A well drilled for water instead produced 98% pure hydrogen in 2012. The hydrogen was discovered at a relatively shallow depth in a small village in the south of Mali, Africa, by a local company, Petroma. It is the first and only hydrogen producing well in the world. It was estimated the well will produce hydrogen for another 15 years. The hydrogen is being used to power an electric generator and now is used only to power lighting and make ice. However, the village expects to eventually use the electricity to power water pumps, operate grinding mills and provide lighting for schools.
Picture of the wellhead producing natural hydrogen, which powers electric generating facility in Mali. Screenshot from the youtube video.