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Comment by aunty_helen

16 hours ago

Kinda glad this is the case. When people go out of their way to avoid common sense they should be punished.

Hydrogen is such a terrible idea it was never getting off the ground. There seems to be some kind of psychosis around it being the next oil and therefore greedy people want to get in early on. But this blinds them to the basic chemistry and physics.

People looked at how the cost of wind and solar went down and made a assumption that green hydrogen would follow. The reasoning was that the cost of green hydrogen was energy, and thus at some point green hydrogen would be too cheap to meter.

The whole energy plan of central/northen Europe, especially Germany, was built for the last several decades on the idea that they would combine wind, solar and cheap natural gas and then replace the natural gas part with green hydrogen. In Sweden there were even several municipalities that spear headed this by switching mass transportation and heating towards hydrogen, initially with hydrogen produced through natural gas, as a way to get ahead on this plan.

The more sensible project were the green steel project. As experts in green hydrogen said consistently said through those decades, is that green steel would be the real test to make green hydrogen economical. The economics of burning it for energy or transportation would come several decades later, if ever. The green steel project however has not ended up as planned and gotten severely delayed and has seen a cost increase by an estimated 10x. municipalities are now giving up the hydrogen infrastructure and giving it an early retirement, as maintenance costs was significantly underestimated. There is very little talk now about replacing natural gas with green hydrogen, and the new plan is instead to replace the natural gas with bio fuels, hinted at carbon capture, at some unspecified time.

  • Agreed on "green steel".

    In general, "green hydrogen" makes the most sense if used as a chemical feedstock that replace natural gas in industrial processes - not to replace fossil fuels or be burned for heat.

    On paper, hydrogen has good energy density, but taking advantage of that in truth is notoriously hard. And for things that demand energy dense fuels, there are many less finicky alternatives.

  • I had to Google what is green hydrogen. It is hydrogen produced by electrolysis.

    If you've already got the electricity for electrolysis, would it not be more efficient and mechanically simpler to store it in a battery and power an electric motor?

    • > If you've already got the electricity for electrolysis, would it not be more efficient and mechanically simpler to store it in a battery and power an electric motor?

      Yes, if you actually have the batteries.

      Between around 2014-2024, the common talking point was "we're not making enough batteries", and the way the discussions went it felt like the internal models of people saying this had the same future projections of batteries as the IEA has infamously produced for what they think future PV will be: https://maartensteinbuch.com/2017/06/12/photovoltaic-growth-...

      I've not noticed people making this claim recently. Presumably the scale of battery production has become sufficient to change the mood music on this meme.

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    • The value proposition of hydrogen is energy density. Batteries have low energy per unit of volume and awful energy density by unit of mass. You will never, ever, fly across the Pacific on a battery powered aircraft. Transoceanic shipping is also not feasible with batteries (current and proposed battery powered shopping lanes are short hops of a couple hundred kilometers or less).

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    • I think that is the way it is headed. But you never know. Sometimes when comparing it helps me to reduce these things down to lower levels.

      What is a battery? A chemical cell to store hydrogen and oxygen(true, it does not "have" to be hydrogen and oxygen but it usually is) to later get energy out of. For example lead-acid(stores the oxygen in the lead-sulfate plates and the hydrogen the the sulfuric acid liquid) or nickle-metal(charges into separate oxygen and hydrogen compounds, discharges into water) the lithium cell replaces hydrogen with lithium. Consider a pure hydrogen, oxygen fuel-cell, it could be run in reverse(charged) to get the hydrogen and oxygen and run forward(discharged) to get electricity out of it. So it is a sort of battery, a gas battery. Gas batteries are generally a bad idea, mainly because they have to be so big. Much time and effort is spent finding liquids that can undergo the oxidation/reduction reactions at a reasonable temperature. But now consider that there is quite a bit of oxygen in the air, if we did not have to store the oxygen our battery could be much more efficient, This is the theory behind free-air batteries. But what if our battery did not have to run at a reasonable temperature. We could then use a heat engine to get the energy out. And thus the Mirai. They are shipping half of the charged fluid to run in a high temperature reaction with the other half(atmospheric oxygen) to drive a heat engine that provides motive power.

