Those Pesky Savanna Monkeys and Their Dreams of Golden Hydrogen

 

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.

The Great Turning Point for Humankind: What if Nuclear Energy had not been Abandoned in the 1970s?

  The Italian translation of Walt Disney's book, "Our Friend, the Atom," originally published in 1956. It was a powerful pitch of the nuclear industry to sell a completely new energy system to the world. It could have been a turning point for humankind, but it didn't work: nuclear energy was abandoned in the 1960s-1970s. It was probably unavoidable: too many factors were staked against the nuclear industry. But we may wonder about what could have happened if it had been decided to pursue nuclear energy and abandon fossil energy. (In the background: a completely different concept, that of "holobionts,")

I remember having read Walt Disney's book, "Our Friend, the Atom," (1957) in the 1960s when I was, maybe, 10 years old. That book left a powerful impression on me. Still today, when I visualize protons and electrons in my mind, I see them in the colors they were represented in the book: protons are red, electrons are blue or green. And I think that one of the reasons why I decided to study chemistry at the university was because of the fascinating images of the atomic structure I had seen in the book.

More than 60 years after its publication, "Our Friend the Atom" remains a milestone in the history of nuclear energy. You can easily find on the Web the Disneyland TV episode from which the book was derived. It is still stunning today in terms of imagery and sheer mastery of the art of presentation. The nuclear industry was in rapid expansion and it saw itself as able to grow more. Hence, a pitch for the "Atomic Age" that would have brought cheap and abundant energy for everyone, perhaps even energy that was "too cheap to meter." 

It didn't work. You see in the figure the number of new reactors installed worldwide. It peaked around 1970, and plans to build new reactors must have been declining earlier than that. Already in the 1960s, the enthusiasm for nuclear energy was falling, a trend that would last until now, despite some recent signs of a possible restart. (image from Univ. Texas)

What went wrong? Today, the whole story is usually dismissed as the result of the machinations of those evil Greens who had opposed nuclear energy for ideological reasons. Yet, the popular "smiling sun" campaign didn't become widespread before the late 1970s, when the nuclear industry was already in free fall. Never in their history, the Greens had been able to stop an industrial field that was making money. Why should they have been so successful with the nuclear industry? (by the way, with a campaign that started at least a decade after that the intended target had begun its decline. Those damn Greens even had time machines!)

Reviewing this old story, we see that the smiling sun campaign was not the cause, but a symptom of the troubles that the nuclear industry was facing. Up until the 1950s, the industry had prospered almost exclusively in the military market, producing mainly nuclear warheads. The production of electric power for the civilian market was a side job, just like the production of isotopes for research and for medical applications. The problem was that warheads were being stockpiled in absurd numbers, well beyond the reasonable needs (if we want to use that term) of national defense. 

It must have been clear already in the 1950s that the industry was saturating its market. The only solution to stimulate the demand was to start an actual nuclear war. Surely, it must have been considered but, fortunately, not everyone agreed on that idea. 

But where to find new markets for the nuclear industry? With already so many nuclear weapons around, a possible solution was to move into the civilian market and to expand outside the US national boundaries. In the 1950s, the US engaged in a program that started with the speech by President Eisenhower known as "Atoms for Peace" in 1953. The idea was to disseminate nuclear technology all over the world as a way to produce energy and other useful products. Walt Disney's 1956 movie was an offshoot of this program.

Seen in retrospective, the "Atoms for Peace" program couldn't possibly have worked, and it didn't. The nuclear industry faced a series of hurdles, each one sufficient to stop its growth, alone. All together, they were truly too much. Here is a list.

1. A mineral resource problem. In the 1950s, it was already known (*) that the mineral reserves of fissile uranium, the 235 isotope, were insufficient for nuclear plants to take over the task of energy production worldwide. That could have been possible only by means of the new and scarcely tested technology of "breeding." A few attempts were made to build commercial breeding reactors, but they were victims of the general rule that everything always costs more and takes more time. Gradually, the funds needed to keep developing the technology dried out and the efforts stopped. The best known of these reactors, the French "Superphenix" was closed in 1996, but it was clear much earlier that it had not been a success. No breeders, no atomic age.

