverse osmosis (RO) unit. According to the results, the proposed system is able to meet the community's requirements with an annual biomass consumption of 235 T and a solar share of 11.42%. Results also showed that the monthly plant's overall energy efficiency is in a range between 11.35 and 16.32%, while its corresponding exergy efficiency is between 5.33 and 5.96%. Besides, the achieved electricity, freshwater and, DHW specific costs (respectively 0.231 V/kWh, 0.86 V/m(3) and 0.047 V/kWh) can be considered as competitive in the off-grid context. Finally, the impact of solar field aperture, biomass price, and plant's components investment costs on the plant's economic viability are investigated through parametric and sensitivity analysis. (C) 2020 Elsevier Ltd. All rights reserved.
Keywords:Cogeneration;Desalination;Organic Rankine cycle;Compound parabolic collector;Reverse osmosis;Exergoeconomic