I regularly hear blue hydrogen (natural gas steam reforming + CCS) emits just as little CO2 as green hydrogen (electrolysis). But you have to include the upstream emissions of natural gas production and then the emissions of blue hydrogen become significantly larger.
This @CEDelft study is one example of many that excludes emissions during methane production. It starts top left but of course the natural gas used doesn't appear out of thin air.
cedelft.eu/en/publication…
cedelft.eu/en/publication…
Still looking for a recent link that calculates the GHG emissions of natural gas production (and to a lesser extend transportation). It should include recent insights using satellite data that shows the leakage is greater than feared. @mzjacobson?
