OSiRIS: a dynamic model to link on-site water recovery options to key robustness drivers

ABSTRACT

Screenshot of the OSiRIS interface showing scenario building, a model overview diagram, and a spider plot of six key performance indicators.

On-site water treatment and reuse can drastically lower water consumption down to achieve complete water independence. A rapid and intuitive way of assessing water consumption, water quality, energy needs, and robustness against external factors is missing; for which we developed On-site Water Reuse: Instant Simulator (OSiRIS). This stand-alone tool allows users to define their own scenarios and assess their water robustness with dynamic simulations. As an example, a Belgian household was evaluated over 10 years for nine scenarios with varying degrees of on-site water treatment. ‘Spec sheet’ water treatment characteristics are required by the model, thus broadening usability, with the drawback that in-depth simulation of treatment mechanics is not currently performed. The local water cycle was closed only for extreme decentralization, i.e., no excess water exported and no additional supply needed. Water independence was reached with 76% wastewater reuse. A photovoltaic installation (0.5 kWp, 2 kWh battery) provided 80% of the needed energy for the most energy-intensive scenario, being 260 kWh·p−1·year−1. Though specific to this case in both context (Belgian household, number of inhabitants, and water use behavior) and scenario construction (technologies installed and water reuse choices), these results emphasize the potential for increased water robustness on a single-household level.