Submitted by Realistic-Plant3957 t3_zz1fxq in Futurology
grundar t1_j2clcsr wrote
Reply to comment by gregorydgraham in Green Hydrogen - Not The Fuel Of The Future by Realistic-Plant3957
> The methane reforming reaction is orders of magnitude more effective at making hydrogen than electrolysis.
That's just not accurate -- industrial electrolysis is around 75% efficient, meaning the amount of energy required to produce hydrogen will be in roughly the same ballpark regardless of whether it's via steam reformation of methane or via renewable-powered electrolysis.
Much of the price difference, then, is driven by natural gas being a cheaper energy source than electricity. There are 293 kWh per mcf, and in the US gas is about $5/mcf, so that's about 1.7c per kwh of energy. That's low, but renewable costs are falling to meet or even beat that -- solar has fallen to 1-2c/kWh in excellent locations, and much US wind is around 2c/kWh.
So the cost of hydrogen from electrolysis is actually not that far off the cost of hydrogen from steam reformation, and it's getting more cost-competitive all the time as scaling up renewables puts downward pressure on their costs.
zenfalc t1_j2cqogl wrote
All true, but I still don't think hydrogen makes the leap. I wouldn't mind if it did, but the use cases won't stack well against some of the upcoming battery technologies. Much cheaper, higher energy density, more rapid charge and discharge ability, and no toxic chemicals...
Don't misunderstand me: I get hydrogen has a lot of benefits. I just don't think it comes to pass.
Taxoro t1_j2cwalq wrote
Batteries can't make green fertilizers or steel.
grundar t1_j2eizy1 wrote
> All true, but I still don't think hydrogen makes the leap. I wouldn't mind if it did, but the use cases won't stack well against some of the upcoming battery technologies.
That's a reasonable assessment, but as others have noted there're use cases that use hydrogen chemically rather than for energy (steel, fertilizer, etc.), so I expect significant hydrogen production for those.
Given that there will be significant hydrogen production, and given that hydrogen can be stored efficiently in the same salt caverns currently used for natural gas, I wouldn't be surprised to see hydrogen have some role in the power grid for seasonal storage.
Hydrogen for transportation is much more questionable; small-scale (cars) seems highly unlikely, but large-scale (container ships) might happen.
bremidon t1_j2cxmr7 wrote
Agreed. About 15 years ago, I was absolutely convinced that hydrogen was the obvious choice and that batteries were a dead-end. Hydrogen only had a few (admittedly big) problems to solve and batteries seemed like they had a never-ending list of challenges to get past.
Fast forward to today and batteries have pretty much solved all their challenges and are now simply going from strength to strength. Meanwhile, hydrogen has barely moved forward from where it was 15 years ago.
My two observations are:
- Hydrogen does not merely need to be better than batteries; it needs to be significantly better than batteries to justify even bothering to develop and roll out. It cannot even keep up with batteries currently, is losing ground, so hoping hydrogen can leapfrog batteries seems unrealistic.
- While I readily accept that life is full of surprises and perhaps we'll get yet another twist in the hydrogen-vs-battery fight, there is no indication that something like that is building up.
FeatheryBallOfFluff t1_j2d5zz0 wrote
There have been more investments and longer development times in battery tech than in hydrogen tech. I believe we should develop both. Who knows what amazing results hydrogen tech can achieve once it's fully developed? Perhaps once hydrogen tech is optimized, it can be synthesized from anywhere (say a boat on sea, or on the moon once water is found) and may provide a higher energy density than any other storage form (solid hydrogen storage is being investigated as it is). Perhaps rockets will make use of new hydrogen tech. Perhaps it can be used to create drinkable water in space, from non-drinkable components.
We should give it a chance before focusing only on batteries, as we would miss out on possible amazing tech by focusing only on batteries.
bremidon t1_j2d9wze wrote
>There have been more investments and longer development times in battery tech than in hydrogen tech.
I would love to have link on this. It's not surprising that battery tech would be getting more investment now; proving a technology works and a market exists does wonders for encouraging investment. But I would be willing to bet that the situation was quite different even 5 or 10 years ago.
So do you have anything for me?
tripodal t1_j2d3gbf wrote
Storing hydrogen is insanely difficult. Doing it at grid scale has to have astronomical costs
grundar t1_j2eiiy9 wrote
> Storing hydrogen is insanely difficult. Doing it at grid scale has to have astronomical costs
Surprisingly, storing hydrogen at grid scale is the only time it's relatively easy to do so.
Hydrogen can be stored in salt caverns, and those are already used extensively for long-term natural gas storage, so the infrastructure for grid-scale hydrogen storage is more-or-less already there (some piping would need to be upgraded).
Small-scale use (like cars) doesn't make economic or logistical sense, but large-scale use (like seasonal electricity storage or green steel manufacturing) is looking fairly reasonable.
tripodal t1_j2fxar0 wrote
I wasn’t aware salt caverns were airtight to hydrogen; but that’s a relatively small piece of the distribution required.
New power plans or water distributing and or electrical distribution will be needed and contributes
netz_pirat t1_j2d2uym wrote
Just as an addon: gas is way way way more expensive in Europe, Spot market prices are about triple of what you listed for the us, even before the war.
So gree hydrogen has already broken even here, and there are several agreements in place to generate green hydrogen in spain, tunesia,... And send it to northern Europe per pipeline.
Eelroots t1_j2d6lr8 wrote
That's where carbon taxes may drive the development in the right direction. We need zero carbon emissions, not a discussion on which color may be fancier or generate more revenues. Zero carbon or nothing.
tripodal t1_j2d3bxx wrote
It will always be cheaper to make hydrogen from methane than electricity; until the entire grid is renewable.
Then it will still be cheaper because some fraction of the energy required can come from the methane.
The efficiency of electrolysis is dependent on the quality of the equipment and water. Fresh water costs more than oil and that will not change anytime soon.
FeatheryBallOfFluff t1_j2d61ay wrote
They can already make hydrogen from seawater
tripodal t1_j2fwvr1 wrote
They can but it’s difficult and requires enormous amounts of consumables as seawater destroys everything it touches.
grundar t1_j2fpeo4 wrote
> Fresh water costs more than oil and that will not change anytime soon.
Even water from the tap is over 100x cheaper than oil.
For example, Los Angeles homes pay ~$10/hcf; 1 hcf = 748gal, so that's about 1.3c per gallon for tapwater.
tripodal t1_j2fxjmn wrote
Whoooops your right
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