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My understanding is most hydrogen fueling stations produce the hydrogen onsite via electrolysis of water.

EDIT: My understanding was wrong - it's produced locally onsite but via steam-methane reforming: https://www.energy.gov/eere/fuelcells/hydrogen-production-na...

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Completely wrong.

Globally over 95% of hydrogen is sourced from fossil fuels, particularly natural gas wells. Electrolysis is very limited to niche applications or token projects.


Maybe that's what it was - produced onsite via steam extraction from piped in natural gas (which means you could just as easily burn the natural gas in the vehicle).

Either way there aren't many trucks full of hydrogen zipping around.


The electrolysis needs power and could be fueled by fossil fuels.

That’s not a thing. Anyone who’s seen hydrogen being split from electrolysis knows it takes a lot lot lot of electricity and is very slow. If two people needed to fill up in the same day it would run the well dry.

If you can do that at a meaningful rate you might as well install ev charging and just not electrolyse when cars are charging

He didn't say it doesn't have local tanks. Only that it makes h2 local. You can still make h2 to replenish, and have storage.

This is akin to how almost all power used to charge cars, is not-green. For example, there are still Ng, coal, and other types of power plants. If cars switched to gas, instead of electric charging, then some of those could be shut down.

But the true point, is as we convert to more and more solar, we'll eventually shut down the last of the fossil fuel burner plants, and eventually the cars will all be green power sourced.

Same with h2. Getting non-polling cars out the door and into people's hands, is key. Eventually, where the power comes from will be clean. And really, we're already having issues with power infra, even before AI, so re-purposing Ng pipelines for H2 would be a great thing.


We won't get rid of natural gas any time soon. Ng pipelines are not in any way similar to H2 pipelines except the word 'pipe'. You can't just put hydrogen in them. You can't even retrofit them. You're looking at laying an entirely new pipeline either way.

Furthermore, most H2 is produced by fossil fuel extraction. We aren't cracking water to get H2, we're pulling it out of the ground. Cracking water is hideously expensive.

All in all, combustion engines are more efficient than green hydrogen. That's the core problem. We simply don't have the absurd amounts of unused energy required for green H2 production. If we did, we'd be pumping fully half of that energy into the atmosphere as waste heat.

Hydrogen cars aren't going to happen. We won't have grid-scale hydrogen. It's just a terrible idea. Hydrogen is too difficult to handle and incredibly dangerous to store. The efficiency is so ludicrously bad that you would genuinely do better to create syngas from captured atmospheric carbon and burn it in regular combustion vehicles.

Avoiding carbon emissions is not the only concern in regards to the climate. Focusing on carbon and nothing else leads you to really dumb and bad ideas like piping hydrogen gas across the continent.


This is not quite true. The original gas pipes in most cities were built for "town gas" which was produced from coal and is 50% hydrogen by volume. The infrastructure could handle hydrogen just fine, but the low conversion efficiencies make it impractical.

h2 can be co-mingled with Ng and extracted with a molar filter at the other end.

Ng pipelines are everywhere, so it makes perfect sense.


None of the pipes or valves are designed for hydrogen. It will steal leak. And leaking a very flammable gas isn’t great.

Let alone the compressors or the flow measurement equipment. Also significant portions of the pipesline (especially in neighborhoods / last mile) aren't metal anymore.

Your understanding is entirely wrong.

Most hydrogen fueling stations receive it from the next steam reformer, which will make it from fossil gas.


this is the case while they're in the hype building phase, when people are paying attention

if hydrogen even gained widespread adoption, it would be mass produced via steam reforming of natural gas

(which is why the oil majors are the ones desperately pushing it)


Natural gas vehicles make way more sense than hydrogen. But they didn't survive in the (US) market outside specific fleet applications.

Turns out compressed gas fuel is a big PITA.


They were popular in Thailand and Cambodia for awhile due to domestic natural gas reserves. But after those wells began to dry up Thailand at least decided EVs were the future instead.

