Green Hydrogen
Hydrogen produced by splitting water (electrolysis) using renewable electricity. The process produces zero direct greenhouse gas emissions. Currently costs $4-$8/kg vs. $1-$2/kg for conventional (gray) hydrogen.
Why It Matters
Green hydrogen is considered key to decarbonizing heavy industry (steel, ammonia), long-haul transport, and seasonal energy storage. The IRA's 45V credit ($3/kg) could make it cost-competitive within this decade.
Related Topics
Related Terms
Electrolysis
The process of using electricity to split water (H2O) into hydrogen (H2) and oxygen (O2). The main electrolyzer types are PEM (proton exchange membrane), alkaline, and solid oxide (SOEC).
Gray Hydrogen
Hydrogen produced from natural gas via steam methane reforming (SMR) without capturing the resulting CO2 emissions. This is how 95% of hydrogen is produced today, emitting about 10 kg of CO2 per kg of H2.
Blue Hydrogen
Hydrogen produced from natural gas with carbon capture and storage (CCS) applied to capture 85-95% of the CO2 emissions. Costs between gray and green hydrogen.
45V Tax Credit
The IRA's Clean Hydrogen Production Tax Credit, providing up to $3.00 per kilogram for hydrogen produced with very low lifecycle CO2 emissions (less than 0.45 kg CO2/kg H2). Lower credits available for less-clean production methods.