(150d) Insight-Based Design of Local Integrated Systems for Food, Energy and Water
The importance of Food-Energy-Water nexus (also referred to as Water-Energy-Food nexus) has been widely recognised by national governmental bodies and international organisations such as the United Nations, for its significance to sustainable development and national security. Though these three sectors are inextricably linked, as actions in one sector have impacts in one or both of the others, these areas have too often been considered individually. Thus, there is a need to look at them from a holistic perspective and develop tools that take into consideration their interdependencies. This opens up opportunities for process system engineering research. As such, the aim of this study is to develop a systematic insight-based approach for the design of an integrated local production system particularly to meet local demands for food, energy and water. One of the benefits of the insight-based approach is that it allows decision variables to remain tractable throughout the design process. Unlike mathematical optimisation approaches, intermediate results from insight-based approaches can be analysed, interpreted and used to inform the implications of a given design for the operation of the whole system, thus offering a more practical tool for decision-makers and local planners to use. Insight-based approaches which include techniques such as pinch analysis for heat integration and mass integration have proved particularly useful for the integration of energy and material streams in industrial production processes within eco-industrial parks and industrial symbiosis systems. They have been successfully implemented for enhancing resource efficiency and sustainability of processes involving heat, water and hydrogen, to name a few applications. Although the proposed study also pursues higher resource efficiencies through integration of resources, the design of the local integrated production system has a distinctive emphasis on local resources and demands and on the holistic consideration of all types of agricultural, industrial and municipal processes to take place at the locality of concern. This work will combine existing methods and adapt them to enable the identification of the efficient use of various locally available resources. A net gain indicator will be defined to quantify the avoided cumulative effort that would have been spent for importing resources to satisfy the demand. Using the net gain indicator, parallel processing and utilisation options within and between different subsystems can be compared and the optimal actions identified. The proposed insight-based approach for the design of local integrated system of food, energy and water will be illustrated through a case study based on an eco-town in the UK.