Apparently, there are deposits of hydrogen that have been naturally produced within the Earth. Will this save us from climate change?
No. Hydrogen is a terrible, terrible fuel for transportation applications or to be transported for use for facility power generation because of its low density even when cryogenically densified into the liquid state (at 33 K under pressure or 20.3 K at ambient pressure), its flammability, high range of detonability, and embrittlement in many common alloys. If we were able to utilize hydrogen as a combustion fuel at a scale comparable to current use of petrofuels (especially at high altitude) it would have a substantial continuous impact on global heating because water vapor is a potent if not persistent greenhouse gas. And hydrogen reservoirs are neither large or concentrated, which would require a large amount of drilling for small return. Even if you buy the entirely unfounded speculation that there are vast accumulations of underground gas sufficient to satisfy “all our hydrogen needs for hundreds of years”, extracting, purifying, and transporting it would almost certainly come at a cost greater than just using renewable energy sources to electrolyze hydrogen for local use from available water sources.
It’s a dumb idea promoted by fabulists looking for a fanciful pixie dust solution that doesn’t require severe austerity, changes to the globalized system of commerce, or reduction of human population to sustainable levels.
Stranger
I think we need a lot more data before we can start to form any useful judgement.
Haven’t researched this in any detail, but it seems that there have recently been a few reports of natural hydrogen deposits which have triggered a lot of speculation about how much more there might be.
I do not get the impression that this is much more than speculation, though? Anyone with real information, please chime in.
Also hydrogen, however sourced, is not a very convenient fuel. It is difficult to transport: needs ridiculously low temperatures if it’s to be kept in liquid form. And even then, the energy density is not great compared with, say, hydrocarbons. And it leaks out of almost anything with ease.
While none of this is technically insoluble, the infrastucture for a ‘hydrogen economy’ would require a large amount of new investment.
Oh. I see that Stranger has just made the same points. I agree with everything he said.
Per my discussions with USGS and DOE, we:
- don’t know how much subsurface hydrogen is available
- don’t know where it is
- don’t know how to stimulate its generation (rocks with more reduced iron species react with water to release hydrogen)
Assuming we have a lot that’s accessible, it would likely need to be converted into something more readily transportable and storable, which would require known technology but substantial infrastructure.
But we need to know 1–3 before the OP’s question can be answered. People are working on that. I am not.
Would you be able to tell us more about this?
I’ve wondered that perhaps hydrogen might be useful as an aviation fuel for larger jets. It would be used in a smaller number of locations - major airports - and consumed in bulk by large jets. The problem I see is storage and how to carry it on aircraft - I assume it would end up being in a giant thermos bottle in the fuselage, the wings being the wrong shape for a good cryogenic load. (Plus, if the fuel is cryogenic hydrogen, you can’t have jets sitting for hours waiting fo their turn to take off).
There’s also the option of generating it from solar energy etc. as hydrogen is a good medium for storing energy.
But as a general motor use, or presumably for home heating and similar applications, I suspect it would be more dangerous than natural gas, which causes a few disasters every so often.
It has a low energy density, especially when you draw the box around the entire fuel system. Jet fuel is kind of magic like that.
You can make SAF from hydrogen and carbon dioxide. It’s just expensive.
Sustainable or Synthetic Aviation Fuel (SAF) could be made from hydrogen and carbon dioxide but unless the latter is sourced from Direct Air Capture (DAC) processes it is still a net greenhouse gas emitter. The primary benefits of SAF are reduced emissions of aromatic pollutants and independence from petrofuel stocks, which is why the US Department of Defense is investing heavily in research to develop production processes.
Stranger
From everything I’ve read, this is an extremely expensive way to produce hydrogen and, combined with the expenses needed to transport it (see @Stranger_On_A_Train’s post above), not a good fuel at all. If we find large deposits sitting around in the ground, that may change the equation. I’m thinking that we put hydrogen-based generating stations (whether fuel cell or otherwise) right next to the hydrogen wells so there would be no transportation problems. We could replace all the natural gas and coal generating stations.
There is a sizable natural hydrogen deposit located between the west coast of the US and the east coast of China. (Among others.)
There seem to be a number of proposals for hydrogen pilot projects in the UK for municipal gas supplies, but when you dig into them, it seems that the actual idea is to introduce something like 20% hydrogen into the mix, rather than a complete replacement. EG:
‘Big bang for Green Energy as English town pioneers a hydrogen gas revolution’
It’s not clear that the existing pipe infrastructure could work with pure hydrogen: the stuff leaks ridiculously easily.
Of course, we have had to do a major rebuild and replace exercise once before when we changed from coal gas to natural gas…?
Ha Ha. Yes, Genepax advertised a car that ran on it.
I wonder what happened to them…?
Poop.
The solution to renewable energy is poop.
For real.
I can help with that. (Pause to flush… oh, oops, I’m wasting a valuable resource).
Do have to wonder what the overall energy budget of the process is, though?
What percentage of the energy content of the final product comes from the, er, biological component?
As Stranger said, perhaps “It’s a dumb idea promoted by fabulists looking for a fanciful pixie dust solution…”
Well, maybe not pixie dust exactly…
But it’s already been burnt.
Um, yeah - I’d have to stop at a lot of Taco Bells on a road trip to produce a volume of human waste matching the capacity of my gas tank; and need even more volume if it’s going to reduced into burnable fuel. Fortunately, I also have a Tesla so maybe I can start a project generating electricity from human-produced natural gas; I produce a lot of that… so my wife tells me.
There are a lot of things that exist. But at what scale? If natural hydrogen were as easy to harvest as fossil fuels, we’d already be doing it.
First we’d have to know that it’s there. Unlike petroleum, hydrogen is odorless and colorless, and as one of the links I posted says, no one was testing for its presence until recently.
No. Water vapor is almost exclusively a feedback directly correlated with temperature change and not a climate forcing, except for very minor amounts in the stratosphere mostly resulting from oxidation of CH4. The difference between a forcing and a feedback is very fundamental. This is why water vapor is never included in the categorization of radiative climate forcings. The idea that increased water vapor emissions at the surface would have a “substantial” effect on global warming is ridiculous. What it would mainly do is produce more rain as the atmosphere sheds the excess.
I was watching a news report this morning on Toyota’s hydrogen fuel program, which has been their main line of development ahead of EVs. It featured a firm in Melbourne which had their small hydrogen fleet, fuelled from a Toyota hydrogen plant nearby. That sounded good, but Toyota was heavily subsiding their vehicles. The quoted figures, if I remember correctly, was 6 hydrogen vehicles sold in Australia in the past year [that firm’s fleet?] and something like 400-500 in Japan.
As the cost of producing convenient spot-supply electricity continues to drop, it makes it harder to see how hydrogen can get rolled out in a similarly convenient way that it remains viable. Obviously cars are not the world, but even if hydrogen becomes the main industrial and energy fuel, that’s still a big market that it cannot feed.