Skip to main content

Gray hydrogen production produces a significant amount of greenhouse gas emissions

A significant amount of emissions are released into the atmosphere during the production of gray and blue hydrogen. Gray hydrogen is produced through steam methane reforming, which produces CO2 as a direct byproduct. Since gray hydrogen does not use carbon capture, all of the greenhouse gas emissions generated during the production process are released into the atmosphere.1 Emissions are also produced when transporting and storing the methane used in the steam methane reforming process . Studies estimate there are around 11.6 kilograms of CO2 equivalents produced per kilogram of gray hydrogen.2

Sources:​

Footnotes​

  1. Marchant, N. (2021, July 27). Grey, Blue, Green – the Many Colours of Hydrogen Explained. World Economic Forum. https://www.weforum.org/agenda/2021/07/clean-energy-green-hydrogen/. ↩

  2. Bartlett, J. & Krupnick, A. (2020, December). Decarbonized Hydrogen in the US Power and Industrial Sectors: Identifying and Incentivizing Opportunities to Lower Emissions. Resources for the Future. https://media.rff.org/documents/RFF_Report_20-25_Decarbonized_Hydrogen.pdf ↩