Here we sit in a branchy row, Thinking of beautiful things we know; Dreaming of deeds that we mean to do, All complete, in a minute or two-- Something noble and wise and good, Done by merely wishing we could. We've forgotten, but--never mind, Brother, thy tail hangs down behind!
Rudyard Kipling -- the Jungle Book
By now, you probably heard the story of "Natural Hydrogen," (or "Gold Hydrogen"), the new source of clean energy that should come for free to us, outgassed from the depths of Earth. In 2020, the idea had been reviewed by Zgonnnik (see also an earlier paper), but the concept is becoming popular after it was described in a lengthy article on "Science" of Feb 17, 2022, and then taken up in an enthusiastic article in the NY times on Feb 27, where Peter Coy defines natural hydrogen as a "Gold Mine of Clean Energy Hiding Under our Feet."
Citing from the "Times" article, "....from an economic point of view, it doesn’t make any sense” to use electricity to produce hydrogen, transport the gas and then extract the energy through combustion or a fuel cell. But if hydrogen is available in gaseous form in the ground, the economics suddenly work." So, the energy problem is solved. Move on, folks, now we can restart economic growth.
What's wrong with this idea? Nothing. And everything. There is nothing wrong with finding hydrogen seeping out from the ground. Earth is a huge ball of rock, and it may well be that, somewhere, it contains free hydrogen, maybe even large amounts in comparison with human needs. Unfortunately, everything is wrong with the idea of exploiting that hydrogen as an economic resource. Here, we always stumble on the same problem: most people don't understand the difference between amount, and concentration. A resource is not a resource if it is not concentrated enough. Actually, it has to be concentrated a lot if extracting it has to make sense in economic terms.
Think of the two resources that made our modern world: oil and gas. By a miracle of geology, you can find them concentrated and nearly pure in the structures we call "wells." Drill a hole into one of these wells, and often oil will flow out by itself in huge gushes. Sometimes you have to pump it out, but it still remains a miracle that you can have so much of it, and so concentrated. That's how we could create an entire civilization based on it.
It is not always so easy: concentrated mineral resources are very rare in Earth's crust. The problem is best explained by the example of gold. There are large amounts of it dissolved in seawater: tens of millions of tons. It is a lot of gold, but that's because there is a lot of seawater. If you look at the concentration, we are talking of something around 0.005 parts per billion (ppb) or, if you prefer, a few parts per trillion. That's way too low to make extraction feasible, as it was discovered by the German chemist Fritz Haber in the 1920s when he tried to extract gold from the sea to replenish the coffers of the German state, depleted by the Great War. Actually, he had been experimenting with the idea even before the war, but he failed anyway; it was simply impossible. If it is not concentrated enough, it is not a resource.
So, could there exist underground deposits of natural hydrogen concentrated enough to be usable in practice? We can't say; we only have several reports of hydrogen seeping out of the ground in places scattered all over the planet. There is only one case where one of that seeps is actually used as an energy source. It is in Mali, at Bourakebougou, where natural hydrogen is said to be powering an electricity generator. What is clear, anyway, is that hydrogen will NOT accumulate in the same structures that nicely keep oil and gas safe and concentrated for us -- at least not for a long time. It is such a small molecule that it tends to seep through more or less anything.
We can all be happy for the inhabitants of Bourakebougou who can have electric power for free. Maybe there are other places where the flow of natural hydrogen can be profitably exploited. But don't forget that we have been drilling holes in the ground for almost two centuries. We found a lot of oil and gas, but no hydrogen wells. Granted, the analytical equipment needed to detect hydrogen was not available in the early times of the oil age. And it is also true that geologists soon honed their drills on the geological features they knew could contain hydrocarbons. But if there were amounts of exploitable hydrogen comparable to those of oil and gas, it is hard to think that they would have been missed for so long.
I could also list for you a host of further good reasons that make hydrogen extraction problematic, if not impossible. Not the least important one is that we are starting from scratch for a resource of which we know little or nothing, noting that for known mineral resources, it takes an average of 17 years from discovery to the start of production. And consider that hydrogen cannot use the same infrastructure of pipelines used for natural gas. To transport pure hydrogen, the whole system needs to be rebuilt from scratch. But let me not go into the details. The question is: what are we thinking of doing, exactly? What justifies this sudden burst of enthusiasm?
Peter Coy, in the NY Times, doesn't find a better argument to promote natural hydrogen than citing how the British navy introduced citrus fruit in the diet of sailors to prevent scurvy in 1753. Yes, citrus was a small medical miracle, but miracles are rare and don't come on demand. Rather, "natural hydrogen" looks like a small propaganda operation: a pie in the sky conceived to let us believe that we don't have to worry about anything, no need for changes or sacrifices. We can keep using our beloved fossil fuels because, even if they run out, there is a substitute "hiding just below our feet."
In the end, this story is another illustration of the fantasy of a primate species that arose a few million years ago, abandoning their ancestral forests to move into savannas. Those savanna monkeys have been very successful in many things, including burning huge amounts of fossil hydrocarbons. A dangerous habit that's likely to lead to their extinction because of the damage it is causing to the whole ecosystem. What's remarkable, though, is how easily those monkeys can get excited about novelties, and think that their dreams will be "All complete, in a minute or two" and "Done by merely wishing we could." A description by Rudyard Kipling about the fictional "Bandar Log," the monkeys of the "Jungle Book," but that he surely meant to be also applied to those savanna monkeys known, perhaps improperly, as "homo sapiens."
An Australopithecus Africanus, one of the first savanna monkeys. Surely smart and creative, they were the start of a tradition of dreaming the impossible that continues to this day.