      As opposed to having the customer run the full chemical plant to charge and store the charged fluids to run in a fuel cell to turn a electric motor for motive power. Honestly they are both insane in their own way. But shipping high energy fluids tend to have better energy density. Perhaps the greatest problem in this case is that it is in gaseous form(not very dense) so has no real advantage. Unfortunately one of the best ways to retain hydrogen in a liquid form is carbon.

    • Before the introduction of 800V charging architectures, long charge-time for EVs was a big con. Hydrogen Cell vehicles were supposed to be EVs with drastically faster fill-up times. The tradeoff was more complex delivery infrastructure.

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    • Green hydrogen is a way to ship solar power elsewhere that doesn't have it, similar to a battery, but with the advantage of being able to be piped/pumped/liquified etc.

      3 replies →

  • That was extremely stupid of them then. Hydrogen has been very good at one thing: subsidy extraction. But I don't think it was or ever will be a viable fuel for planetary transportation.

  • The idea was to transition from coal to natural gas while using solar and wind to reduce fuel consumption, thereby significantly reducing CO2 emissions. Any claims of hydrogen being burned were either lies to the public to get the gas plants built despite the non-green optics or lies to investors as part of a fraud scheme.

    • Hydrogen burning could have a place in an all-renewable grid: it could be much more economical for very long duration storage than using batteries. The last 5-10% of the grid becomes much cheaper to do with renewables if something like hydrogen (or other e-fuels) is available.

      A competitor that might be even better is very long duration high temperature thermal storage, if capex minimization is the priority.

  • Good context. It's a shame none of these people did high school chemistry.

    I do remember there being some news about the steel manf.

    I wonder if further advancements in rocketry are adding H2 tech that could help us manage the difficulties of dealing with the stuff. It still only makes sense in very specific circumstances. Like when you need energy in tank form.

    But I think battery / biofuel is the future.

> There seems to be some kind of psychosis around it being the next oil

There's a very well financed propaganda campaign.

  • Yes, it's not the new oil, it's the same oil in "green" packaging. Plus some comforting lies about carbon capture.

    • Even if it was fully green, you can’t run an electrolysis system from home. So you have to buy it, so there’s a market and an expensive solution.

      Electricity comes out the wall.

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  • Same with nuclear. The most expensive form of electricity generation there is. No grid operator wants to touch it, but the nuclear industry has been very busy lobbying congress and both the current and last administration.

    • Nuclear is incredibly energy dense, can be stockpiled for a long time and is extremely safe. Yes its expensive but its one those industries any serious nation needs to subsidise for the energy security it offers and the countless high skill jobs it fosters.

There is a great way to store, transport, and use hydrogen:

Bind it to various length carbon chains.

When burned as an energy source the two main byproducts are carbon dioxide which is an essential plant growth nutrient, and water which is also essential to plant growth.

Environmentalists will love it!

And they can prise my turbo diesel engines from my cold dead hands.

  • Carbon Dioxide is a greenhouse gas, which makes the world warmer on average. It also lowers the PH levels of the oceans.

    If the oceans die, its very likely that many or even most humans will also. As a human I am pretty strongly opposed to dying, but thats just, like, my opinion man.

    • The major problem with hydrocarbons today is that we are releasing carbon dioxide stored hundreds of millions of years ago.

      If, theoretically, you could produce hydrocarbons from the carbon dioxide that is currently in our atmosphere, then it could be a substantial reduction in net carbon dioxide being added; and it would be compatible with the fuel infrastructure of today.

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    • It's possible to synthesise hydrocarbon analogues of petroluem-based fuels. The problem to date has been that this isn't cost-competitive with petroleum, though the difference is narrower than you might expect. Most famously, a Google X Project attempted this and succeeded technically, but the economics were unfavourable: Project Foghorn: <https://x.company/projects/foghorn/>. Both Germany and South Africa have performed synfuel production (from coal) at industrial scale since the 1930s / 1950s, respectively. Using non-fossil carbon is largely the same chemistry; the process does in fact scale.

