Environmental Impact Analysis of Green, Blue, Turquoise, and Grey Hydrogen Production Pathways

Environmental Impact Analysis of Green, Blue, Turquoise, and Grey Hydrogen Production Pathways

This study analyzes the environmental impacts of different hydrogen production methods, focusing on their potential contribution to climate change mitigation and other environmental considerations.

Grey hydrogen, produced through steam methane reforming (SMR), is the most common method but carries the highest climate change impact due to significant CO2 emissions.

Turquoise hydrogen, produced via methane pyrolysis (MP), offers a lower-carbon alternative, particularly if the carbon byproduct is utilized effectively. However, implementing MP could lead to increased impacts in other environmental categories, highlighting a potential for burden shifting.

Blue hydrogen, produced through SMR with carbon capture and storage (SMR-CCS), demonstrates higher technological maturity compared to MP. It offers a lower climate change impact than grey hydrogen and a less significant increase in other impact categories. As such, SMR-CCS could serve as a crucial bridging technology towards a hydrogen economy.

Green hydrogen, produced via electrolysis powered by renewable energy sources (PEMEL), emerges as the most sustainable long-term solution, with the lowest climate change impact. However, challenges related to increasing water demand and the scarcity of certain materials need to be addressed to ensure the feasibility of widespread green hydrogen infrastructure. Additionally, shifting to green hydrogen production could still result in increased impacts in other environmental areas, emphasizing the need for comprehensive life cycle assessments.

Key Findings:

• Grey hydrogen production (SMR) has the most significant climate change impact.* Turquoise hydrogen (MP) offers a lower-carbon alternative but may increase impacts in other environmental areas.* Blue hydrogen (SMR-CCS) presents a technologically mature bridging option with lower environmental impacts than grey hydrogen.* Green hydrogen (PEMEL) is the most sustainable long-term solution but requires addressing water consumption and material scarcity concerns.* All hydrogen production pathways require careful consideration of potential burden shifting to ensure overall environmental sustainability.

This analysis highlights the importance of considering the full environmental footprint of different hydrogen production pathways to guide policy decisions and technology development towards a truly sustainable hydrogen economy.