Techno-economic analysis of H2 energy storage system based on renewable energy certificate

Abstract

A techno-economic analysis (TEA) was conducted to evaluate the economic profitability and feasibility for a H2 energy storage system using an alkaline and a polymer electrolyte membrane water electrolysis for 1 MW water electrolysis operation. Many economic analysis methods such as itemized cost estimation, profitability analysis using a cumulative cash flow diagram, and uncertainty analysis employing a Monte-Carlo simulation method were utilized to perform a TEA. In particular, a renewable energy certificate (REC) was considered as an additional benefit of a renewable energy use. From itemized cost estimation, respective levelized costs of H2 of 7.21 and 9.19 $ kgH2−1 were obtained for both H2 energy storage systems in an alkaline and a polymer electrolyte membrane water electrolysis by considering current economy situation and therefore it is still difficult to be cost-competitive compared to a commercial H2 production cost. From profitability and uncertainty analysis results, an appropriate REC weight was confirmed in terms of discounted profitability criteria like a discounted payback period, a net present value, a present value ratio, and a discounted cash flow rate of return. In addition, a REC weight was affected on a net present value compared to a REC trading cost fluctuation.