Advancements in hydrogen energy systems : a review of levelized costs, financial incentives and technological innovations

Hydrogen energy systems (HES) are increasingly recognized as pivotal in cutting global carbon dioxide (CO2) emissions, especially in transportation, power generation, and industrial sectors. This paper offers a comprehensive review of HES, emphasizing their diverse applications and economic viability. By 2030, hydrogen energy is expected to revolutionize various sectors, significantly impacting CO2 abatement and energy demand. In electricity and power generation, hydrogen could reduce CO2 emissions by 50-100 million tons annually, requiring 10-20 million tons of hydrogen and an investment of $50-100 billion, underscoring its role in grid stabilization. Additionally, in the heating sector, hydrogen could facilitate a CO2 abatement of 30-50 million tons. We examine the levelized cost of hydrogen (LCOH) production, influenced by factors like production methods, efficiency, and infrastructure. While steam methane reforming is cost-effective, it poses a larger environmental impact compared to electrolysis. The global life-cycle cost of hydrogen production decreases as production scales up, with current costs ranging from $1-3 per kg for fossil-based sources to $3.4-7.5 per kg for electrolysis using low-emission electricity. These costs are projected to decrease, especially for electrolytic hydrogen in regions with abundant solar energy. However, despite the technical feasibility of decarbonization, high production costs still pose challenges. A systematic and effective transition to a hydrogen economy requires comprehensive policy and financial support mechanisms, including incentives, subsidies, tax measures, and funding for research and development of pilot projects. Additionally, the paper discusses hydrogen's role in advanced storage technologies such as hydrides and Japan's ENE-FARM solution for residential energy, emphasizing the need for strategic investments across the hydrogen value chain to enhance HES competitiveness, reduce LCOH, and advance the learning rates of hydrogen production technologies.