Technoeconomic assessment of a concentrated solar tower-gas turbine co-generation system

This paper presents a technoeconomic assessment of a solar-driven co-generation system that suits medium/large-scale water production and power generation. The system consists of a concentrated solar tower combined with a gas turbine cycle for power generation and combines reverse osmosis (RO) with multi-effect distillation (MED) for the desalination. Two operational scenarios for the gas turbine exhaust waste heat were assessed for energy efficiency, cost, and environmental impact. The first scenario involves maximizing power generation using organic Rankine cycle operation. The second scenario uses the waste heat from the solar gas turbine cycle to operate the multistage flash (MSF) to produce more water. The co-generation system with the two scenarios were modeled using MATLAB Simulink toolbox. The results reveal that the second scenario yields remarkable results in terms of lower hourly costs (2974 $/h), total water price (0.27 $/m³), and CO₂ emissions (401 tCO₂). MSF has the highest exergy destruction rate (5.632e6 kW), followed by the solar gas turbine cycle (8.843e6 kW). However, RO had the lowest exergy destruction rate (3294 kW), followed by the organic Rankine cycle (1.023e4 kW).