Been doing a bit of reading up on alternative energy solutions, and came across this concept recently. Instead if chasing oil or natural gas, there are certain places where natural hydrogen occurs underground. The basic process is that water reacts with iron-rich rocks to form iron oxides and release hydrogen gas. The hydrogen gas would normally seep away, but it can get trapped in some layers of rocks, So if we can drill and extract this hydrogen we get clean energy. This is known as white hydrogen.
Orange hydrogen uses the same chemical process but the reaction is helped along to speed things up a bit. Water saturated with CO2 is pumped down the well and the hydrogen gas extracted. The carbon gets captured within the new minerals formed by the reaction. This is known as orange hydrogen because it turns the rocks orange. So it captures carbon and produces clean energy at the same time.
I find this an interesting concept. Australia seems to have plenty of rocks that are just the right type for this process. Seems like it might be done cheaper than Green Hydrogen which is using solar and wind to split water via electrolysis. I’d like to see some more action on this, if we can do this instead of coal or natural gas that would be nice. Maybe not as a transport fuel but to power the grid and heavy industry.
By the way, the other colours of Hydrogen are:
Grey Hydrogen: Made from natural gas without capturing carbon;
Blue Hydrogen: Made from natural gas with carbon capture technology.