Optimising the energy-water-CO₂ nexus of a water distribution network

The digital age attracts significant challenges in the delivery of fourth industrial revolution (4IR) based technologies. The energy-water-CO₂ nexus benefits of 4IR technologies are a significantly greater challenge, especially across the water distribution network (WDN). A business process based energy-water-CO₂ nexus model was developed with the capacity to comprehensively simulate a WDN, and predict the impact of 4IR technologies on the energy-water-CO₂ nexus. The model was applied to the monitoring and control business process of a local water utilities water distribution network. The model simulates the baseline (as-is) energy-water-CO₂ nexus, and evaluates the impact of the adoption of variable speed drive (VSD) and the internet of things (IoT) based on three operational regimes: normal operating pressure, low pressure and high pressure. The model evaluates VSD and IoT adoption singly and in-combination. The VSD has the largest positive impact on the energy-water-CO₂ nexus, reducing the energy demand and CO₂ emissions by16% each, and the water losses by 22%. A reduction in water losses, results in an increase in revenue for the water utility enabling the upgrading of aging infrastructure, investment in digital technologies and the expansion of infrastructure to increase access to clean drinking water. Whilst the impact of IoT on the WDN water-energy-CO₂ nexus is low, it is critical towards developing a “smart” and “self-adjusting” water distribution network.