Potential analysis of hydrogen energy technology in the power grid based on carbon tax: A case study in Japan

Electrolytic hydrogen storage technology of renewable energy is considered as one of the important measures to realize the high proportion of renewable energy. However, developing this technology has been slow due to the cost. This study proposes highlighting the environmental advantages of renewable power combined with a carbon tax at the national level to expand the application space of hydrogen storage technology. First, the economy and technical characteristics of hydrogen storage technology and conventional energy-storage technology were compared. Then, Japan's top 10 power companies, which account for 90% of the power supply, were taken as the research objects. The proportion of change in renewable power after introducing a carbon tax was studied, taking the weighted minimum of the feed-in tariffs as the optimization objective. The contribution of hydrogen storage technology to the change in renewable power share was analyzed. Next, a sensitivity analysis was conducted on the fossil energy price and cost of renewable power equipment that affects the research. Finally, the contribution of a carbon tax and hydrogen storage technology to Japan's emission reduction target was calculated and analyzed. The results showed that the characteristics of long-distance transportation of hydrogen energy and making renewable energy have economic advantages under the current carbon tax (5–6 JPY/kg-CO2). The cost of liquified natural gas (LNG) and the investment of photovoltaic (PV) have a significant impact on the weighted minimum feed-in price, which can make the development of hydrogen storage technology no longer rely on the setting of carbon tax. The results obtained in this study provide a theoretical reference for the application of hydrogen storage technology in the high proportion of renewable energy consumption. At the same time, it can also provide data reference for large-scale construction of renewable energy in regions where solar and wind energy resources are not excellent.