2. A pollution problem. In the 1950s, nuclear waste was not seen as a major problem, but it was also clear that a substantial increase in the number of nuclear reactors would have created the necessity of doing something with the radioactive waste. And it started to be understood that dismantling the old nuclear reactors after the end of their life was a long and expensive task. Some of the waste would require centuries or millennia to become inoffensive. And, in all cases, the costs involved were huge and who was going to pay? The question was never answered at that time, and it remains unanswered today.

3. A commercial problem. Electrical energy from nuclear reactors always remained more expensive than the energy produced by gas or coal. So, the production of energy for the civilian market needed to be subsidized to be competitive. Up to 1977, subsidies were provided indirectly by the military industry with the purchase of the plutonium produced by the reactors, used to make nuclear warheads. These subsidies were abolished by president Carter in part because the US had already too many warheads, and in part to avoid the proliferation of fissile material. At this point, the industry was not any more competitive and who would invest money in a non-competitive industry? 

4. A competition problem. In the 1960s, the concept of "hydrogen economy" started becoming popular. For the nuclear industry, it seemed to be a good idea to claim that they could produce not only electric power, but also a fuel that could power vehicles. Unsurprisingly, that put the nuclear industry in direct competition with the fossil fuel industry. We know that everyone tends to defend their turf when it is threatened and we can't imagine that the fossil industry would supinely accept to be superseded. By the late 1970s, an aggressive public relations campaign based on the "smiling sun" symbol had turned nuclear power into everyone's bugaboo. Probably we will never know who financed that campaign, but we know who benefited from it.

5. A strategic problem. The idea of "atoms for peace" was complete nonsense in strategic terms. It just put the US in an impossible strategic quandary: how to stop nuclear proliferation while at the same time disseminating nuclear technologies all over the world? The solution was to quietly forget about atoms for peace while aggressively stopping the construction of nuclear reactors everywhere, especially in countries believed to be strategically unreliable. In 1981, the "Tammuz" reactor under construction in Iraq, near Baghdad, was destroyed by the Israeli air force. In 1987, a referendum against nuclear energy was held in Italy, a country believed to be at risk as an ally of the US because of the presence of a large Communist Party. The referendum forced the Italian government to dismantle four already built reactors and never to engage again in nuclear energy production. Iran continued the nuclear program that had been started with the "atoms for peace" program, but it was sabotaged at every step. From the 1980s onward, it became clear that not only nuclear weapons but also nuclear energy was something that belonged only to a selected club. 

 

You see that, as usual, when something must happen, you cannot stop it from happening. That the nuclear industry was to fail was written on the wall of the reactors because of a series of factual circumstances, surely not because a bunch of long-haired Greens were protesting in the streets. Yet, it is not impossible to think that history could have followed a different path. 

Imagine that the US military leaders had stomped their feet on the ground and said, "we are going to have breeders in America." Imagine that sufficient funds could have been funneled into the task. Finally, imagine that the technological problems of breeders could have been solved. At that point, the US and the whole Western World could have switched to a largely nuclearized energy system, possibly including a hydrogen-powered transportation system. It is unlikely that China and the Soviet Union would not have followed along the same path. And it would have been difficult to stop nuclear technology from diffusing in other regions of the world. It would have been the "Atomic Age" that was dreamed of in the 1950s.

What kind of world would that be, today? Theoretically, we would much more energy than we have today, at least for the elite countries that had embarked on the nuclearization of their economies. And this energy could be produced without emitting greenhouse gases into the atmosphere, so that Earth's climate would not have been affected, at least not directly.

But we would have faced a completely different range of problems. With the Atomic Age, the amount of fissile material available in the world would have been multiplied by one or two orders of magnitude and it is almost unthinkable that it would stay forever out of the hands of the many petty tyrants, fanatical religious leaders, and assorted psychopaths who tend to crave for that kind of things. 

