Modeling the Energy-Water-Food Nexus: Where Do We Go From Here?

Abstract:

Economic development, population growth, and the changing diets and lifestyles of a growing middle class are expected to lead to increasing demands for water, food, and energy in the future. Meanwhile, climate change may cause localized resource scarcity and exacerbate the supply challenges. Moreover, there is a growing awareness that the supply systems for water, food, and energy are inextricably linked and cannot be evaluated in independent silos. Rather, integrated approaches are needed that can identify the potential trade-offs and synergies among sectors, identify holistic solutions, and evaluate the impacts of socioeconomic and hydroclimatic change. Some initial efforts at modeling the energy-water-food nexus in an integrated fashion have been attempted, but they all suffer from limitations and much more research is needed.

This study provides a review of the current state-of-the-art in modeling the energy-water-food nexus at both global and regional scales, identifies limitations associated with existing approaches, and proposes specific recommendations for improving nexus assessments. Some limitations of existing models include insufficient spatial resolution for assessing water constraints in the energy sector, inadequate representation of the linkages among sectors, limited assessment of the impacts of socioeconomic and hydroclimatic change, limited inclusion of water conveyance, simplistic downscaling of water and energy demands, and the lack of a consistent framework for global nexus assessment. In addition, research gaps are identified by graphically classifying existing nexus assessments according to their spatial resolution, coverage of nexus sectors and linkages, and suitability for assessing the main drivers of global change (e.g., development, urbanization, technology, and climate change). The final portion of the study proposes recommendations for addressing the research gaps and identifies tremendous opportunity for developing better models and assessment tools for informing the design and deployment of future sustainable food, water, and energy supply systems.