      Fischer-Tropsch and Sabatier process can both operate with scavenged CO2. There's been some work since the 1990s utilising seawater as a CO2 source, with CO2 capture being far more efficient than from atmospheric sources.

      Whilst hydrocarbons have numerous downsides (whether sourced from fossil or renewable sources), they are also quite convenient, exceedingly well-proven, and tremendously useful. In some applications, particularly marine and aviation transport, there are few if any viable alternatives.

      I've commented on this numerous times at HN over the years: <https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...>.

  • We live (or at least used live) in a very nice climate equilibrium with the CO2 level we had. Pushing us into another climate equilibrium looks very dangerous for human civilization. However I concede that it might be advantageous for certain plants, but I am not a plant so I am mostly concerned about human civilization.

    • > However I concede that it might be advantageous for certain plants

      Plants are highly dependent on their climactic settings, upending a climate equilibrium is awful to the average plant. And looking at past climactic change events, "another climate equilibrium" is something that happens on kiloyear scales (ages, in geochronologic units).

Synthetic fuels (including hydrogen) do still make a lot of sense for heavy stuff like trucks, buses or trains, and aircraft where the energy density is a big plus. Those are where you'd expect to see hydrogen take off first, not passenger cars. Same as how diesel started in trucks - expensive engines but economical when amortized and worth it for heavy usage applications.

If they couldn't crack those areas, no chance in the highly competitive passenger car space.

  • > Synthetic fuels (including hydrogen) do still make a lot of sense for heavy stuff like trucks, buses or trains

    Synthetic fuels don't "make a lot of sense" for "heavy stuff", rail electrification has been the norm everywhere the capital costs were justified (it's at about 30% worldwide, 57% in europe, some countries like Switzerland are nearly 100% electric).

    Synthetic fuels make sense for autonomy reasons when you can't tether the "heavy stuff", but fuel engines absolutely suck for heavy work loads, electric transmissions started being a thing before railway electrification even was.

    And of course those are situations where hydrogen sucks, fuel is useful there because it's a stable and dense form of energy storage which is reasonably easy to move about without infrastructure, you can bring a bunch of barrels on a trailer, or tank trailers, to an off-grid site and fuel all your stuff (including electric generators). With hydrogen you're now wasting a significant portion of the energy you brought in trying to keep the hydrogen from going wild.

  • Trucks and busses would be better off with battery swaps at depo like electric forklifts do. More mileage more towing weight for trucks, just stack more batteries. Overweight? Use a diesel.

    Trains is an easy one, over head lines.

    Aircraft, I think short distance trips <1hr maybe otherwise biofuel. Likely we’ll see biofuels widely used by 2040. Electric motors on a 777, I’m not sure.

    • With the upcoming MCS charging standard you won't need battery swaps for trucks or busses. Even today you have trucks that can charge with up to 400 kW, which is good enough for charging during mandatory pauses or downtimes.

Yeah, it might make sense for some industrial processes as natural gas or coal replacement, but not really anywhere else just because all the tricky leaks and invisible fire hazards.

Green hydrogen makes sense as a way to ship solar power to places that don't have it.

Using it as a car fuel only makes sense as an interim step to full renewable/EVs.

Internal combustion engines, no matter what the fuel, are way more complicated than electric motors. Doesn't matter how you slice and dice the argument.

  • Also the losses are much higher when converting electricity to hydrogen and then burning that hydrogen.

> Hydrogen is such a terrible idea it was never getting off the ground.

It's coming from Toyota because Toyota can't wrap its head around not making engines. Ironically, the place hydrogen might work is airplanes where the energy density of batteries doesn't work.

  • > the place hydrogen might work is airplanes where the energy density of batteries doesn't work.

    How is that going to work? Cryogenic liquid hydrogen? High pressure tanks? Those don't seem practical for an airplane.

    What does work for airplanes is to use carbon atoms that hydrogen atoms can attach to. Then, it becomes a liquid that can easily be stored at room temperature in lightweight tanks. Very high energy density, and energy per weight!

    (I think it's called kerosene.)