Consider also that nuclear plants (especially breeders) offer a delicious target for military and terrorist attacks not just for their strategic value but also for the possibility of spreading radioactive material around and making large areas of the targeted territory uninhabitable. So, you may imagine what kind of problems we could have today. Even for a limited nuclear exchange, the "nuclear winter" scenario, proposed in the 1990s, implied a cooling period sufficiently long to exterminate most of humankind. The idea was heavily criticized, but never really debunked. And that without mentioning the possibility of the mismanagement of the nuclear wastes and the fact that plutonium is among the most poisonous substances known to humans.

Consider also another problem, much bigger, that lurks unrecognized in the shadows for the atomic age scenario. In the 1950s, Marion King Hubbert was working on oil depletion and in 1956 he proposed his famous "bell shaped" production curve, later known as "peak oil." Hubbert also proposed that nuclear energy would replace fossil fuels. But note in the figure below how, in his view, nuclear energy would not have prevented "peak oil" from taking place at about the same time that was foreseen without nuclear energy.  Hubbert understood very well that the enormous effort needed to build the new nuclear infrastructure would have had to be based on fossil fuels, and so would not have reduced their production.

Now, note something in the image: whereas fossil fuels follow a bell-shaped production curve, nuclear energy reaches a plateau and remains there for thousands of years. Why?

Hubbert must have been well aware that the "thousands of years of supply" that the nuclear industry often claimed for the mineral reserves of uranium were possible only if production were not to increase over a certain rate. But what would have stopped people from increasing energy production even more? You think that people would have been thinking, "now we have enough" and then spend their time relaxing? One world: pyramids. 

Why wouldn't Plutonium follow the same trajectory of oil, a "bell-shaped" curve, peaking and starting to decline afterward? (Want to mention thorium? Sure, but it is another finite resource, it doesn't change the concept). So, it would grow, peak, and then decline.

It is impossible to calculate when "peak plutonium" could take place in a fully nuclearized world. It would depend on many factors, the available resources, the efficiency of the breeding technology, the energy return on investment, the cost of waste management, and more. In a previous post, I made some very rough estimates: if the plutonium-based economy were to be run on the known laws of the economy, it is hard to imagine that the reserves of fissionable materials would last for more than a few centuries, possibly even less than a century. (Fusion? Sure, let's wait 50 more years and....).

And here we stand. Playing the "what if" game is a lot of fun, but we should remember that we are talking about the dream expressed by Walt Disney's "Our friend, the Atom," A dream that, likely, had the same chances to turn into reality as others proposed by Walt Disney, such as for a poor country girl to marry a prince. And it is not at all guaranteed that the country girl would have a happy marriage!

We don't know if a plutonium-based economy ever was something more than a dream. Today, it is too late to turn back to a moment in history that is past and gone, although it is not impossible that someone will want to try to resurrect a dream that could easily turn into a nightmare. 

What we know is that, as always, we stand at the intersection of past and future, in that fleeting moment we call "present." From now on, infinite possibilities branch out. Those leading to a peaceful and prosperous future are few, maybe there are none. But we must plod on. It is a journey that will lead us somewhere, even though we can't say where.

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(*) The story of the assessment of the uranium reserves is fascinating in itself. Palmer Putnam published in 1953 the book "Energy in the Future" where he carried out one of the first quantitative assessments of the potential of fission energy in terms of mineral reserves of uranium  See below the relevant paragraph

 

 

 

 

Note the key words: "assuming breeding." That is, the assumption is that energy can be extracted from both isotopes of uranium, the 235 and the 238. The result is 1700 Quads, or about 100 times the energy content of the (then) known oil and gas reserves. 

