NG price

$/MMBtu

Power price

$/MWh

Renewable grid CI

g/kWh

US grid CI

g/kWh

Nuclear CI

g/kWh

Upstream CH₄ leak

GWP CH₄

—

Turquoise C credit

$/tCO₂

Hydrogen color classes: grey/blue/green/pink/turquoise pathway comparison with CI and LCOH, plus the role of methane leakage in blue H₂.

Grey: SMR η=75% no CCUS — typical 9-11 kg CO₂/kg H₂.
Blue: SMR + 90% CCUS — typical 1-3 kg/kg (Howarth concern: leakage matters).
Green: PEM 52 kWh/kg @ renewable grid (50 g/kWh).
Pink: PEM 50 kWh/kg @ nuclear (12 g/kWh).
Turquoise: CH₄ pyrolysis 5 kg CH₄ + 14 kWh/kg → 3.75 kg solid C/kg H₂ (sequestration).
Standards: ISO 14687, CertifHy, IEA Future of Hydrogen, IRENA, Howarth 2021, IRS 45V.

H₂ Color-Class Comparison

Color Comparison