    • Diesel, kerosene, rocket propelled RP1, and fuel oil / bunker fuel in the case of cargo ships.

      It’s not a coincidence that where easy of handling, storage safety, and high energy density are needed everything seems to converge on compression ignition medium to long chain liquid hydrocarbons.

  • WTF , you are commenting about FCEV - these things dont have engines!

    The strategy clearly stated by Akio Toyoda is multiple power train technology. You can listen to his interviews on the subject, some are in Japanese, but as you have stated a clear and unambiguous interpretation of Toyota's policy I will assume you have that fluency.

    (Automotive OEMs are assemblers, the parts come from the supply chain starting with Tier 1 suppliers. In that sense TMC does not do "making engines", but possibly the nuance and consequences here of whether not it "wraps it's head" to "makes things", vs if it has the capability to specify, manufacture distribute something at scale with a globally localized supply chain AND adjust to consumer demand/resource availability changes 5 years after the design start - in this context i ask you, can you "wrap your head" around the latest models that are coming out in every power train technology fcev, (p)hev to bev)

  • Has the hydrogen storage problem been solved yet?

    Last time I checked it needs to be stored in cryo / pressure vessel and it also leaks through steel and ruins its structural properties in the process.

    • > Has the hydrogen storage problem been solved yet?

      No. Not for using Hydrogen for transportation. People have been trying to use Hydrogen for transportation for more than 50 years. These people are trying to bend the laws of physics. And there are a lot of con artists in the mix who prey on the gullible. See the convicted fraudster Trevor Milton of Nikola fame.

  • We're actually not that far off.

    Right now, liquid fuels have about 10x the energy density of batteries. Which absolutely kills it for anything outside of extreme short hop flights. But electric engines are about 3x more efficient than liquid fuel engines. So now we're only 3x-4x of a direct replacement.

    That means we are not hugely far off. Boeing's next major plane won't run on batteries, but the one afterwards definitely will.

    • > Boeing's next major plane won't run on batteries, but the one afterwards definitely will.

      Jet engines work better. Boeing's next major plane will have jet engines, just like their previous major planes.

      Synthetic, carbon neutral jet fuel will be the future for commercial jets.

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    • > So now we're only 3x-4x of a direct replacement.

      The math leads out an important factor. As the liquid fuel burns, the airplane gets lighter. A lot lighter. Less weight => more range. More like 6x-8x.

      Batteries don't get lighter when they discharge.

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    • Hmmm. If we do simple extrapolation based on a battery density improvement rate of 5% a year, it takes about 30 years to get there. So it's not as crazy as it sounds - and it's also worth noting that there are incremental improvements in aerodynamics and materials so that gets you there faster...

      However, as others have pointed out, the battery-powered plane doesn't get lighter as it burns fuel.

    • Well, there's also burning regular fuel in a fuel cell, a FCEV. That doubles the efficiencies over ICE, so I guess that bumps it back up to 8x away?

      Given the great energy densities and stability in transport of hydrocarbons, there's already some plants out there synthesising them directly from green sources, so that could be a solution if we don't manage to increase battery densities by another order of magnitude.

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    • More accurately, the calculation needs to factor in the fact that battery weight doesn’t decrease as charge is used.

      Commercial aviation’s profitability hinges on being able to carry only as much fuel as strictly[1] required.

      How can batteries compete with that constraint?

      Also, commercial aviation aircraft aren’t time-restricted by refuelling requirements. How are batteries going to compete with that? Realistically, a busy airport would need something like a closely located gigawatt scale power plant with multi-gigawatt peaking capacity to recharge multiple 737 / A320 type aircraft simultaneously.

      I don’t believe energy density parity with jet fuel is sufficient. My back of the neocortex estimate is that battery energy density would need to 10x jet fuel to be of much practical use in the case of narrow-body-and-up airliner usefulness.

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  • The energy density doesn't work for now. Everybody hoping for that breakthrough, and battery aircraft are moving into certain sectors (drone delivery, air taxis etc).

    • One of the trade offs is that engines are actually ridiculously heavy. Compact, extreme high power electric motors are starting to be commercialised. But also, fuel burns so you lose weight as you’re flying whereas batteries stay the same.

