Quantifying and enhancing the energy resilience of zero-emission train station systems against power outages via electrified train-building integrations

Abstract

Addressing power outages due to renewable energy penetration and conventional utility grid issues is vital to ensure the reliability and resilience of any energy system. Therefore, this project begins by modelling a renewable energy-supported swappable battery-powered railway system with stochastically driven power outages. Then, it comprehensively quantified energy resilience using novel technological, economic and environmental indicators for different annual power outage percentages and renewable energy capacities. Two implementations are systematically analysed: one that uses a unique control strategy for dynamically handling the power outage periods in addition to the existing control strategy, and another that finds the right renewable energy mix within and between the stations. The first one improves the autonomous net-zero energy system by enhancing the energy-based resilience factor, annual carbon emissions from the system, and net present value for the estimated lifetime of 20 years from 0.83 to 0.99, 264.7 to 12.7 ton and –7.3 × 106 to 51.4 × 106 HKD, respectively. The second investigation reveals that technological and environmental indicators favour solar energy of 70 %, and the economic indicator prefers more wind energy. Using 100 % wind energy on both stations of the metro railway system is economically consistently effective as it provides a net present value of up to 59.8 × 106 HKD owing to the 30 % lower capital cost of wind energy compared to solar energy.