Manfredo_1

And you still are pretending that steam power plants running on hydrogen don't exist.

Yet again, you originally said we could use gas turbines for hydrogen storage. Not steam turbines. Of course steam turbines can easily be run off hydrogen, you don't need compressor blades, combustors, or anything special. Just a source of heat, a boiler, and a steam turbine. This is less efficient, so there's good reason to develop hydrogen gas turbines.

You're the one who first brought up steam turbines when you changed the goal posts to saying we could repurpose coal plants instead of gas turbines.

And good night.

I didn't reject future hydrogen gas turbines. In fact, I'm the one who brought them up. That's the entire point I'm making: hydrogen gas turbines are still in development. If hydrogen gas turbines already exist, why are GE, Siemens, and others talking about how they plan to develop hydrogen gas turbines by 2030 or 2040? They're not off the shelf technology, because they aren't even on the shelf yet.

Im going to bed now, and I should have realized I was being trolled much sooner.

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.

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.

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.

So your own source disagrees with you.

Did you miss the "in 2030" part?

Most companies are targeting hydrogen gas turbines to be produced in 2030 or 2040: https://www.siemens-energy.com/global/en/news/magazine/2019/...

They aren't "off the shelf" technology yet.

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?

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).

nevermind this whole goalpost moving argument of "current gas turbine already in existence."

This was the original goalpost. Let's re-read it: https://news.ycombinator.com/item?id=26599162

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].

1. https://news.ycombinator.com/item?id=26599959

If we aren't using combined cycle gas turbines round-trip efficiency of hydrogen storage is seriously reduced.

I'm not moving any goalpost. This is your comment when you claimed that gas turbines could be repurposed to burn hydrogen: https://news.ycombinator.com/item?id=26599162

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.

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?

Right. Lithium batteries won't cut it. That leaves geographically-dependent hydroelectricity, which isn't so easy to build. And then proposed solutions that are still in the prototyping phase, and aren't commercially available.

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.

For the third time, storage is only one part of the puzzle. We also need a way to cheaply electrolyze water into hydrogen, compress it into the storage facility, and then use it to generate electricity. Nobody doubts that you can pump hydrogen into a big cave. What's dubious is transforming this into a usable energy-storage facility.

We haven't done this to provide 100 MWh of storage. How on earth can we be confident it'll be easy to provide 1 TWh of storage, or 10 TWh?

People mostly talk about lithium ion storage because that's what's actually available, besides geographically limited options like hydroelectricity. Until there's a company that's building dozens of gigawatt hours of hydrogen storage it's a moot point. It's a technology that exists the laboratory, not one that's commercially available.

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.

Hydrogen embrittlement is a real thing, don't just go hand-waving it away: https://www.energy.gov/sites/prod/files/2014/03/f12/hpwgw_em...

What about thermodynamics am I missing?

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.

https://www.economist.com/science-and-technology/2020/12/08/...

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

A solar heavy network would still need 12 hours of storage to accommodate nighttime energy use. More actually, because of greater seasonal fluctuations further from the equator.

All of the Americas experience night time simultaneously for at least 8 hours a day. Even if we ran HVDC lines to the Sahara, there's still a period of time where most sunlight is shining on the pacific ocean.

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.

That's a question that can't be answered until people actually build hydrogen storage facilities at scale.

Why shouldn't nuclear plants scale? They're mostly just steel and concrete. Uranium is more than 40 times more prevalent than gold, and it's energy density is such that it represents a negligible cost of operations. The technology is just scaling up existing components, we had nuclear powered submarines for a while. This is what people thought about nuclear power in the 1950s and early 60s. As plants actually started being constructed problems such as corrosion, large amounts of earth moving, metal impurities, and more were discovered and made the plants more expensive.

We haven't discovered these issues with hydrogen storage. We won't discover these issues until we actually build hydrogen storage facilities at scale. We don't know what challenges will lie in store when building hydrogen storage, because we've never done it before. This is why it's useless to talk about the cost of hydrogen storage until we actually have experience building and operating hydrogen storage plants. Our knowledge of cost of hydrogen storage is in the same situation as nuclear power in the 1950s.