That makes no sense. If the oil companies were pushing H2, every car would be H2 by now.

H2 can be generated anywhere there is power. Any power that can be used to charge a car's battery, can be used to make H2. Yes, I'm sure you have 1000 reasons, but I don't really care, it's just not reasonable to discredit h2 because of made up paranoia.

We should embrace any way to get a clean running car on the road.


H2 from electrolysis is wildly expensive. H2 from natural gas is more affordable. Both are alternatives to BEVs, which are the better approach to electrifying transport. If Toyota had gone all in on BEVs when it began its H2 strategy, it would be selling more EVs than Tesla. Instead it entirely ceded the field to others, first Tesla and BYD.

H2 from electrolysis is wildly expensive. H2 from natural gas is more affordable.

Irrelevant. It seems like everyone who argues against H2 is stuck on "now". Had that been the case with battery powered cars, they'd have never got off of the ground.

Batteries were terrible, wildly expensive, extremely unreliable. It's only been the immense research poured into them, that has brought their costs down.

Meanwhile, the cost of storage on an H2 car is nothing, compared to the immense and exorbitant cost of all those batteries. Batteries which make a car extremely heavy. Batteries which cannot be charged below -20C, and require heaters. Batteries which are incredibly dangerous in car accidents. Batteries which are costly, and damaging to the environment to create, difficult to recycle, and damaging to the environment to recycle.

Compared to battery tech of any type, H2 is a dream from the gods.

Yet because there hasn't been 17 trillion dollars of cash thrown into h2 generation tech, people prattle on about how expensive h2 generation is.

And it doesn't matter where h2 comes from now. It matters where it can and will come from. The goal isn't to make sources of power to generate h2 clean, the goal is to get end-polluters, cars, clean.

If the only goal was "clean", then most electric batteries charging right now, would fail that very goal. After all, there are still coal and gas power plants this very moment, and if we pulled all electric cars off the road, those would close.

No, the goal is to work towards more and more solar power, wind, etc. And in parallel, get cars ready for the day when power they're charged from isn't polluting.

The myopic view of what I deem hyper-environmentalists, is disturbing to me. It is paramount that we don't let short sighted views fog the reality around us.

Anyone arguing 1000lbs of batteries, all environmentally damaging in their construction, recycling cost, and disposal, is superior to h2, is arguing from a pedestal of sandy, earthquake prone, unstable support.


What I don't understand is why we would use H2. It's not like batteries are not getting better all the time. Not just the getting H2 for a good price but the whole system seems so much more complicated than just using a battery. What is it that H2 can do so much better that we would even spend the time and money to develop better solutions? Tell me what is the killer feature?

Because it must be a really killer feature to justify wasting about 50% of the electricity you put in and developing a distribution network and building cars that can handle H2 and even using the H2 for driving instead of steel mills or other places that might need green H2. Not to forget about the hassle of refueling with gasses that is totally different from a normal gas pump where you have to create a high pressure seal and the handle gets to cold to touch.

Also comparing a technology that will be only useful in many years with the battery technology from today is an odd choice, to say the least. Not only is the content of problematic materials constantly shrinking, the number of batteries that need recycling is currently so low that there is very little need for a big industry. But it is very likely that just like with the classic car battery recycling the more recent batteries will definitely be stripped for their precious materials.


What I don't understand is why we would use H2.

You're asking questions that were answered in the very post you responded to. You're also simply inventing costs, such as 50% power loss.

What is the precise cost? You don't know. If you research the precise cost, my post discusses "what about the future after research", but this upsets you too.. for, researching things is a waste, you say.

(Even though you realise h2 is used elsewhere, and any improvements would help those industries?!)

For power, a real world example is that charging a car, tends to result in ~15% power loss. Some is converted to heat. There is also power loss in keeping the battery warm, when it's cold out (-20C). There is power loss when it is very hot outside, when draining the battery too. There are also transmission costs related to power infrastructure, upwards of 15%. When generating h2, the stored gas is simply transported as is, 30% plus loss of gas seems unlikely.