      Electric aviation is interesting but as someone who knows a bit about the industry, biofuels make more sense here.

    • Structural batteries were supposed to be the solution where the density wasn't so important. I don't really have a good understanding of the ration of fuel weight to structural weight in existing aircraft though.

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  • Biofuel makes more sense for airplanes. No conversion even necessary. You could fuel up a 737 with properly formulated biofuel and fly it now, though a lot of validation would be needed to be generally allowed especially for passenger flights.

    If we want easier to produce biofuels then LNG aviation makes sense. We are flying LNG rockets already. You could go ahead and design LNG planes now and they’d emit less carbon even on fossil natural gas. Existing turbofan jet engines could be retrofitted to burn methane.

    Biogas is incredibly easy to make to the point that there are pretty easy designs online for off grid biogas digesters you can use to run a generator. You can literally just turn a barrel upside down in a slightly larger barrel full of water, shit, and food waste, attach a hose to it, and as the inner barrel floats up it fills with biogas under mild pressure that you can plug right into things. May need to dry it for some applications since it might contain some water vapor but that’s not hard.

    Industrial scale biogas is basically the same principle. Just large scale, usually using sewage and farm waste.

    LNG rockets also mean “green” space launch is entirely possible.

    • LNG aviation does not make any more sense than H2 aviation. Even LPG does not make any sense since you neither can haul 16 bar fuel tanks, nor can you realistically maintain temperature for 1-2atm pressure. And any leak is not 'oh. look, a kerosene stain on tarmac', it's ready-made fuel-air explosion.

      On the plus side we would be able to retire airport fire engines because they would never be able to get to a crash before it completely burns out.

  • It might also be because the Japanese government works very hard to have full employment and EVs require less labor.

  • The Mirai is a fuel cell EV. There is no engine. Not sure what your point is regarding engines?

  • They are just too much in bed with big oil to want to switch, instead they spend rnd on hydrogen in order to mess up with renewables on purpose.

    • Hydrogen only makes electric vehicles look good and the only alternative. In fact, if this purposeful which I doubt, it probably helped stopped other companies from making hydrogen

> When people go out of their way to avoid common sense they should be punished.

Sounds like it was mostly just people reacting to government incentives. Subsidized markets acting irrational.

  • Politicians are conduits. Someone wanted this to happen.

    But yea, subsidies. I've been on many a call where "there's govt funding available if we shape this like x" is one of the major selling points.

    • Politics has a habit of being very insular once elections are finished.

      There will always be a strong belief in artificially changing market behaviour by simply throwing money at it and hoping it sticks. When the money dries up the public tends to go back to "what's practical and affordable?".

> Hydrogen is such a terrible idea it was never getting off the ground.

See: the Hindenburg disaster

afternote: There's the potential for an amazing pun in here, but I don't think I quite did the opportunity justice.

  • Pointing to the Hindenburg as an example of why hydrogen is a bad idea is the same as pointing to Chernobyl as an example of why nuclear is a bad idea.

    wait...

  • Ehh, the Hindenburg had a flammable skin. Barrage balloons from the World Wars were most often filled with hydrogen and yet were extremely difficult to ignite or take down even with purpose build incindiary ammo for that purpose shows hydrogen balloons can be safe. Often they would be riddled with dozens of holes but still take many hours for them to lose enough hydrogen to float back down to the ground.

    The only real downsides are slow travel speed and vulnerability to extreme storms since there arent many places to put it with a large enough hanger even with days of warning beforehand.

    • That's because regular bullets are actually pretty cold, especially by the time they reach the height of anti-air balloons.

      But hydrogen itself is SCARY. It has an extremely wide range of ignitable concentrations, and it has very low ignition energy. It also tends to leak through ~everything.

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>When people go out of their way to avoid common sense they should be punished.

You could say the same about EVs. Most people in the US who bought an EV decided to go back to ICE for their next vehicle.

> When people go out of their way to avoid common sense they should be punished.

This is the most ridiculous assertion i've seen today. You'd shut down science, for example, and innovation in general.

