Multi-scale decision-making of HRES-powered flexible microreaction electrosynthesis systems

Abstract

The imperative target of net-zero necessitates the energy-intensive chemical industry to adopt massive renewable energy to reduce emissions of greenhouse gases and pollutants. The inherent conflict between the intermittent renewable energy supply and the rigid energy demand of the chemical industry traditionally entails costly investment in excessive storage systems to guarantee operational stability, leading to a drastic increase in production costs. In contrast, we design a flexible microreaction electrosynthesis system (MESS) powered by hybrid renewable energy systems (HRES) to mitigate the rigidity of energy demand and to moderate the reliance on energy storage. Accordingly, a mixed-integer linear programming (MILP) model is introduced for the multi-scale decision-making on the configuration and operating conditions for producing high-value-added organic chemicals under variable solar and onshore wind energy supplies. We demonstrate that investment in energy storage systems can be reduced by up to 66.6% through flexible operations compared to traditional rigid chemical production. Comparisons highlight the rapid start-up and shut-down abilities of microreactors that enable MESS to accommodate renewable energy variability. Furthermore, we identify the main bottlenecks of the integrated MESS-HRES that hinder the overall performance: current densities, Faraday efficiencies and microreactor costs at the unit level, and costs and variations of solar energy at the system level.