Batteries also age, and as they do, they are less and less efficient at discharge/charging. They lose range:

https://www.slashgear.com/2008627/tesla-owners-reported-batt...

Losing significant capacity is unhelpful for range. Further (same article), most car companies recommend not full charging on a regular basis, to extend battery life. So you lose range over time, and you're not really supposed to charge to full. Great. So much for that range!?

You ignored my comments on recycling, by simply saying there aren't many batteries to recycle?! This is an absurd response, absolutely absurd. The point is adoption, and every car requires recycling at end of life. We're comparing car tech side by side, and your response is "well there's only a few of these horribly polluting battery cars!". What? Recycling a horribly polluting tech is just that. It's amazing how the most environmentally conscious among us, simple ignore that electric cars are cesspools of 1000s of pounds of polluting materials.

Lastly h2 works perfectly right now. It is useful right now. It has range as long as electric cars.

These are the sort of arguments that are constantly leveled against h2. Ones without any real research, with made up figures, and not comparing battery tech in the same light. Ones ignoring the downsides.

If people had this attitude when modern battery based cars appeared on the market, no one would have tried a single one.


> What is the precise cost? You don't know. If you research the precise cost, my post discusses "what about the future after research", but this upsets you too.. for, researching things is a waste, you say.

>(Even though you realise h2 is used elsewhere, and any improvements would help those industries?!)

It doesn't upset me but I am struggling to see the killer argument for H2 right now. The cost I am talking about is the cost of researching improvements at this exact moment and the cost of rolling out H2 infrastructure. I can not name them but they are probably not small.

> For power, a real world example is that charging a car, tends to result in ~15% power loss. Some is converted to heat. There is also power loss in keeping the battery warm, when it's cold out (-20C). There is power loss when it is very hot outside, when draining the battery too. There are also transmission costs related to power infrastructure, upwards of 15%. When generating h2, the stored gas is simply transported as is, 30% plus loss of gas seems unlikely.

The 50% I am talking about is a very positive estimate of the "well to wheel" efficiency of H2 in a car right now. From what I read about 30-50% of the power needed to produce the H2 is available to the car. As far as I read the efficiency of BEV is more around 70-85%.

> Batteries also age, and as they do, they are less and less efficient at discharge/charging. They lose range

H2 tanks and fuel cells also degrade over time and that doesn't just mean that they have less capacity that means they have to be replaced because they get very dangerous. Both should hold for the lifetime of the car though. There was study recently that car batteries last longer than we assumed: https://www.dekra.com/en/batteries-of-electric-cars-are-more...

I do cede that very cold or very hot weather will harm range and that a H2 car has more range than a BEV car. I don't think though it is significant enough though (from what I read about 100 miles more). There is though the thing that batteries are getting are getting better. Less harmful and rare materials, better density, less susceptibility to temperature. So there is the distinct possibility that the problems you mentioned might be solved before H2 even gets to the point that it's downsides are addressed. That is what I meant when I was talking about the viability of researching H2 (for cars). It might be too far behind in adoption at this point to catch up to even make sense spending time on it.

It is good to keep in mind that BEV has and had a lot lower barrier of entry. H2 fueling will never work without specialized fueling stations. That means a hassle for the owner of the car and for the potential owner of a fueling station. As a society we went through the hassle of building gas stations everywhere and figuring out how to store and transport the fuel once. It is very unlikely that we have to do that again when there is another solution that doesn't need that. Power infrastructure is already widely available even though some upgrades might be necessary. You can charge your BEV on a normal outlet at home if time is not important.

> You ignored my comments on recycling, by simply saying there aren't many batteries to recycle?! This is an absurd response, absolutely absurd. The point is adoption, and every car requires recycling at end of life. We're comparing car tech side by side, and your response is "well there's only a few of these horribly polluting battery cars!". What? Recycling a horribly polluting tech is just that. It's amazing how the most environmentally conscious among us, simple ignore that electric cars are cesspools of 1000s of pounds of polluting materials.

