> I'd say you're being deliberately ignorant here, but I'm really not so sure. A gas turbine spins rapidly, putting huge stresses on the blades. They also operate at extremely high temperatures.
Seriously, your projection is out of control here. A gas turbine burning hydrogen does not experience any stresses that is meaningfully different from one burning natural gas or kerosene. Simply applied engineering can solve all of the issues associated with hydrogen gas turbines.
> A gas turbine burning hydrogen does not experience any stresses that is meaningfully different from one burning natural gas or kerosene. Simply applied engineering can solve all of the issues associated with hydrogen gas turbines.
Did you misread that comment? The point was that hydrogen's application in the chemical industry don't involve turbine blades spinning at extreme speeds at high temperatures.
Yes, the principle of combusting a gas, driving a turbine with the expanding gas, and using that turbine to drive a compressor is the same. That doesn't mean you can just feed a gasoline powered turbine hydrogen and be done with it. The turbines that can run hydrogen today can only run a small portion of it.
> The challenges of using hydrogen go beyond body shape, though. Redesigning a turbine engine to run on the stuff will be a multi-billion-dollar endeavour. Hydrogen burns faster than kerosene, and also burns hotter. That means materials exposed to its combustion experience greater stresses. It also risks increasing the pollution generated in the form of oxides of nitrogen, which would partially negate the environmental benefits of burning hydrogen. And it would be useful as well to arrange matters so that some of the energy used to compress or liquefy the hydrogen for storage could be recovered and put to work.
The Soviets built a plane that flew on hydrogen, but it only completed 100 flights. And only part of those were with hydrogen, the rest were with natural gas: https://en.wikipedia.org/wiki/Tupolev_Tu-155
> The Soviets built a plane that flew on hydrogen, but it only completed 100 flights. And only part of those were with hydrogen, the rest were with natural gas: https://en.wikipedia.org/wiki/Tupolev_Tu-155
So you admit this has been done since the 1980s? You seriously don't think we can improve on 33 year old technology?
How dishonest are you going to get before you will admit you were wrong?
It was done for a very short duration during the 1980s as a technology demonstrator. A prototype, not an actually commercially viable product. Yes, we can improve on a 33 year old technology, but it's not something we can just buy off the shelf. GE thinks it'll take until 2045 to make turbines that run off of 100% hydrogen.
> How dishonest are you going to get before you will admit you were wrong?
When you show me where I can buy a gas turbine that runs off of hydrogen. Not a gas turbine that runs mostly off of natural gas with a little bit of hydrogen mixed in. Not a press release of a company saying "we have experience with hydrogen turbines". If you're going to say that hydrogen gas turbines are off-the-shelf then show me the shelf off of which I can buy it.
> Take the Gibraltar-San Roque oil refinery in Spain, where the GE-made 6B.03 turbine has logged thousands of hours burning a blend of fuel gas and hydrogen. This same 6B.03 machine is also working in a South Korean refinery, where it has racked up more than 20 years burning a fuel blend containing more than 70 percent hydrogen. This turbine has even gone all the way up to a 90 percent hydrogen blend.
So even your goalpost moving argument is still wrong.
This whole thing started because no one here thought someone would seriously try to argue that hydrogen gas turbines are impossible. For some of us this was too obvious to even bother trying to debunk.
You pretty much did say that anything above 30% concentration would destroy any gas turbine, nevermind this whole goalpost moving argument of "current gas turbine already in existence." Like I said, it's time to admit you were wrong, assuming you are capable of that at all.
> Those gas turbines you're referring to can simply be modified natural gas gas turbines. The only limiting factor would be electrolysis, but that is already something people are planning to build a lot of.
This is wrong, we'd have to build new gas turbines to run on a 100% hydrogen mixture in addition to building electrolysis capacity. At this point I think it's clear you're not interested in engaging honestly, and in the other thread you'e already started to throw around ad-hominem insults [1].
So how else we're suppose to interpret this statement: "No, hydrogen rapidly corrodes any metals that it comes into contact with. If they are interchangeable, expect drastically smaller service intervals."
And if you read actually my statement carefully I didn't say that it had to be an existing, already built gas turbine. Only that we had to modify gas turbines intended for natural gas for hydrogen. Either new or existing, this isn't a hard challenge, especially considering that we replace old turbines all the time.
And you still seem unaware that even your goal-post moving argument is wrong. We really can just run existing gas turbines at 90% concentration for years on end.
> So how else we're suppose to interpret this statement: "No, hydrogen rapidly corrodes any metals that it comes into contact with. If they are interchangeable, expect drastically smaller service intervals."
I'm not sure why you're having trouble comprehending it. Existing gas turbines are meant to run on either oil or natural gas, not hydrogen. In addition to corrosion, hydrogen burns hotter.
