Different types ... 1 a kilogram. “Blue” hydrogen also uses fossil fuels but captures and stores the CO2. Blue is about $2 per kilogram at the cheapest. Finally, there is “green” hydrogen ...

This process produces "green hydrogen," which results in no carbon emissions. Green and blue are two of the many colors used to classify hydrogen by its production method and emissions profile.

According to IEEFA, green hydrogen techniques—which involve using renewable energy—may yet be a better option. Blue hydrogen, Basirat says, requires "significant upfront investment" in production ...