Comprehensive sustainability assessment and multi-objective optimization of a novel renewable energy driven multi-energy supply system

Abstract

The pressing challenge of over-reliance on fossil fuels and the resultant greenhouse gas emissions necessitates innovative solutions in the energy sector. Addressing this, our study delves into the design and optimization of a multi-source renewable energy system, distinctively integrating wind, photovoltaic, concentrated solar power, proton exchange membrane electrolyzers, and fuel cells. The system is designed to meet user energy demands while reducing grid power consumption. The approach is novel in its comprehensive energy management strategy, which not only mitigates the inconsistencies of wind and solar energy but also aligns with user demand proactively. To assess the system's sustainability, we employed a life cycle assessment method, encompassing energy, economic, environmental, and social dimensions. A unique aspect of our study is the exploration of how varying meteorological conditions and geographical locations influence the system's sustainability. Key results indicate that, with an increase in photovoltaic capacity from 25 MW to 150 MW, the hybrid system reduces grid power consumption by 18,457.9 MWh annually. This leads to a decrease in the average energy cost by 0.0324$/kWh and an increase in the net present value by 0.2418 M$. Impressively, the system, when integrated with 150 MW of photovoltaic generation, achieves an optimal combined sustainability index of 0.999. Under the best capacity configuration, the levelized cost of energy stands at 0.3096$/kW, with CO2 emissions limited to 630 t/y. A noteworthy correlation emerged: a 1 % decrease in onsite CO2 emissions corresponds to a 1.714 % surge in the levelized cost of energy. This research enhances sustainable energy policy development and decision-making processes by offering a comprehensive understanding of multi-energy supply system sustainability. The results are invaluable for the future design and operation of such systems, facilitating a transition towards more sustainable energy systems.