You cited one specific turbine model that had a peak hydrogen mixture of 90% (average was 70%). Ignoring the fact that you're picking one specific model that's being highlighted for it's ability to accept hydrogen fuel, this still isn't viable for a carbon-neutral storage system since it still burns natural gas. No, we can't just run them at 90% for years on end because that will still advance climate change.
> Either new or existing, this isn't a hard challenge, especially considering we replace old turbines all the time.
It's good that you're admitting that it's not a simple matter of modifying existing turbines, and that new turbines have to be developed. But it is an additional bottleneck, it's not just a matter of electrolysis we also have to build the generation infrastructure to turn that hydrogen back into electricity.
Likewise if you interpreted my original comment as saying that it's impossible to run a gas turbine with hydrogen that is indeed incorrect. Though I'm rather unsure of how you reached this interpretation given that I even provided an example of a soviet experiment with hydrogen jet engines (albeit with significantly shorter flight time).
Why would it count in the context of climate change? It's still emitting carbon dioxide into the atmosphere. And again, this is one specific model. Many gas turbines are only capable of much smaller concentrations: https://www.siemens-energy.com/global/en/news/magazine/2019/...
You're going from "we can just run existing gas turbines with hydrogen" to "this one specific gas turbine can use mostly hydrogen fuel but still needs 30% natural gas". Again 90% was peak not average hydrogen concentration.
Companies are looking at developing natural gas turbines that run on 100% hydrogen. But they're targeting 2030 or 2040. Are you going to tell GE and Seimens to shove their head up their ass, too?
Even more moving of the goalposts... Now it's every single gas turbine out there needs to be upgradable to 100% hydrogen, and "peak" blends don't count.
Keep fucking that chicken.
Hell, your own source says:
> Similarly, the goal of 100 percent hydrogen combustion capability will be achieved step by step, test by test. “With hydrogen-fired gas turbines we can easily avoid the ‘valley of death’ where brilliant inventions die before they even scale to full potential,” says Larfeldt. “The same turbines can be used with different percentages of hydrogen in the fuel mix, with brown or green hydrogen. Existing gas turbines can be retrofitted to the latest standards. It’s an organic evolution.”
The goalpost never moved. If you want to use hydrogen storage in a carbon neutral grid you need 100% hydrogen fuel. We're not there there yet. And we won't be there for the better part of a decade, or longer.
I guess I'll keep "fucking that chicken" along with GE and Siemens and the companies that actually build gas turbines.
Why? Electric cars don't use a mixture of gas and batteries. Those cars do exist and we call them "hybrids". But those are not carbon neutral and we don't pretend they are.
An electric car is as green as the grid that powers it. But a hybrid will never be green even if the grid is 100% green because it still burns fossil fuels. Same with a turbine that consumes a mixture containing natural gas. If your generator uses fossil fuels it's emitting carbon dioxide.
And there's not a single grid that's green, since they all produce CO₂. Even zero emissions grids like wind and solar still produce CO₂ during manufacturing.
And remember just how far up your own asshole you are with this: You've reject 90% hydrogen gas turbines, future gas turbines of only nine years from now, or even steam power plants running on 100% hydrogen. At this point your rationale is so dishonestly unfair it allows zero wiggle to justify any kind of electric cars. So time to admit you were wrong, not red herring your way out of this.
That link you provided doesn't encompass gas turbines. Gas turbines capable of burning hydrogen do exist, but only at smaller concentrations, 70% methane and 30% hydrogen or less.
In addition to what I said in the other post regarding gas turbines, you also don't need a gas turbine to generate power. As long as you can boil water the rest follows logically.
Honestly, you should learn some thermodynamics and chemistry before accusing others of being ignorant.
Right, but then we're not talking about combined-cycle gas turbines to convert hydrogen back into electricity. If we're going to boil water than that's much less efficient than the ~66% efficiency we get out of combined cycle gas turbines.
Also, in case you weren't aware a combined cycle turbine also involves boiling water and spinning a turbine. The reason why they're so efficient is because energy is extracted both from the gas turbine (basically a jet engine) and a steam turbine driven by the heat from the exhaust from the gas turbine.
>Honestly, you should learn some thermodynamics and chemistry before accusing others of being ignorant.
Sure, we could burn hydrogen and drive a boiler like a coal plant. But that's not where this comment thread started.
> Those gas turbines you're referring to can simply be modified natural gas gas turbines
Sure, if you just want to run them for a short period of time and generate a lot more wear. If these turbines are so simple to modify, why does GE say that it won't be until 2045 that their turbines will be able to run 100% hydrogen gas?
Then repurpose old coal plants for the same reason. None of this needs to be hard.
