Analysis of modeling and performance for PV and energy storage integration in suburban railways

Abstract

The rail sector faces growing pressure to reduce energy consumption and carbon emissions, in line with global sustainability goals. Electrification of rail routes, along with the integration of renewable energy sources (RES), has become critical for enhancing energy efficiency and minimizing emissions. This study explores the integration of photovoltaic (PV) systems and energy storage systems (ESS) into AC railways, focusing on their impact on energy consumption and overall system performance. A mathematical model of the railway system is developed, and two case studies are performed on a standard AC railway route servicing suburban train. The model’s accuracy is validated according to the British Standard EN50641 under both normal and outage conditions, with results generally aligning with reference values, except for a minor deviation observed during outage scenarios. In Case Study 1, an initial examination compares integration at the substation level with integration at the catenary level, aiming to provide insights into various integration locations. The analysis reveals that the lowest daily operational cost is achieved at the substation integration point (0 km). However, integration at the 20 km catenary point achieves a comparable cost reduction, with a decrease of 8.6%, and the cost difference between the two locations is negligible, at only 0.01%. Following this, Case Study 2 investigates how varying capacities of PV and ESS affect energy generation and daily operational costs. The findings indicate that increasing capacities leads to expected reductions in both energy generation and operational costs. Nevertheless, these cost reductions may not be optimal due to the ESS control strategy employed in the study.