(319e) NexSym – a Local Nexus Simulation System

Food, energy and water are essential needs to sustain human life. The complex interactions and interdependencies among the infrastructures and decision making processes involved in the provisioning of such needs have recently generated great debate under the umbrella of the Food-Energy-Water (FEW) nexus (also referred to as Water-Energy-Food nexus). As society becomes increasingly aware that resources available to satisfy the needs of a growing population are finite, there is a call to look at the interactions and start creating more efficient solutions to manage the wide range of nexus scenarios, especially under conditions of climate change, increased urbanisation and waste generation. Furthermore, there is awareness of the importance of maintaining ecosystems to achieve sustainable production while expanding land use and using it more intensively to obtain more food, energy and clean water. The nexus may manifest in unique ways in different localities. Similarly, the global conditions will affect each location differently. Therefore, it is urgent to develop holistic analytical tools that could inform decision making for managing the interdependencies of the FEW nexus at the local scale. This is one of the ways chemical engineers are able to contribute with solutions by applying their skills of modelling processes and managing constraints associated with an interconnected system.

In this work, we present the Local Nexus Simulation System (NexSym) that integrates models for technological process components involved in the production of food, energy and clean water as well as waste treatment. Furthermore, the techno-ecological interactions can be simulated by integrating models for ecosystem processes, including agricultural production. The tool then allows the user to build a â??flowsheetâ? of the local system with the component of interest (e.g. bioenergy production) and their interacting local system components (e.g. biomass cultivation, water provisioning). This enables examination of the whole picture of FEW nexus interactions at the local scale, which can then be investigated within a global context. Options for managing the nexus from an engineering perspective can then be devised and further evaluated under scenarios of interest to the user. The NexSym is expected to have wide application by engineers working across the nexus system components, planners for urban or rural development, policy makers and decision makers in general. The tool will be illustrated with sample case studies featuring interactions between food, energy, water provisioning and waste treatment to demonstrate the usefulness of such a tool in understanding, managing and creating sustainable solutions to the nexus.