Why is it such a terrible idea? In theory you can generate it via electrolysis in places with plentiful renewable energy, and then you've got a very high-density, lightweight fuel. On the surface, it seems ideal for things like cars or planes where vehicle weight matters. Batteries are huge and heavy and nowhere near as energy dense as gasoline.

  • It’s horrible to work with - dangerous, embrittlement issues etc., and very energy intensive to compress into very heavy cryogenic storage containers…

    • Yeah it is so bad that it is common that rockets are launched with a hydrogen leak here or there.

    • > dangerous

      It is actually less dangerous than other fuels, for the simple reason that it is extremely light and buoyant. A gasoline fire is bad, because the gasoline stays where it is until it fully burns. A hydrogen fire is less bad, because it will tend to move upwards.

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  • Ignoring some of the other issues:

    Imagine we have this electrolysis plant, splitting up water to produce the hydrogen we need for an area. That's fine.

    But it needs fed electricity to keep the process going. Lots of it. It needs more electrical power to split the water than combining it again produces.

    So it starts off being energy-negative, and it takes serious electricity to make it happen. Our grid isn't necessarily ready for that.

    And then we need to transport the hydrogen. Probably with things like trucks and trains at first (but maybe pipelines eventually). This makes it even more energy-negative, and adds having great volumes of this potentially-explosive gas in our immediate vicinity some of the time whether we're using it individually or not.

    Or: We can just plug in our battery-cars at home, and skip all that fuel transportation business altogether.

    It's still energy-negative, and the grid might not be ready for everyone to do that either.

    But at least we don't need to to implement an entirely new kind of scale for hydrogen production and distribution before it can be used.

    So that's kind of the way we've been going: We plug out cars into the existing grid and charge them using the same electricity that could instead have been used to produce hydrogen.

    (It'd be nice if battery recycling were more common, but it turns out that they have far longer useful lives than anyone reasonably anticipated and it just isn't a huge problem...yet. And that's not a huge concern, really: We already have a profitable and profoundly vast automotive recycling industry. We'll be sourcing lithium from automotive salvage yards as soon as it is profitable to do so.)

    • It’s not even the grid, by the time you’ve done the electrolysis you’d be better off just charging a battery.

      Also, compressing and cooling a gas takes another huge hit at the efficiency. Electrolysis comes out at atmospheric pressures.

      Oh and the platinum electrodes you need…

      I’m also just now visualising a hydrogen pipeline fire… terrible terrible idea.

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  • It's hell to store. The energy density is terrible and as a tiny molecule it escapes most seals. When it transitions from a liquid to a gas, it expands manyfold (i.e., explodes).

  • Besides being expensive to generate unless you already happen to have an electrolysis plant handy, hydrogen is awkward and hazardous to store. Once generated, it costs yet more energy to liquefy, and then it seeps right through many common metals, weakening them in the process. It's just not a good consumer-level energy source, and nobody could figure out why Toyota couldn't see that.

    Interestingly, liquid hydrogen is nowhere near the most energy-dense way to store and transport it. I don't recall the exact numbers but absorption in a rare-earth metal matrix is said to be much better on a volumetric basis. [1] Still not exactly cheap or convenient, but it mitigates at least some of the drawbacks with liquid H2.

    1: https://www.fuelcellstore.com/blog-section/what-hydrogen-sto...

    • Remember that China briefly embargoed Japan for rare earth metals in 2010, and Toyota launched the Mirai in 2014. My theory was that it was developed as a national fallback for Japan in case that embargo continued or got worse. Think 1930s Volkswagen. Anyone can comment on that?

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  • Hydrogen is the minimum viable atom: one proton, one electron. H2 is a tiny molecule. "hydrogen embrittlement" is when it's small enough to diffuse into solid metal, because it's that much smaller than iron atoms.

    It's hard to work with because of this, and what's the point? For most uses, electricity supply is already everywhere.

With solar/wind oligarchs can't charge you every time you charge your EV at home

Hydrogen was meant to replace Oil so that the oligarchs can keep their oligarchy rather than "pull themselves up by bootstraps"