 

You understand why in the 1950s it became obvious that breeding plutonium was absolutely necessary for a nuclear-based economy. If only U235 were to be "burned," then the resource would be suddenly reduced to 0.72% of the total, that is to 12 Quads. Assuming an optimistic 30% efficiency (but, really, way too optimistic), the total obtainable would be 4 Quads. Earlier on, Putnam had established that the world would require more than 70 Q of energy by the year 2000. No breeding, no atomic age. Simple.

A Concise History of the concept of "Hydrogen Economy"

Reposted from "The Hydrogen Skeptics" blog. 

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The concept of "hydrogen economy" has a distinct "1960s" feeling. It is the idea of maintaining the lifestyle of the post-war period, with suburban homes, green lawns around them, two cars in every garage, all that. The only difference would be that this world would be powered with clean hydrogen. It all started with the dream of cheap and abundant energy that nuclear plants were believed to be able to produce. The idea changed shape many times, but it always remained a dream, and probably will continue to remain a dream in the future.

 

by Ugo Bardi

Before discussing the history of the concept of "hydrogen economy" we should try to define it. As you should expect, there are several variations on the theme but, basically, it is not about a single technology but a combination of three. Hydrogen would be used for: 1) energy storage, 2) energy vectoring, and 3) fuel for vehicles. 

This "hydrogen triad" misses the fundamental point of how hydrogen should be created. Often, that's supposed to be done using electrolysis powered by renewable energy but, alternatively, from natural gas, a process that would be made "green" by carbon sequestration. There are other possibilities, but all have in common being multi-step processes with considerable efficiency losses. And the fact of never having been proven to be economically feasible on a large scale.

Indeed, the immediate problem with replacing fossil fuels is not vectoring or storage, surely not powering individual cars. It is the enormous investments needed to build up the primary production infrastructure that would be needed in terms of solar or wind plants (or nuclear), which don't seem to be materializing fast enough to generate a smooth transition. Surely, not growing fast enough to be compatible with a relatively inefficient infrastructure based on hydrogen. Nevertheless, the "hydrogen economy" seems to be rapidly becoming the center of the debate. 

Indeed, the Google Ngrams site shows two distinct peaks of interest for the concept, both grew rapidly and rapidly faded away. But it seems clear that a third cycle of interest is starting to appear, and that is confirmed by what we can read in the media.

So, why this focus on a technology that lacks the basic elements that would make it useful in the near term? As it is often the case, ideas do not arrive all of a sudden, out of the blue. If we want to understand what made hydrogen so popular nowadays, we need to examine how the idea developed over at least a couple of centuries of scientific developments.

That hydrogen could be used as fuel was known from the early 19th century. Already in 1804, the first internal combustion engine in history was powered by hydrogen. The first explicit mention of hydrogen as an energy storage medium goes back to John Haldane in 1923, where he even discussed the possibility of using "oxidation cells" that we call today "fuel cells," invented by William Grove in 1838.

But these ideas remained at the margins of the discussion for a long time: no one could find a practical use for a fuel, hydrogen, that was more expensive and more difficult to store and use than conventional fossil fuels. Things started to change with the development of nuclear energy in the 1950s, with its promise of a new era of abundance. But, in the beginning, hydrogen found no role in the nuclear dream. For instance, you wouldn't find any mention of hydrogen as an energy carrier in the "manifesto" of the atomic age: the 1957 TV documentary by Walt Disney, "Our Friend, the Atom." 

In the book derived from the movie, there was an entire chapter dedicated to how nuclear energy was going to power homes, ships, submarines, and even planes. But nothing was said about the need for fuels for road transportation. The atomic car was just briefly mentioned as "not a possibility for the near future." The engineers of Ford thought otherwise when, in the same year (1957), they proposed the concept of a nuclear-powered car, the Ford Nucleon. But nobody really believed that such a car could ever be produced. At the beginning of the nuclear age, there was no concern about climate change, and no one foresaw the need or the possibility of entirely replacing fossil fuels from the world's energy infrastructure.

