A comparative simulation study of single and hybrid battery energy storage systems for peak reduction and valley filling using norm-2 optimization

The objective of this study is to address the power imbalance between supply and demand caused by the adoption of electric vehicles and renewable energy sources. Due to power imbalance at the point of common coupling, additional peaks and valleys will be created. The novelty of this work lies in proposing a hybrid energy storage system that combines power-dense and energy-dense batteries, optimized using a Norm-2 approach, to mitigate these imbalances effectively. The methodology involves a simulation study using realistic distribution grid load curves, focusing on two case studies. The results of this study reveal that, with an optimally sized energy storage system, power-dense batteries reduce the peak power demand by 15 % and valley filling by 9.8 %, while energy-dense batteries fill the valleys by 15 % and improve the peak power demand by 9.3 %. Furthermore, a hybrid energy storage system outperforms and is useful for multiple grid applications when compared with a single type of energy storage system. The study identifies an optimal capacity share of 40 % power-dense and 60 % energy-dense batteries as providing an effective balance between power and energy requirements. The findings highlight the proposed system successfully manages not only the highest peaks and valleys, but also intermediate fluctuations caused by renewable energy and electric vehicle integration. During a one-year simulation using a hybrid energy storage system, peak power demand decreased by 11 %, peak-to-average ratio improved by 12 %, and power variance was reduced by 29 %, indicating more stable and efficient grid performance compared to without any storage system.