Sep 17, 2023
120 million tons of hydrogen a year, mostly from natural gas via steam reformation creating 8 tons CO2 per ton of hydrogen. More from oil with higher CO2 output. More from coal with even higher CO2 output, 20 to 30 tons CO2 per ton of steel. Upstream methane emissions adding a ton or more of CO2e per ton of hydrogen.
The combination is in the range of 1.5 billion tons of CO2e per year, about 4% of global annual CO2 emissions, and in the same range as aviation.