I didn't mean to ignore what you said but the problem is currently that to build recycling infrastructure you have to have batteries to recycle. Most BEV cars and their batteries are still on the road. Even crashed car batteries often get a second life as home storage. There is development though regarding the recycling.

https://insideevs.com/news/787778/ev-battery-recycling-growt...

> Lastly h2 works perfectly right now. It is useful right now. It has range as long as electric cars.

I'd say we have part of it. We have a way to produce H2, we have a way to create electricity from H2 but we don't have a huge overproduction of H2, we don't have a distribution network and we don't have any widespread interest. From my point of view it only makes sense to even think about H2 in cars when we have enough green energy capacity to satisfy the industries that need H2. The previously mentioned inefficiencies in converting electricity to H2 and back mean that we need to deploy much less renewable energy sources before reaching a net neutral goal.

What BEV has now is moderate momentum and it's why I am asking for the killer feature of H2. Because whatever it is it must be so good that it overcomes the downsides of H2 as well as the momentum of BEV. In the end I do not care about what kind of power storage we use as long as it gets us to not use fossil fuels anymore and that as fast as possible. I am skeptical though if it is a good idea to split investment and research now when time is of the essence.

I don't know if I need to say this but am looking at this from a strictly zero emission standpoint. That means I don't consider H2 from natural gas as relevant.


You raise dying some good points, but hydrogen is really hard to store. It leaks out of everything. You have to very carefully design three containment vessel in order for it not to go wrong.

A statement predicated upon truth, but exaggerated and expanded with everty repeated retelling.

It's a solved problem. It's not an issue.


How is it not an issue? The physics of hydrogen being one proton and one electron means it gets through everything, so something that's air tight and water tight still won't be hydrogen tight. So then you have to be extra careful with every coupling and fitting in order for it to be transferred. By "solved" you mean "if we do everything right, it works", which sounds like it'll be a total failure in the sloppy messy real world where things get kinda shitty but you still need them to work.

But isn't that a counter point? Just putting the electricity directly into a car seems sensible instead of converting it to H2 and then back to electricity. Especially now that wo don't usually have a huge oversupply of green energy. We can think of ways to use the oversupply when it really becomes a problem. But I'd assume then BEV will be so dominant the no one will go through the hassle of supporting H2.

> We should embrace any way to get a clean running car on the road.

Only if it's also feasible to fuel that car in a clean way.

And looking at where the hydrogen would come from is not "made up" or "paranoia".


It is entirely feasible. And it is made up to claim that "Well, this second it looks like there's no infra for green h2, so it can never happen! So there!"

If that was the case, we'd still have electric cars with 50km range, and 1000lbs of batteries.


I haven't seen any cost models where green hydrogen is feasible without a lot of super cheap excess electricity. And those situations also boost batteries. Do you have one you can show me? It's not just lack of infrastructure, even if you solved the problem of building everything out green hydrogen is still not worth it under conditions close to the present day.

And I didn't say it could never under any circumstances be feasible.

> If that was the case, we'd still have electric cars with 50km range, and 1000lbs of batteries.

I don't follow your logic here. Nobody went out and built tons of lithium ion batteries for cars until they were actually feasible. We're living in the world where companies wait, and it worked out for electric cars.


Research. Battery tech was terrible. Horrible. It was only through endless research, trillions spent, that battery tech can do what it does today.

Now apply the same logic to h2.


I didn't suggest stopping research.

But while research and scaling up made batteries 50x cheaper, batteries are mostly about material costs and technique. For hydrogen there's a huge per-unit energy cost and that limits how much research helps.


say you're Shell

you are vertically integrated, you have billions invested in oilfields, refineries, distribution, and the retail channel ("gas stations")

if transport switches to electric, what's your role?

answer: there isn't one, you are completely redundant

but what if hydrogen took off instead?

if you produce via electrolysis, you only keep the retail channel

but if you can get H2 established, then you can do a switcheroo and feed in H2 produced from your existing natural gas infrastructure, and massively undercut everyone's electrolysis business

at which point you're back to the old days, just instead of selling gasoline from your oilfields, you're supplying hydrogen produced from their gas

... and that's exactly what they're trying to do


There's no point. EVs go 50% further on the same amount of energy, are easier to charge and are, of course, cheaper.

