The climate benefit of a greener blue hydrogen

Previous studies have demonstrated the potential benefit of a future hydrogen economy in terms of reducing CO₂ emissions. The hydrogen leakage rate and the green hydrogen fraction in the mix were identified as key factors in maximising the climate benefit of this energy transition. This study highlights the importance of blue hydrogen production hypotheses for a climate-beneficial transition to a hydrogen economy. The benefits are substantial when blue hydrogen is produced properly using an efficient CO₂ sequestration hydrogen production plant and minimizing the rate of upstream CH₄ leakage. The rate of hydrogen leakage remains an important parameter to consider throughout the entire value chain. Based on various scenarios of the development of a 21st century hydrogen economy, we estimate significant CO₂ emission reductions of 266-418 GtCO₂eq (up to 395-675 GtCO₂eq in the case of a "high hydrogen demand" scenario) between 2030 and 2100. This cumulative reduction in CO₂ emissions translates into a reduction in global warming of 0.12-0.19 °C (0.18-0.30 °C for a "high hydrogen demand") by the end of the century.