this post was submitted on 10 Sep 2026
246 points (97.7% liked)
Green Energy
4591 readers
48 users here now
Everything about energy production and storage.
Related communities:
founded 4 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
doesn't hydrogen have way worse round-trip efficiency than batteries, even before things like embrittlement? i've heard as low as 45%, with the rest just becoming heat.
Yes but how will the oil companies take their unnecessary cut if you use batteries?
why do you think lego is so expensive now
Because it has strong marketing and a cult-like fan base.
Not quite. I mean, partially that is the case, but the good Chinese competition costs on many sets at least 50% of Lego if not more, so the extra margin is there but not astronomically high. Turns out, Lego is one of the most challenging toys to produce (hence it took China so long to catch up in quality, even though they have fully caught up by now), it needs ridiculously high injection molding precision and each product consists of hundreds if not thousand individual parts that need to be correctly sorted.
oil money
Yes, but it can be stored where batteries lose power over time. And a lot of the infrastructure doesn't need to be build but can be converted from natural gas use.
In the end batteries and hydrogen fill two very different gaps. You can use batteries to shift the renewable production peak at noon (thanks solar) to the demand peak in the evening, maybe even flatten fluctuation (in production and demand) over a few days. But they are entirely useless as seasonal long-term storage.
Also plans to produce green hydrogen exist independently. It's a requirement to decarbonise a lot of industry processes where direct use of electricity doesn't work. It's also a raw material in chemical industry.
So if decarbonisation of more than just electricity production is the goal, large scale hydrogen production is a given. As is large scale storage as production from renewable energy will always have seasonal fluctuations. From there having it also double as long-term on-demand stored energy means just scaling up what is already there.
i don't remember if you and i spoke about this before but i did talk to someone on here about the fact that hydrogen can't really be stored for long periods either. whoever it was linked a statement from a german gas company claiming that their existing infrastructure could handle hydrogen without modification, and i remember coming away from that entirely unconvinced.
i'd be happy to be proved wrong but i don't believe green hydrogen is going to play a big part of the grid. i'm personally hoping for pumped hydro and thermal storage.
Sounds indeed like bullshit. More so as here in Germany there are indeed a lot of projects using natural gas infrastructure for the planned hydrogen transport network. But definitely not without modifications.
Europe seems to disagree, with projects worth more than ten times of those in North America and Asia combined.
Edit:
Here's the already approved part of Germany's planned hydrogen core network (new lines, converted lines, opened by 2025):
And an article about one of the earliest segments of 55km opened 1½ years ago, based on 95% pre-existing lines.
And an article (but only available in German) claiming that the planned capacity for 2025 (converted or newly build) is met with new ~525km out of ~9000km by 2032. Of which ~60% will be converted pipelines, 40% new construction.
huh, i thought only japan was betting on hydrogen. i hadn't heard of expansion here. although that's more likely because everything we get about germany is how it's their fault that our electric bill has gone up.
Fun fact: the other big investor in hydrogen pipeline projects is your neighbour to the east... planned to go all the way through the Baltic Sea to Germany.
Also the French energy concept (see: RTE's (French grid provider) study about energy by 2050) is at its core entirely based on nuclear base load in a renewable/storage system making electrolysis more economical because on top of producing hydrogen with excess renewable power during the day, you then also have a steady production of excess electricity throughout low demand night times.
i still find it strange to build out a technology with such a low efficiency. but with CHP plants it could probably be more economical.
Thing about hydrogen efficiency is that we use the wrong reference.
It's not that hydrogen is that inefficient. Big parts of the losses happen when burning it to produce electricity, exactly as with oil, gas or coal. It only is low efficiency when compared to batteries filled with green electricity from solar, wind an hydro (the only production methods that are not a rather primitve "boil water and run a turbine").
Batteries and electrification in general are just so much better.
But if your requirement is burning gas for process heat in industries where electrification doesn't work and as peaking power plants to meet demand spikes the alternative would be natural gas (or sometimes coal) with also huge losses from production to transport to getting burned for heat.
for peaker plants i've always assumed we'd do fuel cells. just plumbing it in to existing gas infra (aka just fucking boiling water again) seems like it doesn't really solve the problem.
but yeah for applications that require heat rather than electricity it's a good idea. i think having generators on site is probably the more likely solution there.