So, when you said hydrogen rapidly corrodes any metal it comes into contact with, that didn't include the metal that the chemical industry makes their equipment from? So, let's just put a "this is chemical industry" signs on our hydrogen storage plants, and presto! Magically protected!

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.

And from your link:

The use of hydrogen as a gas turbine fuel has been demonstrated commercially, but there are differences between natural gas and hydrogen that must be taken into account to properly and safely use hydrogen in a gas turbine. In addition to differences in the combustion properties of these fuels, the impact to all gas turbine systems as well as the overall balance of plant, must be considered. In a power plant with one or more hydrogen-fueled turbines, changes may be needed to the fuel accessories, bottoming cycle components, and plant safety systems. GE’s broad field experience enables our engineers to understand the impact of using hydrogen as a gas turbine fuel.

Hmm, maybe not so simple.

And when we look at what's actually being deployed, it's not 100% hydrogen it's a mixture that's mostly natural gas with only a small portion of hydrogen:

https://www.nsenergybusiness.com/features/gas-turbines-hydro...

The new gas turbines will be commercially guaranteed capable of using a mix of 30% hydrogen and 70% natural gas fuel. Between 2025 and 2045, the hydrogen capability will be systematically increased to 100% renewable hydrogen.

These turbines still mostly burn natural gas. GE says it'll get there eventually, possibly over the course of 3 decades.

We'd actually need 3 weeks of storage to migrate to a fully renewable grid: https://pv-magazine-usa.com/2018/03/01/12-hours-energy-stora...

Then our transition to solar + wind needs to include the cost of installing a septic tank and water reservoir in every household. And a thermal battery for heating. And an electric battery for lighting. And all the other things we'll need to do to accommodate an unreliable energy grid.

Storing hydrogen is only one piece of the puzzle. Yes, if you happen to live near an abandoned salt mine that's a convenient place to put a large quantity of hydrogen. That doesn't solve the problem of massive electrolysis facilities, and turbines that can burn hydrogen.

And it certainly doesn't answer the question of whether or not this represents a viable grid-storage solution, since we haven't built it at remotely close to the scale required.

It's not "if it isn't already being done, it can't be done"

It's "if it isn't already being done, it is extremely reckless to assume that it can be done cheaply at a massive scale".

Screw it, let's just use fusion. Nobody has actually built a fusion plant? Well, who cares if it hasn't already been done, that's a "foolish argument" in your own words. /s

You're falling back to the "if it works on paper it'll be guaranteed to work at scale, and work cheaply" argument. Please stop this foolishness.

It's not just a question of storage, you can just use a salt cavern for that.

It's also a question of electrolyzing water into hydrogen efficiently.

And converting it back into electricity efficently.

And building all of these systems cheaply.

And deploying all of these systems at massive scale.

We're still on the first phase of that. As per your other comment we still don't even have effective elctrolysers to do this cost-effectively [1].

Will hydrogen storage pan out? Maybe. But until then it's not a solution. It's a potential solution, like fusion, or algae in vats, and thermal storage, and all the other potential solutions being proposed. It's not a solution that has actually demonstrated viability.

!. https://news.ycombinator.com/item?id=26599346

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.

Unfortunately, those alloys that experience embrittlement includes the ones used in steam turbines: https://www.sciencedirect.com/science/article/abs/pii/S09215...

That "manipulation of hydrogen" mostly involves use in the the chemical industry. We don't use hydrogen to power gas turbines.

I'm not sure why you're trying to deny the existence of chemical facts: https://www.twi-global.com/technical-knowledge/faqs/what-is-....

Name one hydrogen electric grid storage facility. Not prototypes, but actual commercial facilities connected to the grid.

You insist that hydrogen is so technically ready, yet nobody is using it.

No, hydrogen rapidly corrodes any metals that it comes into contact with. If they are interchangeable, expect drastically smaller service intervals.

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.

Yes, those incentives exist to try and shape demand. But in practice, people rarely take advantage of them. And some things really can't be shaped. The pumps that deliver your water cannot have their demand shaped, unless you're willing to go without running water for some hours of the day.