Techno-economic analysis of Hydrogen integration as a natural gas replacement in steel mill production processes

This thesis explores the potential of utilizing hydrogen as an energy carrier to partially replace natural gas in steel production processes. The developed tool, based on the current annual natural gas consumption, facility operating hours, and the percentage of hydrogen to be blended with natural gas, creates a model to assess the investment’s viability from both economic and environmental perspectives. The hydrogen used is green, produced via an electrolyzer powered either by electricity from a photovoltaic plant, also modeled in this tool, or from the grid with emissions neutralized through guarantees of origin. The model results indicate that, at present, the investment is not yet economically feasible, primarily due to the high upfront costs, particularly those associated with the electrolyzer. However, it is expected to become more viable in the coming years as per the projected price forecasts. Furthermore, the Life Cycle Assessment study shows that natural gas has not a major impact on overall emissions during steel production, with the largest contributors being electricity consumption, if the national production mix is considered, and raw material supply. Although the contribution may not be the most significant, reducing the impact of this process to zero is still essential for achieving zero-emission production. Hydrogen offers an effective solution for reducing emissions in areas where electrification alone is either not feasible or less efficient. While it may not achieve carbon neutrality on its own, hydrogen plays a key role in complementing electricity and emerging technologies, facilitating the transition from fossil fuels to renewable energy, especially in hard-to-abate sectors.