Optimization of Water Grid at Macroscopic Level Analyzing Water-Energy-Food Nexus

Water, energy, and food are essential for human well-being and for sustainable development. Water is required in almost all types of electricity generation and it is highly consumed in food production. Cities, industry, and crop production have increased their needs for water, energy and land resources, and at the same time, they are facing problems associated with the environmental degradation and, in some regions, resource scarcity. This paper proposes a multiobjective optimization model for the design of a water distribution network from a water-energy-food nexus point of view. Additionally, crop production and cost relationships are integrated to account for the water and energy requirements in the agricultural sector. The economic objective is the maximization of annual gross profit, which accounts for the water, energy and food production; the environmental objective establishes the minimization of overall greenhouse gas emissions, and the social objective is the maximization of the number of jobs. In this paper, because the objectives are opposites, a multistakeholder assessment is proposed in order to analyze and quantify the relationship of the water-energy-food nexus to assess synergies that improve the decision-making process. The mathematical model was applied to a case study located in the Sonoran Desert in Mexico, in which, a series of scenarios were solved to illustrate the capabilities of the proposed optimization approach. The results show strong trade-offs between the considered objectives as well as the quantification of the water-energy-food nexus.