Clean hydrogen could be key to a greener future and there is a lot if it right beneath our feet in the Earth's crust. The trick is knowing exactly where it is and in which conditions it survives. For this, the geology needs to be just right.
Now a team of scientists, including from our Earth Sciences department, have worked out a list of crucial ingredients needed to find these hydrogen hotspots.
This recipe could be essential for finding and extracting this clean gas from underground pockets.
Key ingredients
In the research, the team worked out how and where hydrogen gas forms, how it moves through layers of the Earth to get trapped in a bubble, and what causes it to either stay or disappear.
They liken it to baking a soufflé where you need to get all the ingredients spot on to achieve the perfect dish – amounts, timing and temperature.
Clean hydrogen behaves in a similar way to other gases. Once it has been generated in the Earth's crust, it rises towards the surface.
Along the way it may become trapped by an impermeable layer of rock and accumulate underground, forming a gas field. It is accessed by drilling and produced from wells.
The ingredients for this "hydrogen recipe" – referred to as 'gold' or 'white' hydrogen - can be found in many different types of geological settings around the world.
Some are relatively young, just a few million years old, while others are hundreds of millions of years old.
Greener future
Hydrogen has the potential to power vehicles and industry, generate electricity and heat our homes.
There are many ways to obtain hydrogen but currently a lot of the methods are not particularly clean in environmental terms.
As this clean hydrogen is generated by the natural geochemical processes in the Earth's crust, it could help us transition away from fossil fuels and towards a greener future.
