Exploring uncertainty in the household water, energy, and food nexus: trade-offs and synergies in South Africa
Received date: 2025-07-02
Revised date: 2025-09-05
Accepted date: 2026-05-09
Online published: 2026-05-22
Access to water, energy, and food (WEF) remains a persistent challenge in many developing countries, particularly in rural areas where infrastructural limitations and socio-economic vulnerabilities intersect. At the household level, identifying the complex trade-offs and synergies within the water-energy-food (W-E-F) nexus remains a major challenge due to uncertainties and competing priorities. This study addressed this gap by applying partial correlation network analysis and Monte Carlo simulation (MCS) to model the interactions and sensitivities of WEF-related decisions among households. A cross-sectional survey was conducted with 655 households in the Amathole District Municipality (ADM), South Africa, using a mixed sampling approach. The analysis explored key trade-offs and synergies across the food-water (F-W), water-energy (W-E), food-energy (F-E), and W-E-F nexus dimensions. Findings revealed that income competition and transportation were major trade-offs, while solar pump use emerged as a significant synergy. Income competition had the highest node strength (0.872) and expected influence (1.117) in the W-E-F nexus trade-off network. Within the synergy network, the strongest node strength and expected influence were found for transportation (1.380 and 1.106, respectively) in the F-W nexus, good energy infrastructure (0.848 and 1.240, respectively) in the W-E nexus, and low energy cost (1.031 and 1.031, respectively) in the F-E nexus. Simulation results further indicated that income competition was highly sensitive to transportation and labour use, while synergies like solar pump use, good energy infrastructure, and low energy cost were most sensitive to changes in the use of modern energy, water saving technique, and use of modern energy, respectively. The study concluded that household-level WEF decisions were shaped by multidimensional trade-offs and synergies that were highly sensitive to resource access, infrastructure, and income dynamics. This study advanced understanding of household-level uncertainties in the W-E-F nexus and provided empirical evidence to inform policies aimed at strengthening household resilience and promoting sustainable governance.
Thulani NINGI , Amon TARUVINGA , Leocadia ZHOU , Saul NGARAVA . Exploring uncertainty in the household water, energy, and food nexus: trade-offs and synergies in South Africa[J]. Regional Sustainability, 2026 , 7(3) : 100355 . DOI: 10.1016/j.regsus.2026.100355
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