Improving operational flexibility of the integrated pressurized water reactor with the MED-TVC desalination system by control logic systems in the off-design mode

• A dual-purpose nuclear and desalination system was presented. • Thermoflex and Deep software were used for thermodynamic and economic models. • The cogeneration system’s performance was evaluated. • A good agreement was reached on the use of control systems to increase flexibility in the desalination plant . In many regions of the world, nuclear power plants play a vital role as an energy source for freshwater production. They can be coupled with various types of desalination plants to produce electricity and freshwater. In this paper, multi-effect desalination with thermal vapor compression, which is considered the most effective thermal desalination system, has been coupled with a pressurized water reactor. Thermodynamic modeling has been implemented based on energy analysis in the design and off-design modes of Thermoflex software, while economic modeling for freshwater production is conducted using DEEP software. To provide flexibility in freshwater production along with nuclear plant safety, appropriate control systems are incorporated at the design point with a certain degree of flexibility to ensure that variation in the main steam flow rate provides a steady energy source for the desalination system. The performance of the flow control valves was confirmed by applying flow fluctuations of ±30 % to the output steam from the steam generator. The design results showed that producing 15,000 m 3 /day at a cost of 1.232 $/m 3 would reduce only 0.27 % of the net electrical efficiency in the base plant.