The idea of hydrogen as an element of the new nuclear infrastructure started gaining weight only in the 1960s, in parallel with the problems that the nuclear industry was experiencing. The assessments of the world's uranium ores showed that mineral uranium was not abundant enough to support a large expansion of nuclear energy as envisaged at that time. But the industry had a technological solution: "fast" reactors that could be used to "breed" fissile materials in the form of plutonium. The fast reactor technology could have increased the duration of the uranium reserves of several hundred years, perhaps thousands. 

Fast reactors turned out to be more expensive and complex than expected, but the problem was not technological, it was strategic. The "plutonium-based economy" would have generated a gigantic proliferation problem. It was clear to the Western leaders that diffusing this technology all over the world put them at risk of losing the monopoly of weapons of mass destruction that they shared with the Soviet Union. 

So, if fast breeders were to be built, they needed to be only a few and to be very large to allow tight military control. They also needed to be large to exploit economies of scale. But that led to another problem: how to carry the energy to consumers? Electrical lines have a distance limit of the order of a thousand km, and can hardly cross the sea. The kind of plants envisaged at that time would be spaced much more than that from each other. It was at this point that the idea of hydrogen as an energy carrier crept in. It could have been used to distribute nuclear energy at a long distance without the need to distribute the reactors themselves. 

It was a concept discussed perhaps for the first time in 1969 by the Italian physicist Cesare Marchetti, He was, (now he is in his 90s) a creative scientist who proposed that just 10 gigantic fast reactors of a few TW each would have been enough to power the whole world. The reactors could be built on remote oceanic islands, where the water needed for cooling would have been abundantly available. Then, the energy would have been transformed into liquid hydrogen at low temperature and carried everywhere in the world by hydrogen carrier ships. In the image from one of Marchetti's papers, you see how an existing coral atoll in the South Pacific Ocean, Canton Island, could be converted into a Terawatt power nuclear central.

To paraphrase the theme of Disney's "nuclear manifesto" of 1957, the hydrogen genius was now out of the bottle. In 1970, John Bockris, another creative scientist, coined the term "hydrogen-based economy." In the meantime, NASA had started using hydrogen-powered fuel cells for the Gemini manned spacecraft program. It was only at this point that the "hydrogen car" appeared, replacing in the public's imagination the obviously unfeasible nuclear-powered car. 

 

It was a daring scheme (to say the least), but not impossible from a purely technological viewpoint. But, as we all know, the dreams of a plutonium economy failed utterly. With the oil crisis of 1973, the nuclear industry seemed to have a golden opportunity. Instead, it collapsed. We can see in the Ngrams how the concept of "fast breeder" picked up interest and then faded, together with that of nuclear energy. The reasons for the downfall of the nuclear industry are complex and controversial but, surely, can't be reduced to accusing the "Greens" of ideological prejudices. Mainly, the decline can be attributed to two factors: one was the fear of nuclear proliferation by the US government, the other the opposition of the fossil fuel industry, unwilling to cede the control of the world's energy production to a competitor. Whatever the causes, in the 1980s the interest in a large expansion of the nuclear infrastructure rapidly declined, although the existing plants remained in operation.

And hydrogen? The downfall of nuclear energy could have carried with it also the plans for hydrogen as an energy carrier, but that didn't happen. The proponents repositioned the concept of "hydrogen economy" as a way to utilize renewable energy. 

One problem was that renewable energy, be it solar, wind, or whatever, is inherently a distributed technology, so why would it need hydrogen as a carrier? Yet, renewables had a problem that nuclear energy didn't have, that of intermittency. That required some kind of storage and hydrogen would have done the job, at least in theory. Add that at in the 1980s there were no good batteries that could have powered road vehicles, and that made the idea of a "hydrogen car" powered by fuel cells attractive. Then, you may understand that the idea of a hydrogen-based economy would maintain its grip on people's imagination. You can see in the figure (from Google Ngrams) how the concept of "hydrogen car picked up interest. 

