Optimal Scheduling of Electricity and Water in Renewable-Colocated Desalination Plants

2026-01-05

AI Summary

This study addresses the coordinated scheduling of seawater desalination plants in electricity and water markets under high penetration of renewable energy, proposing a profit-maximizing optimization framework. The flexible desalination plant is modeled as a hybrid resource exhibiting both generation and controllable load characteristics. By jointly coordinating thermal generation, membrane-based desalination loads, and renewable energy sources, the framework optimizes operational strategies across both markets. A novel threshold-based analytical structure is introduced, enabling—for the first time—a closed-form characterization of how technical parameters and electricity prices influence scheduling decisions, thereby achieving efficient and scalable water–energy co-optimization. Numerical simulations demonstrate that the proposed approach significantly outperforms benchmark methods in terms of operational profit, water–electricity interaction efficiency, and system flexibility.

Technology Category

• Search and Optimization: Mixed Discrete/Continuous Search
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Constraint Satisfaction and Optimization: Mixed Discrete/Continuous Optimization

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

We develop a mathematical framework for the optimal scheduling of flexible water desalination plants (WDPs) as hybrid generator-load resources. WDPs integrate thermal generation, membrane-based controllable loads, and renewable energy sources, offering unique operational flexibility for power system operations. They can simultaneously participate in two markets: selling desalinated water to a water utility, and bidirectionally transacting electricity with the grid based on their net electricity demand. We formulate the scheduling decision problem of a profit-maximizing WDP, capturing operational, technological, and market-based coupling between water and electricity flows. The threshold-based structure we derive provides computationally tractable coordination suitable for large-scale deployment, offering operational insights into how thermal generation and membrane-based loads complementarily provide continuous bidirectional flexibility. The thresholds are analytically characterized in closed form as explicit functions of technology and tariff parameters. We examine how small changes in the exogenous tariff and technology parameters affect the WDP's profit. Extensive simulations illustrate the optimal WDP's operation, profit, and water-electricity exchange, demonstrating significant improvements relative to benchmark algorithms.

Problem

• optimal dispatch
• desalination plants
• renewable energy integration
• water-electricity coupling
• hybrid generator-load

Innovation

• optimal dispatch
• desalination plant
• hybrid generator-load
• threshold-based control
• water-electricity coupling