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.
Why It Matters
Blue hydrogen is controversial — proponents see it as a bridge to green hydrogen; critics argue upstream methane leakage and imperfect capture make it insufficiently clean.
Related Topics
Related Terms
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.
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.
Carbon Capture and Storage (CCS)
Technologies that capture CO2 emissions from power plants or industrial facilities before they reach the atmosphere, then transport and store the CO2 permanently underground in geological formations.