The need to quantitatively measure the security of the water–energy–food (WEF) nexus sectors in a region is of great importance due to the vulnerability of each sector and the associated cost. This paper presents an approach for optimizing the security indices of the WEF nexus by analyzing the availability, accessibility, and sustainability of water, energy, and food resources. To maximize the security indices, a multi-objective mixed integer nonlinear programing model involving multiple stakeholders is presented. Through the model, the dependent variables for the optimization of the indices are described, and these in turn represent new and existing technologies considering the economic and environmental aspects. Furthermore, the optimization model results in different configurations when selecting technologies to satisfy high demands imposed by the population, maximizing the value of the evaluated indices, and improving the performance of the distribution network of the studied area. Different scenarios are designed to observe the behavior of the objective functions (minimizing the total annual cost, fresh water consumption, and greenhouse gas emissions) while maximizing the security of the WEF nexus; the indices are illustrated in radar graphs that allow identifying the interactions between the involved sectors. A case study of an area of Mexico with great development is analyzed due to its economic importance; however, the model is applicable to any region with the corresponding data and similar climatic characteristics. The results show the vulnerability of the distribution network and that it is possible to satisfy the demands of a region with the implementation of new policies that allow maximizing the values of the WEF nexus security indices. In general, the total annual cost and greenhouse gas emissions are dependent on the variations in the indices, and the indices associated with the energy sector fluctuate more in the analyzed scenarios.

Thoroughly understanding the security of water, energy and food (WEF) and the factors that influence them is essential for sustainable development management in any region. This study proposed a new analytical framework for WEF security evaluation in both individual sectors and the whole system, using the technique for order preference by similarity to an ideal solution (TOPSIS) and four dimensions of security indicators: availability, self-sufficiency, productivity and accessibility. The internal relationships among the three sectors and the main factors influencing WEF security were analysed by Spearman’s rank correlation and radar graphs, respectively. The five countries in Central Asia (CA), which are experiencing WEF crises and facing great challenges in achieving their sustainable development goals (SDGs), were chosen as a case study in this paper. Our results showed that Kazakhstan attained the highest WEF security level, followed by Kyrgyzstan, Turkmenistan and Uzbekistan; Tajikistan exhibited the lowest security level from 2000 to 2014. Three types of internal relationships among the three sectors were identified: synergies, trade-offs and unclassified. The unclassified relationship type accounted for the largest share of 54% in CA, suggesting great potential for synergetic improvement among the three sectors. Approaches for improving the country WEF security based on our research are as follows: Kazakhstan should prioritize food allocation and supply, Kyrgyzstan and Tajikistan should increase energy and food production and raise the supply level and usage efficiency of water and food, Turkmenistan should increase the available water resources and food production and improve the supply level and usage efficiency of water and energy, and Uzbekistan should both increase the available amount and enhance the WEF management performance.