This whole debate started when you were caught making ignorant statements regarding basic chemistry and thermodynamics. You're not going to win by just doubling on everything or moving goalposts. It's past time to admit you were wrong.
> Those gas turbines you're referring to can simply be modified natural gas gas turbines.
> It's past time to admit you were wrong.
Follow your own advice. You can't just feed a gas turbine hydrogen and run it as normal. Existing gas turbine manufacturers don't plant to offer 100% hydrogen gas turbines for decades.
You repeatedly, outrageously violated HN's rules in this thread. I've pretty much seen it all here and even I was shocked. However wrong someone else is or you feel they are, you absolutely cannot post like this on this site.
Although both of you were at fault, your comments were so aggressive and vicious that I've banned your account. If you don't want to be banned, you're welcome to email hn@ycombinator.com and give us reason to believe that you'll follow the rules in the future. They're here: https://news.ycombinator.com/newsguidelines.html.
Super-capacity is going to be a major driver for the build-out of water electrolysis for the production of hydrogen. You can turn what will basically be a waste product into a highly useful fuel. I've seen people contend that this will be expensive, but given the very cheap input costs I believe this will be a very cheap process.
No, you have salt caverns with a volume sufficient to accommodate a lot of hydrogen. Actually implementing such a solution involves massive scale electrolysis, and either massive scales of oxidation cells or gas turbines designed to burn hydrogen. Neither of these things have been done at anything remotely close to the scale required to make renewables feasible.
Back in the 1950s people thought that nuclear power would be effectively free. But actually building it at scale exposed challenges of implementation that weren't foreseen. The cost of a system on paper and the cost after overcoming the challenges of actually building it are two very different things. For hydrogen storage, you only have the former.
Those gas turbines you're referring to can simply be modified natural gas gas turbines. The only limiting factor would be electrolysis, but that is already something people are planning to build a lot of.
Nuclear's problem are fundamentally political in nature. If we really cared about green energy, nuclear power could easily be built out at scale.
> No, hydrogen rapidly corrodes any metals that it comes into contact with.
The industries that manipulate tens of millions of tons of hydrogen each year would be astounded to hear this statement of yours. What are those facilities made of, unobtainium?
A claim which simply isn't true. Only certain alloys have a problem with hydrogen. We've been using hydrogen in industry for decades and most of this problem has been solved.
We've been using hydrogen in the chemical industry. We haven't been using hydrogen to drive combustion turbines very much, and even then it's in a mixture of natural gas.
Since synthetic fuels are zero emissions, why would they ever need to be replaced by EVs? A better question is why we need to bother with electrification at all if there are alternative paths to zero emissions?
Particulate emissions can come from the tires. EVs aren't magic on this form of pollution. Plus, you can have particulate filters on the engine exhaust, reducing this greatly.
I wouldn't be surprised if ICE's powered by biofuel/synthetic fuel could be competitive with electic veichles given enough time to improve the technology. Most likely we are going to see some of that development as EV's simply cannot fill all the niches yet.
The fundamental problem is that EVs might be doomed once fuel cell cars come around. Nearly all of the criticism of this argument are just a mirror of the arguments against EVs (often made by pro-EV people no less).
So the real misunderstanding isn't with anti-EV people, but with pro-EV denying that there's a future beyond EVs.
Fuel-cell proponents keep claiming they're just around the corner but the issues with them are fundamental. ~3x the total energy use because of all the inefficiencies, and needing an all new infrastructure compared to BEVs where the grid is already everywhere. If FCEVs show up and are actually usable that would be fine but I wouldn't bet on it. They're mostly brought out as an argument for staying on ICEs until, real soon now, we'll finally have them. Maybe for long sea shipping hydrogen will work, but even for trucking the 3x energy input needed is hard to justify.
There's nothing stopping FCEVs from being as efficient as BEVs. Even now, huge improvements are being found like 90% efficient electrolysis[1]. Future improvements in hydrogen and fuel cell technology could close the gap entirely.
Like I said, you're repeating many arguments that are a mirror of the arguments made against BEVs. It's pretty ridiculous to just repeat anti-EVs for something else while being pro-EVs.
The other thing is that this viewpoint is increasingly outdated. A lot of these "facts" date to the 2010s or earlier. These are more inline with a person being out of touch than someone that is informed.
90% efficient electrolysis doesn't matter when "getting hydrogen from the pump to your car's fuel tank" has 20+ percent energy losses. And from the tanker trailer to the pump. And...
This comes from the inherent thermodynamic inefficiencies of compressing something, letting it expand, and then compressing it again.
Those losses can be made much less than that. Theoretical minimal losses are on the order of 1-2kWh per kg, and in practice not much more than that[1]. Further efficiency improvements can get reality even closer to theoretical.
