Economic and environmental analysis for PEM water electrolysis based on replacement moment and renewable electricity resources

Abstract

An environmental issue such as global warming causing series of disasters has been considered as a serious matter, which asks global cooperation, leading the Paris Agreement. As a result, considerable attention has been paid to H-2 due to utilization and storage of renewable electricity expected to increase as time passes. A polymer membrane electrolyte (PEM) water electrolysis using renewable electricity generating from bioenergy, geothermal, onshore wind, etc., has been introduced to store electricity in form of H-2. For preparing successful H-2 society, an economic analysis was conducted considering PEM water electrolyzer cell replacement and renewable electricity resources to figure out economic feasibility. In this study, profitability analysis by drawing discounted cash flow diagram and uncertainty analysis using Monte-Carlo simulation based on itemized cost estimation result were carried out. The results presented that replacement preferred to occur at 2.20 V of max voltage of the PEM water electrolysis cell if electricity price is low and degradation rate is high. Furthermore, H-2 selling price has been more influential factor to a net present value (NPV) than renewable electricity price and hydro and onshore wind energies are regarded as promising renewable electricity resources to achieve goal of H-2 production cost. Moreover, CO2 footprint analysis was conducted to provide guidelines on the replacement of PEM water electrolysis in terms of environmental aspect.