The NExus Solutions Tool

The NExus Solutions Tool (NEST) is an open modeling platform that integrates multi-scale energy–water–land resource optimization with distributed hydrological modeling. The approach provides insights into the vulnerability of water, energy and land resources to future socioeconomic and climatic change and how multi-sectoral policies, technological solutions and investments can improve the resilience and sustainability of transformation pathways while avoiding counterproductive interactions among sectors. NEST can be applied at different spatial and temporal resolutions, and is designed specifically to tap into the growing body of open-access geospatial data available through national inventories and the Earth system modeling community. A case study analysis of the Indus River basin in South Asia demonstrates the capability of the model to capture important interlinkages across system transformation pathways towards the United Nations’ Sustainable Development Goals, including the intersections between local and regional transboundary policies and incremental investment costs from rapidly increasing regional consumption projected over the coming decades. The documentation and code for the initial case studies is published by Vinca et al., 2020, and can be found online.

Github repository

Documentation paper:

The NExus Solutions Tool (NEST) v1.0: an open platform for optimizing multi-scale energy–water–land system transformations

A newer version of NEST has been developed, and also referred to as the “MESSAGEix-Nexus” module. This uses the MESSAGEix framework ( see MESSAGEix Workshops ) developed at IIASA and allows the generation of country models with representation of the Energy-water-land system similar to the previously developed NEST model in Vinca et al., 2020. Most of the development is currently under submission and not yet public.

The following presentation introduces the first version of NEST and the MESSAGEix-Nexus module:

  • NEST and MESSAGEix-Nexus module. September 2022, IAMs workshop at the Lahore University of Management Sciences (LUMS) and October 2022 Engage Stakeholder workshop (link to the PURE IIASA database)