Most of these arguments are increasingly outdated, as I mentioned before. We're at the point where hundreds of billions of dollars are being spent on hydrogen right now[2]. So naysayers are more accurately described as being out of touch with latest events and not people with any special knowledge.
I think fuel cells window of opportunity is closing fast and they have no traction despite a lot of investment.
EV's weight penalty is going away as battery energy density relentlessly increases. EV's capital expense penalty is also going away due to mass manufacturing improvements.
Charging infrastructure for EV's is basically a last 50 foot problem. Running 30 amp 240 circuit from a breaker box to an external outlet. Compare with the infrastructure needed for the 'hydrogen economy'. Every bit of it needs to be designed and built from scratch. Countries have built stuff like that but it takes decades. We don't have decades.
You can't build a "lead" as if this was a race. For one thing, there's no finish line. There's nothing stopping fuel cell cars from having their own technology revolution and a S-curve like adoption curve that displaces everything else. This could happen ever after EVs "win" over internal combustion so to speak. It's fully possible that EVs are still on-track to being replaced no matter what happens next.
The other thing is that we still have to pay attention to fundamental limitations. There are hard limits to battery energy density that likely to never be crossed. Extremely fast-charging will probably always be limited by its high power power draw. Meanwhile, fuel cell technology is advancing extremely quickly in its own right. We could be seeing fuel cell cars that cost as much as a Corolla[1], and cost only $1.5/kg[2] to refuel (or about 2-3¢ per mile). In a world were fuel cell cars cost <$20k and are cheaper to run than EVs, while also delivering 400 miles of range and 5-minute refueling times, EVs quickly lose much of their luster.
There is still a hard limit to hydrogen energy density that is likely to never be crossed. And safe consumer-friendly handling of pure hydrogen is much more expensive than electricity, that also stems from physical limitations. These limitations are being hit now. On the other side, batteries and chargers did not hit their hard physical limitations yet. Supercapacitors exchanging many megawatts of energy over superconductive wires are feasible.
Hydrogen energy density is around 39,000 Wh/kg. That's rarely going to the limiting factor. The physical limitations are nearly the same as natural gas, which is to say they are easily solvable. Superconducting wires will have their own major issues that are a long ways away from being solved.
In reality, we're nearly at the point where hydrogen is a solved problem, but batteries will be a very long ways away from being a car for everyone. In particular, you've ignored the limits on battery energy density which will likely limit battery powered cars to either expensive luxury cars or short-ranged urban cars.
You conveniently omitted the storage vessel factor from the energy density. And it's definitely not comparable to natural gas in other respects too, such as hydrogen is corrosive and needs special alloys or nonmetal materials.
Superconducing wires are already and increasingly used in practice. Even without superconductors we can just keep raising the voltage and use copper, there are new silicon carbide power transistors that make it possible. We aren't near physical limit yet.
Other assertions of yours are likewise unfounded, too.
I can totally see hydrogen airplanes but for cars it's too little too late.
From a theoretical standpoint, you don't need to worry about that. You can conceive of metal hydrides or other forms of dense hydrogen storage. Even as LH₂, you're still looking at around 2700 Wh/L of energy. That's well beyond any known rechargeable battery.
And the "special alloys" really just mean certain types of steel alloy, and "nonmetal materials" really mean certain types of plastics. This is not a big challenge.
You still need very low temperatures and exotic materials for superconducting cables. Not to mention the power generation needed to sustain that level of power draw. This is a long-term problem that we're nowhere near solving.
As I said before, this is not a race and there is no finish line. There's nothing stopping fuel cell cars from displacing EVs at an arbitrary point in the future.
As soon as everyone agrees to build more nuclear power... We're not anywhere near ready to use anti-matter, but the next best thing faces extreme opposition for some reason.
Hydrogen is pretty much a solved problem too. Most of the critics are just stuck in 2010 or earlier.
I did not have primarily nuclear in mind, but obstacles to extending long-distance electric grid to support renewables. But hydrogen pipelines are going to have even worse problem with this. And you did not really debunk any of my "stuck in 2010" criticism.
> In reality, we're nearly at the point where hydrogen is a solved problem, but batteries will be a very long ways away from being a car for everyone
I can buy a battery powered vehicle today. Seriously it's 5pm on a Sunday. However the dealer is open till 7pm and they have a couple of dozen Chevy Bolts on the lot.
That's much lower than hydrogen. So what was the argument here?
You can buy a fuel cell car today too. I've notice that many of you guys are stuck in 2010 or so. Fuel cells cars are far beyond your outdated viewpoints.
This is such a bland take these days. Basically every EV owner says the exact same thing. Do any EV owners ever ask themselves "What if I were wrong?" Or better yet, ask themselves "What is the scenario where I am wrong?" The answers to those questions will be much more interesting.
We have petawatt-hours worth of storage capacity.