Orange hydrogen is the new green

• Published in: Nature geoscience 2022-10, Vol.15 (10), p.765-769
• Main Authors: Osselin, F., Soulaine, C., Fauguerolles, C., Gaucher, E. C., Scaillet, B., Pichavant, M.
• Format: Article
• Language: English
• Subjects: 704/106; 704/106/694/682; 704/2151/209; Carbon; Carbon sequestration; Clean energy; Climate change; Coal; Decarbonization; Earth and Environmental Science; Earth Sciences; Earth System Sciences; Electrolysis; Energy; Energy transition; Exploitation; Geochemistry; Geology; Geophysics/Geodesy; Global warming; Green hydrogen; Hydrogen; Hydrogen production; Hydrogen-based energy; Natural gas; Paris Agreement; Perspective; Raw materials; Reforming; Renewable energy; Sciences of the Universe; Transportation systems; Water injection
• ISSN: 1752-0894; 1752-0908
• DOI: 10.1038/s41561-022-01043-9

Maintaining global warming well below 2 °C, as stipulated in the Paris Agreement, will require a complete overhaul of the world energy system. Hydrogen is considered to be a key component of the decarbonization strategy for large parts of the transport system, as well as some heavy industries. Today, about 96% of current hydrogen production comes from the steam reforming of coal or natural gas (labelled black and grey hydrogen, respectively). If hydrogen is to become a solution, then black and grey hydrogen need to be replaced by a low-carbon option. One method that has received much attention is to produce so-called green hydrogen by coupling water electrolysis with renewable energies. However, green hydrogen is expensive and energy-intensive to produce. Here, we explore an alternative option and highlight the benefits of rock-based hydrogen (white and orange) compared with classic electrolysis-based technologies. We show that the exploitation of native hydrogen and its combination with carbon sequestration has the potential to fuel a large part of the energy transition without the substantial energy and raw material cost of green hydrogen. Enhancing natural subsurface hydrogen production through water injection could make a substantial contribution to achieving the low-carbon energy transition that is required to limit global warming.