SDG 17 underscores the pivotal and interconnected role of water, including its energy implications, in addressing challenges related to human well-being and sustainable development. Solar water pumps (SWPs) offer an important technological innovation exemplifying this water–energy–food–society nexus. As a comparatively new and eco-friendly approach to irrigation, SWPs have the potential to substantially benefit millions of smallholder farmers in sub-Saharan Africa (SSA). With costs for solar products steadily reducing, the small-scale SWP market is expected to grow in sales and expand into new territories. Overall, the region’s groundwater resources are known to be greatly underutilized and hence enable greater SWP adoption. This study assesses the possible risks to groundwater resources from SWP expansion to the year 2030. The current market environment is extremely heterogeneous across regions and countries. It is conservatively estimated that up to 10,000 units are sold each year, with the strongest markets found in East Africa. Around 100,000 SWP units are estimated to be in operation. For projected rates of annual growth spanning from 6% to 18%, along with intentionally high estimates of groundwater pumping, the upper limit on the quantity of available groundwater pumped by small SWP development to 2030 would vary from 0.4% to 0.6% at the SSA scale. Values in the regions vary from a low of <0.1% for Central Africa through to a high of 1.6%–2.1% for Southern Africa. Specific countries may generally support additional SWPs ranging from tens of thousands up to millions of units without negatively impacting on groundwater availability. Countries characterized by greater recharge and lower current groundwater use can accommodate greater numbers of SWP systems. Short-term threats to the availability of groundwater are assessed to be low over the short and medium terms. Over the long term, risks to groundwater may be greater than evaluated in this study should SWP growth rates exceed the projected range or if improvements in technology allow for stronger, small-capacity pumps to flood the market. To address long-term groundwater management challenges, key action areas have been defined that recognize the diverse conditions across the regions.

There is a need to address resource security and distributional justice in developing countries. People need water, energy, and food to sustain their livelihoods, grow economies, and achieve sustainable development. The interactions between these resource sectors form the crux of water-energy-food (WEF) nexus assessments. In this study, we have utilised the WEF Nexus Index to analyse the WEF nexus of 54 African nations. The results from the analysis were used to illustrate the opportunities and constraints for future development. Generally, African countries are performing sub-optimally in the WEF Nexus Index due to the insecurity of water, energy and/or food. The performance of countries varies with context, highlighting the need for contextual analysis in identifying challenges and potential solutions. Implementation of interventions for achieving WEF security needs to be planned from an integrated perspective to optimise synergies and minimize trade-offs. Implementation of the WEF nexus approach towards simultaneous security of WEF resources has potential to improve the WEF nexus. For example and for many African countries, policies that undergird investments in energy supply projects are needed to unlock available freshwater resources and meet food requirements—energy is shown to be a critical enabler of development. Such projects can be utilised to enhance the ability of farmers to manage water through drought-proofing rainfed agriculture, an increase in irrigation development, or both. WEF nexus-based studies, policies, and projects must be focused on the direct and indirect achievement of SDGs 1, 2, 6, 7, and 13, both in terms of access and availability, to ensure distributional justice, especially in the African context. Such actions, combined with broad public participation, can have a ripple effect on other SDGs such as SDGs 5, 10, and 17, thereby reducing inequalities and building partnerships to attain these aspirational goals. The assessment of Africa’s relatively low scores in terms of the WEF Nexus Index does not represent a negative narrative. Instead, it provides an entry point to identifying hotspots and understanding the underlying challenges, through which more detailed analyses can lead to identified solutions and policies. Many African countries are trapped in an environment that could be termed a ‘poverty-unemployment-inequality nexus’ (due to the interlinkages that exist between these ‘wicked’ problems). The WEF Nexus Index provides high-level insights into these opportunities.

Sustainable and integrated management of water, energy, food, and ecosystems requires a coordinated and cross-sectoral approach to manage trade-offs and maximize synergies among these deeply interconnected resources. This line of action is called the water-energy-food-ecosystem (WEFE) nexus approach. This 5-day course provides an overview of WEFE nexus concepts, issues, and approaches to develop the capacities of early- to mid-career professionals in any WEFE or WEFE-adjacent sector, to foster the integrated, equitable, and sustainable management of WEFE resources. This course was co-developed under the umbrella of the CGIAR Initiative on NEXUS Gains by the Center for Water Resources Studies (CWRS), Institute of Engineering, Tribhuvan University, in partnership with the Alliance of Bioversity international and CIAT, and the International Water Management Institute (IWMI). It includes theory as well as practical applications and interactive elements.

