Solar driven polygeneration system for power, desalination and cooling

Abstract This paper presents a thermodynamic study of a polygeneration system combining Solar Power System (SPS), Multi Effect Desalination (MED) system and Absorption Refrigeration System (ARS). The plant is powered by solar energy with a backup natural gas heater. SPS includes a parabolic Trough Collector (PTC) field with thermal oil working fluid and steam Rankine cycle. A detailed simulation of a plant that can serve 1000 residential houses is developed. The analysis is performed using MATLAB package and its graphical user interface (GUI) tool. A parametric study is carried out to investigate effects of the different design and operating parameters on the plant energetic and exergetic parameters. Moreover, an economic evaluation is conducted to evaluate CAPEX, OPEX and unit product water/cooling costs. Results reveal that the highest exergy loss was found to occur in PTC solar field with about 82.42% of the plant exergy destruction. Moreover, the minimum PTC area can be achieved through the selection of the units (ARS, MED and SPS) capacities depending on steam condenser flow rate. In addition, the highest OPEX and total costs percentage (87.68% and 54.83%) are due to the natural gas heater. The proposed integrated system provides the lowest unit water price (1.247 $/m3), unit cooling price (0.003 $/kW hr) and the highest exergetic efficiency (23.95%) compared to the single and dual-purpose ARS/MED systems.