Ammonia is used for fertiliser and could be used as fuel. About 1/3rd the energy density of petrol and much easier to store than hydrogen.
Probably wouldn't want to plan to run the grid extensively on it. But if you are just having it to cover rare occasions then it could work well.
Also gotta make a shitload of it for fertiliser production anyway. Cheap excess wind/solar power could make it economically practical.
But at that point why have hydrogen-based or ammonia-based energy infrastructure? Why not use the excess electricity to make fertilizer and use that to grow crops?
Are the factories that make hydrogen so much cheaper than the factories that make fertilizer that when you build enough factories to make use of all the excess electricity (meaning they're idle 80% of the time), the cost of having those factories make fertilizer instead of hydrogen is greater than the cost of building and maintaining the entire infrastructure for using hydrogen or ammonia as energy storage/fuel?
Its not fertiliser instead of hydrogen, hydrogen is a required ingredient for the haber-bosch process. Currently we get the hydrogen from fossil fuels because it is cheaper.
In reality that does not happen on its own. Once you figure in the use of land, water and energy to grow crops it's the by far most inefficient way.
Even without the additional costs in farming and just assuming all those plants happily grow on their own, plants are still losing... "Photosynthesis turns roughly 3 percent of incoming sunlight into organic compounds [...] "Artificial photosynthesis"—comprising a PV cell that provides the electricity to split water into hydrogen and oxygen—turns roughly 10 percent of incoming sunlight into usable hydrogen[...]"
isn't methanol better for fuel?
Is that as efficient to produce from excess energy? Especially energy that might be highly variable. Hydrogen production can be turned on/off instantaneously and only need a fairly small amount of buffer space for it if you are turning it into something else.
no, it requires a lot of heat. but on the other hand it binds hydrogen into a more stable form and can be made with captured carbon.
Ammonia requires hydrogen and nitrogen from the air. Both certainly are more stable than hydrogen on its own.
yeah ammonia is also a good idea. a lot harder to handle safely though, it tends to corrode things.
Hydrogen is the smallest atom and literally cannot be contained by any other material in the universe over time. Not to mention the intense refrigeration and pressure requirements.
@anon6854@lemmy.world which part of what I said is factually incorrect?
That's why it will never IMO be feasible until we have surplus electric power that it can be made with. Power that would otherwise be wasted.
Hydrogen has other uses too. Currently we use gas which results in carbon emissions. But with cheap enough energy, you can get hydrogen from water. There is also an option to not emit the carbon when using gas, but you get less hydrogen for the same input so no one is going to do that at scale.
Another major use for hydrogen is the haber-bosch process.
most hydrogen is produced from natural gas unfortunately :(
It is currently. But cheap renewable energy makes renewable hydrogen a more viable option.
it's currently about 5x the cost to produce so i think some other incentives are probably needed as well...
Currently, but a large part of that cost is due to energy prices. If you have cheaper energy, or periods of excess energy that bring the cost down to/near zero, that is what brings down the cost.
if only we actually got there... here the prices have been climbing more and more the more wind turbines we install because of grid instability.
honestly a great pilot area for energy storage.
Variable tariffs are an option here and can give you periods of very cheap, free or even negative cost energy.
Think of negative cost energy as paying someone to dispose of something you don't need, like how trash haulers get paid to take stuff away.
If we get to the point where we have a bunch of generation for peak demand plus storage, and still have excess energy in other times, we can and should investigate fixing that excess energy into stable chemical molecules that are useful for other things (whether it's good for a material, for energy storage, for some other consumable like fertilizer, or even simply reversing carbon emissions by fixing carbon into stable non-CO2 compounds).
here too, but it doesn't really help the people who live in apartments :(
No but I don't expect you to make hydrogen or ammonia in your apartment beyond perhaps some hydrogen chemistry experiments for fun. Ammonia is probably a bit much to do at home.
depends on what i had the night before
Edit: i was thinking more of the flexible tariffs...