The study reviewed the applications of the water–energy–food (WEF) nexus for knowledge generation and decision-making in the Global South. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol identified 336 studies from the Web of Science and Scopus datasets. One hundred eighty-five articles applied WEF nexus tools to improve the understanding of WEF nexus interactions and to show the potential of nexus applications. The other articles (151) focused on nexus applications to guide planning and decision support for resource allocation and policy formulation. Environment, climate, ecosystems, land, and socioeconomics were other popular nexus dimensions, while waste and economy were considered to a lesser extent. Limitations associated with nexus applications included unavailability of data, uncertainties from data sources, scale mismatch and bias. The inability of nexus tools to capture the complex realities of WEF interactions is hindering adoption, especially for policy formulations and investment planning. Data limitations could be solved using a sound scientific basis to correct uncertainties and substitute unavailable data. Data gaps can be bridged by engaging stakeholders, who can provide local and indigenous knowledge. Despite the limitations, applying nexus tools could be useful in guiding resource management. Limitations associated with nexus applications included – investment planning. Plausible pathways for operationalising the WEF nexus are discussed.

Depleting groundwater resources and increasing energy demand with the huge dependence of India’s agriculture on groundwater and energy, and especially in water deficit rice-based production systems, are posing a serious threat to sustained food, water, and energy security. Sustainability concerns of water, energy, and input-intensive rice-based crop production systems have increased the realization for developing and scaling up alternative agro-techniques that can significantly reduce the water and energy requirements in crop production without compromising on crop yield. The interconnectedness between water, energy, and food makes the concept of water, energy, and food (WEF) nexus more relevant to explore integrated solutions to efficient use of limited and/or declining water and energy resources. Conservation agriculture (CA) is gaining currency as an alternate system for rice/cereal-based production systems to conserve water and energy, improve soil health, reduce cost of cultivation, and preserve ecology. This paper explores the concept of WEF nexus and how CA addresses the challenge of harmonizing the synergy among water, energy, and food though WEF ‘nexus gains’ especially in the context of groundwater irrigated rice/cereal based cropping systems.

Sustainable and integrated management of water, energy, food, and ecosystems requires a coordinated and cross-sectoral approach to manage trade-offs and maximize synergies among these deeply interconnected resources. This line of thinking and action is called the water-energy-food-ecosystem (WEFE) nexus approach. This academic course provides an overview of WEFE nexus concepts, issues, and approaches to develop the capacities of graduate students studying in any WEFE or WEFE-adjacent sector. The aim is to prepare future leaders in this area to foster the integrated, equitable, and sustainable management of WEFE resources. This course was co-developed under the umbrella of the CGIAR Initiative on NEXUS Gains by the Center for Water Resources Studies (CWRS), Institute of Engineering, Tribhuvan University, in partnership with the Alliance of Bioversity International and CIAT, and the International Water Management Institute (IWMI). It includes theory as well as practical applications and interactive elements.

In less than one year the Niger Basin Authority, an intergovernmental body tasked with the sustainable development of the Niger waters and associated resources, passed the first ever nexus policy in a transboundary river basin, contributing to a true acceleration of change for improved water and associated development in the Niger River Basin. The guidelines were developed in close collaboration with the nine basin countries and complemented by a large capacity building program. Using the guidelines can reduce the threat of adverse impacts on the Basin’s shared water and land resources and save millions of dollars of investment funds, while meeting various Shared Vision objectives. Doing so can also help strengthen positive impacts, reduce crosssectoral constraints of single-sector solutions, and identify multisector solutions. Application of the nexus guidelines will increase the efficiency of natural resources use and support implementation and monitoring of (multipurpose) investments. If this can be achieved, the River of Rivers—thought to be the original meaning of the name Niger—will continue to enhance water, food and energy security, and environmental sustainability for generations to come. To support the application of the guidelines, the study team developed an online, simplified nexus assessment tool that is summarized in Appendix 4.

This report presents the main findings of the Nexus assessment study for Sudan. It identified Water-Energy-Food Nexus priority issues in Sudan, suggested operational guidance to align national strategies, policies and implementation plans within a national Nexus framework, identified opportunities to apply the Nexus approach, including institutional settings and capacity building needs, and suggested a series of Water-Energy-Food Nexus projects in Sudan.

In less than one year the Niger Basin Authority, an intergovernmental body tasked with the sustainable development of the Niger waters and associated resources, passed the first ever nexus policy in a transboundary river basin, contributing to a true acceleration of change for improved water and associated development in the Niger River Basin. The guidelines were developed in close collaboration with the nine basin countries and complemented by a large capacity building program. Using the guidelines can reduce the threat of adverse impacts on the Basin’s shared water and land resources and save millions of dollars of investment funds, while meeting various Shared Vision objectives. Doing so can also help strengthen positive impacts, reduce crosssectoral constraints of single-sector solutions, and identify multisector solutions. Application of the nexus guidelines will increase the efficiency of natural resources use and support implementation and monitoring of (multipurpose) investments. If this can be achieved, the River of Rivers—thought to be the original meaning of the name Niger—will continue to enhance water, food and energy security, and environmental sustainability for generations to come. To support the application of the guidelines, the study team developed an online, simplified nexus assessment tool that is summarized in Appendix 4. | Non-PR | IFPRI5; DCA; Capacity Strengthening; 1 Fostering Climate-Resilient and Sustainable Food Supply; 5 Strengthening Institutions and Governance | Natural Resources and Resilience (NRR); Transformation Strategies