EVs take forever to charge, rendering long trips unrealistic. They are not cheaper long term, for they rely upon thousands of pounds of heavy batteries.

If they go further now, that is not a given down the road.

Were you to employ this logic when electric cars first came out, there wouldn't be a single one on the road. It's only through trillions of research dollars, that current battery tech is where it is.

But sure, let's not work on multiple paths. Let's discount other attempts at clean tech. Even if they're older, cost less to the environment to build (batteries are terrible, environmentally), and so on.


> EVs take forever to charge, rendering long trips unrealistic.

You'll find EVs that will go 700km+ with just one, 15min stop, as they charge at over 350kW in this day and age:

https://ev-database.org/#group=vehicle-group&av-1=1&rs-pr=10...

You'd want to make that 15min stop at least once on such a trip. Or fly instead.

> It's only through trillions of research dollars, that current battery tech is where it is.

Problem is that while batteries only needed scale and improvements in manufacturing processes to become cheaper, there's no such path with hydrogen.

The tank and the fuel cell are inherently expensive. The fueling station costs literally 10x that of a fast charger and in this day and age doesn't even charge faster as while the first customer will be done in less than 15min, the next needs to wait for the system to repressurize and that takes time. Also it goes kaboom if it fails, which is something we know, because it already happened. The fuel itself cannot be cheaper than electricity unless you want to make it from natural gas, in which case you better just use that instead.

> (batteries are terrible, environmentally)

The sheer energy that's wasted by a hydrogen car vs EV over its life cycle is enough to produce and safely dispose of a battery.

And this is what it really boils down to: hydrogen is not energetically efficient, therefore you can't make it cheaper unless you use fossil fuels. We already have fossil fuel cars.


There is only one car in that database that has even close to a 700km range on long trips, and that is only under perfect conditions.

As with any car, you don't wait until out of fuel to recharge. Instead, you seek to do so well before. These pages at least understand a little of that, and cite a real-world range under perfect conditions of 450km before recharging, with a range of 300km afterwards.

Yet these figures are with no heat or AC, with it not below -10C, and with an incredibly slow speed of 110km/hr, which is illegal on some freeways in the US and Canada (yes, too slow on a freeway is illegal). At least, according to this page.

And yes, this is a "long trip" after all. I often have circumstances where I drive 1600km a day.

For current situations, although the future can be different, if you click on the details, it's actually 22 minutes to get an 80% charge, and of course with 400kw thrown at it. You have to get to the charger, hope one is free, then start this business. Just the on/off plus charging would realistically be 30 minutes, and taking 1 1/2 hours off to charge is ridiculous.

The current real world problems are, you'll never find that level of charging anywhere along the route of your long trip. Not with assurances it actually works, and that you don't have to redirect 100s of kms out of the path you wish to take. I cite current, because the future is just that. However, you'll literally have to spend trillions on infra just to do anything more than that, because if you're having literal parking lots full of cars charging at turn-offs on interstates, that's going to require massive, new long-haul electricity infra.

Which is really the point. Very slow to charge, hard to get charged, and once the infra is in place, there's still issues. Like recycling. And weight of car. And peak demand vs storage (such as with h2). And more.

Each tech stands poorly against gas cars, in terms of usability, reliability, range, fueling issues, and so on. That's to be expected though, with over 100 years of relentless development of carbon beasts, in planes, ships, cars, engines of all sorts.

It will take decades at the very least to get as good with electric in any form.

Yet what do I hear and see?

What madness do I see relentlessly spouted?