It was a short-lived cycle of interest. It was soon realized that the technical problems involved were nightmarish and probably unsolvable. Fuel cells worked nicely in space, but, on Earth, the kind used in the Gemini spacecraft were rapidly poisoned by the carbon dioxide of the atmosphere. Other kinds of cells that could work on Earth were unreliable and, more than that, required platinum as a catalyst and that made them expensive. And not just that, there was not enough mineral platinum on Earth to make it possible to use these cells as a replacement for the combustion engines used in transportation. In the meantime, oil prices had gone down, the crises of the 1970s and 1980s seemed to be over, so, who needed hydrogen? Why spend money on it? The first cycle of interest in the hydrogen-based economy faded out in the mid-1980s. 

But the story was not over. Some researchers remained stubbornly committed to hydrogen and, in 1989, Geoffrey Ballard developed a new kind of fuel cell that used a conducting polymer as the electrolyte. It was a significant improvement, although not the breakthrough that it was said to be at the time. Then, in 1998, Colin Campbell and Jean Laherrere argued that the world's oil resources were being rapidly depleted and that production would soon start declining. It was a concept that, later on, Campbell dubbed "Peak Oil." In 2001, the attacks on the World Trade Center of New York showed that we lived in a fragile world where the supply of vital crude oil that kept civilization moving was far from guaranteed. Two years later, there would come the invasion of Iraq by the US, not the first and not the last of the "wars for oil." 

All these factors led to a return of interest in hydrogen energy, stimulated by the popular book by Jeremy Rifkin, "The Hydrogen Economy," published in 2002. The new cycle of interest peaked in 2006 (again, look at the Ngrams results, above), and then it faded. The problems that had brought the first cycle to its end were still there: cost, inefficiency, and unreliability (and not enough platinum for the fuel cells). Besides, a new generation of batteries was sounding the death knell for the idea of using hydrogen to power vehicles. Look at the compared cycles of hydrogen and of lithium batteries.

 Note the different widths of the peaks. It is typical: technologies that work (lithium) keep being mentioned in the scientific literature. Instead, technologies that are fads (hydrogen) show narrow peaks of interest, then they disappear. You can't just keep telling people that you'll bring them a technological marvel without ever delivering it. 

At this point, you would be tempted to say that hydrogen as an energy carrier and storage medium is a dead platypus. But no, the discussion on the hydrogen economy is restarting, research grants are being provided, plans are being made. 

Did something change that's generating this new cycle? Not really, the technologies are still the same. Surely there have been marginal improvements, but hydrogen remains an expensive and inefficient method to store energy. So, why this new round of interest in hydrogen?

The vagaries of memes are always open to interpretation, and, in this case, we can suppose that one of the elements that push hydrogen back to the global consciousness lies in its origins of supporting technology for a centralized economy, the one that would have resulted from the widespread use of fast breeder reactors. In this sense, hydrogen is in a different league from that of most renewable technologies that exist and operate over a distributed network. 

So, even if the nuclear industry is today a pale shadow of what it was in the 1960s, there remains the fossil fuel industry to champion the role of centralized energy supply. And, obviously, the fossil fuel producers, who produce hydrogen from fossil sources, are those who are going to benefit most by a return to hydrogen, no matter how short-lived it will be. 

There may be another, deeper, reason for the success of the hydrogen meme with the public. It is because most people, understandably, resist change even when they realize that change is necessary. So, replacing fossil fuels with electricity-producing renewables is something that will force most of us to radical changes in our lifestyle. Conversely, hydrogen promises change with no change: it would be just a question of switching from a dirty fuel to a clean one, and things would remain more or less the same. We would still fill up the tanks of our cars at a service station, we would still have electric power on demand, we would still take two weeks of vacation in Hawai'i once per year. 

Unfortunately, people change only when they are forced to and that's what's probably going to happen. But, for a while, we can still dream of a hydrogen-based society that seems to be curiously similar to that of the US suburbs of the 1960s. Dreams rarely come true, though.