Infrastructure Expansion Planning Under Food-Energy-Water Nexus Considerations

Due to global population growth, economic development, and urbanization, the demands for food, energy, and fresh water are rapidly increasing, exerting pressures on existing supply chains and urban infrastructure. These pressures are exacerbated by climate change impacts and delayed policy response. As these demands grow, the stresses and interdependences between these resources become more apparent. A holistic approach for the optimal decision-making for energy and water infrastructure planning that build on a Food-Energy-Water Nexus (FEW-N) framework is essential to meet the increasing utility demands. Such a decision-making approach is complex and involves challenges related to: (i) involvement of different stakeholders with often conflicting objectives, (ii) the intrinsic intermittent nature of renewable energy sources; and (iii) stochastic energy and water demand profiles.

In this work, we present a novel FEW-N superstructure-based representation and multi-objective optimization framework for energy and water infrastructure planning. The FEW-N problem is posed as a two-stage stochastic mixed-integer linear program that minimizes the capital expenditures, operational cost, water usage and land competition of the FEW-N system. Planning decisions taken into consideration include the ability to construct new power plants, energy storage units and water treatment plants, while scheduling decisions involve the operating level of the plants, how the energy is allocated within the system, and when energy is stored and released from storage devices. We illustrate the effectiveness of the infrastructure expansion framework through the use of a case study that spans the ERCOT region of Texas.