That one tech is the only answer, that R&D will change nothing, that even though range is an issue, the person is the problem, not the range, and so on.

Like the crass "use an airplane" comment.

Ah well.


> I often have circumstances where I drive 1600km a day.

Do you not do stops? The ranges I've shown include a 15min stop to recharge.

Anyway, I used to do such trips regularly. Covered over 100k km like that. I still did stops every ~400km because a man's gotta eat and, more importantly, wee.

Also sleep, because after a few close calls caused by 18h+ of driving I figured it makes more sense to find a hotel after 1200km or so.

Overall, current-day EVs and infrastructure wouldn't add more than 30min (if anything at all) compared to a combustion car if I were to do the same trip today.

In hindsight I should have flown and take taxis at my destination - would have been cheaper.

My view is that you're arguing about a non-issue, because the small minority that actually runs down a full tank before stopping is endangering others and being unkind to their bodies.


Do you not do stops? The ranges I've shown include a 15min stop to recharge.

The ranges you showed were inaccurate, for the reasons I cited, including 22 minutes to charge under only special circumstances, with super special very rare chargers.

When I stop to refuel a car, I put fuel in and drive through. I urinate often on the side of the road, or (what takes 2 minutes) while the car pump runs.

Driving 1600km is under 12 hours driving, including those stops. No I'm not tired or lacking in focus at the end of that time. It's only 12 hours.

You'd need to recharge three times time make that range, or 22 minutes * 3 plus the fact (which you are ignoring) that you can't drive where ever you want and get that speed of charging. No way.

If you think driving for a few hours is dangerous, you are completely out of it.

This is the problem with these discussions. People sugar coat all the issues, and pretend they don't exist.

And this isn't even a conversation about "use fossil fuels". Oh no. This is "you'd better use MY green tech, or you're nuts! and I don't want you to even try another tech, how dare you!"

The more options we have, the better.


> But sure, let's not work on multiple paths.

The article is about a sign of failure of one of the multiple paths that was pursued by Japan and Ca State subsidies that was attempted over the last 20 years.

You can work on multiple paths, but to not measure and adjust defeats the purpose.


Pumping gases is not really fast. That goes for H2 or natural gas. It pumps slowly as to not overwhelm the tank and it needs time to equalize after the pump. Also connecting the nozzle is much more of a hassle because it needs to be a tight seal. Not remotely comparable to pumping gasoline.

Apart from that a modern BEV can charge pretty fast. Just enough time to get a snack and eat it.


You've been told why that time is longer than you think, and why it hurts long distance travel. Ignoring that in your reply isn't helpful.

This conversation is about R&D too. Batteries used to take forever to charge. They're better than they were. But I guess h2 can never improve, ever? And all these made up "hassles", oh no, you have to plug the nozzle in right? How tiresome! And I guess they can't insulate the handle? And the speed, well it takes hours to pump? All made up problems.


You are right. These are things we might overcome. The question is if it's worth it. BEV is here, has a superior charging network and some inertia.

Apart from that I find it a bit unfair to compare today's BEVs with tomorrow's H2 cars.


>We should embrace any way to get a clean running car on the road.

No. We should embrace the technically most feasible, which opens up new technology to the most people.

EVs are the clear winners. Every cent spent on hydrogen infrastructure is a cent wasted, because it could go to making the one feasible technology better. Arbitrary openness to technology long after it has been clearly established that the technology is inferior is not a good thing, it is a path to stay on ICEs forever.

Hydrogen is a bad idea. The only way to defend it is by pretending modern EVs do not exist, since they solved all the existing problems and offer numerous benefits over hydrogen.

Additionally the customer has already chosen and he has chosen the right technology, because the value proposition of an EV is far greater than that of a hydrogen car.


Okay not driving it around then. But somehow it's worse. You still have to build the special tank and the special pump and also get an electrolysis device that is big enough to create enough hydrogen and also you have to get heaps of power somewhere that could instead be just straight put into a battery in a car. Make it make sense. What's the point? Who is willing to do that?

