Techno-economic feasibility evaluation of a standalone solar-powered alkaline water electrolyzer considering the influence of battery energy storage system: A Korean case study

Hydrogen use is dominated by industry, with most hydrogen demand mitigated using fossil fuels; therefore, there is an eminent potential for the reduction of emissions by replacing fossil-derived hydrogen with a renewable hydrogen source. Although the emission reduction by using renewable energy presents a promising potential, its fluctuating nature is still a challenge to be addressed. In this study, considering a battery energy storage system (BESS), a dynamic operation-based techno-economic evaluation of a standalone solar photovoltaic (PV)-powered alkaline water electrolyzer (AWE) was conducted using actual solar data. Different process configurations were designed and simulated to quantify the available potential of a standalone solar-powered hydrogen production system in Korea. Furthermore, economic evaluation metrics, such as levelized cost of hydrogen (LCOH) and Monte Carlo simulation, were used to assess the potential of different configurations under variable market prices and future technology costs to estimate the future potential. The results showed that Case 1 (standalone solar-powered AWE without BESS) offers the lowest LCOH (9.55 $/kg) but with daytime operation only. Meanwhile, Case 4 (standalone solar-powered AWE with BESS) reported the second-lowest LCOH (11.67 $/kg) compared with the other cases. The results also suggested that systems with BESS can increase operational reliability by minimizing operational fluctuations and maximizing operational hours but with a slightly higher LCOH. The conducted sensitivity analysis showed that the technology cost (solar PV, AWE, and BESS) has the highest impact on LCOH, which is promising, in light of the decreasing trend in the future costs of such technologies.