Don’t forget keeping everything cold enough.

On the vehicle side, you can make a gasoline tank in pretty much any shape you want. We have lots of experience making batteries in different shapes thanks to cell phones.

High-pressure tanks only want to be in one shape. And it’s not especially convenient.


Is the shape round? I bet it's round.

No need as I have shown in my other coment.

Ultimately, it's shrapnel-shaped.

Is that shrapnel arranged in a roundish pattern?

One of the reasons we use cryogenic liquidfied gases is so the density can be in the same ball-park of more-easily liquified gases which do not need low temperature to keep from expanding until the tank ruptures.

>One of the reasons we use cryogenic liquidfied gases is so the density can be in the same ball-park of more-easily liquified gases which do not need low temperature to keep from expanding until the tank ruptures.

Propane, butane, LPG are all gases but the pressure which needs to be contained as the gas is turned into a liquid using pressure, is not too high for the typical welded BBQ tank. Designed to hold about 350 psi.

The two lighter hydrocarbons, methane & ethane can be compressed way beyond what a high-pressure spun cylinder (like the typical 3000 psi rated heavy oxygen tank welders use) can handle, and still not liquefy.

So similar to oxygen, nitrogen, argon, hydrogen and other "fixed" gases, methane needs to be liquefied cryogenically or any reasonable size tank will still not hold enough to last but a very small fraction of the time compared to the same capacity cryogenic storage.

But "storage" is doing a lot of work here.

Interestingly, with cryogenics you're going to need to handle even less pressure than the BBQ tanks, and the same size container ends up holding way more than the high-pressure cylinder at 3000 psi.

A typical liquid nitrogen cylinder runs at about 50 psi, the tank will be rated quite a bit higher than that but not considered "high-pressure" by anybody. Thinner and non-curved shapes can be fine which can be lighter in weight than higher-pressure ratings would require, but you really have to have plenty of good thermal insulation to boot.

The thing is, once you refill your cryogenic tank with cold liquid gas, you can never actually shut the tank completely. There is no additional cooling. The only thing keeping it cold is the low temperature of the liquid itself, no matter how good the insulation is, heat will gradually soak in and given enough time the whole thing would eventually end up at ambient temperature. Not cold enough to remain as a liquid any more.

That would be eventually explosive whether it was a flammable gas or not.

Instead, the tank is continuously venting a constant stream of gas from top.

IOW the rate of heat absorbtion is compensated for under equilibrium as it boils the liquid a little bit constantly and there has to be a way for that gas to escape. The remaining liquid maintains the low temperature because the boiling point of the gas (at that low pressure) is still in the cryogenic range.

The liquid self-refrigerates by evaporation to the (negative) boiling point of the substance. Which is why liquid helium is so much colder than liquid nitrogen in an identical cryo tank.

That means if you fill a tank with one of these cryo gases, depending on your usage rate the losses to evaporation may be more than the amount you are utilizing.

Or if you fill the cryo tank and don't use any at all for a while, it will empty itself by evaporation anyway and it could be before you got to use any of it.


> battery

Batteries create a lot of toxic waste. I'm willing to live with that if it doesn't cause climate change but there is an advantage to hydrogen? What is the impact of H2 fuel cells?


Batteries do not create a lot of toxic waste and are essentially fully recyclable.

The lead in automotive lead acid batteries today is almost entirely recovered and remanufactured into new batteries.


Isn’t this bad? This means H2O molecules are being destroyed and the water is not returning to the water cycle to be reused. We will literally run out of water if everyone did this.

Water gets split into oxygen and hydrogen using energy. The hydrogen then gets burned to release usable energy, which creates water. At least as far as I remember from chemistry class ages ago.

There's some truth to what the gp said. Some hydrogen will escape, enter the upper atmosphere, and be blown away by the solar wind and thus be permanently lost.

I assume that this has been happening to all gases in the atmosphere for aeons, and thus, while technically correct, it is completely negligible for the relevant time scale.



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