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Last year I read the following post regarding the application of hydrogen on ground transportation, simple and insightful. It basically explains why it doesn't

Last year I read the following post regarding the application of hydrogen on ground transportation, simple and insightful. It basically explains why it doesn't make sense to use it for that particular application. https://ethz.ch/en/news-and-events/eth-news/news/2021/11/hydrogen-for-ground-transportation-and-heating-is-a-bad-idea.html https://ethz.ch/en/news-and-events/eth-news/news/2021/11/hyd...

rapsey 4y ago
What this article does not address is however the solar problem of producing too much in the summer and too little in the winter. Using the solar energy from summer to produce hydrogen to use in the winter or at night sounds like a complete solution to me. Maybe not for cars or heating, but for powering the grid.
- whatwherewhy 4y ago
  Where's the difference that makes it feasible for powering the grid, but not for powering vehicles?
  - JumpCrisscross 4y ago
    > Where's the difference that makes it feasible for powering the grid, but not for powering vehicles? Energy density. For the fuel alone, volumetrically. Altogether, massively as well.
    - whatwherewhy 4y ago
      Isn't H2 energy density much better than Li-Ion batteries? I don't understand why it's not applicable to transport if so.
      - JumpCrisscross 4y ago
        > Isn't H2 energy density much better than Li-Ion batteries? By weight, hydrogen and oxygen creates 20x more chemical energy per kilogram than lithium-ion batteries [1]. (It's comparable to gasoline and air.) By volume, uncompressed, it has far less. Once compressed, we have to take into account the weight of the containment tanks, the weight of the fuel cell and the energy lost in converting hydrogen to electricity, an output batteries directly provide, a combination which negates that specific energy advantage. [1] https://en.wikipedia.org/wiki/Energy_density_Extended_Reference_Table https://en.wikipedia.org/wiki/Energy_density_Extended_Refere...
      - rgmerk 4y ago
        H2 energy density is better than Li-Ion batteries, particularly by weight, but: * Hydrogen is very light but takes up quite a lot of volume so it needs to be either liquified or compressed to very high pressures (and even then it's considerably bulkier than, say, natural gas). * The resulting storage tanks are heavy and add bulk. * The fuel cell to convert the hydrogen to electricity adds weight that a battery system doesn't have (the storage is the converter). * The energy density of lithium-ion batteries doesn't have to match hydrogen or gasoline, it just has to be good enough. For most light vehicle applications, we're getting pretty close to that point (though possibly not if you're planning to use a truck to tow things). For heavy transport, the balance changes because big tanks are more mass-efficient than smaller ones, and the sheer mass of batteries currently required for long-haul trucking seriously cuts into the cargo that can be legally carried with road mass limits. That's why there's interest in hydrogen-fuelled trucks. For hydrogen-fuelled planes, a similar argument applies with current and reasonably foreseeable battery technology you can't build an airliner with a useful carrying capacity and range. However, the bulk of hydrogen tanks required for a plane with intercontinental range is still a big problem. That's why you see all these unconventional body design concepts for hydrogen-fuelled planes - you need lots of room to store the hydrogen and still give a useful passenger load.
  - rapsey 4y ago
    Cars require a large infrastructure to be in place. EVs use the power grid. Much faster and cost efficient to build large Solar+hydrogen power plants and drive EVs.
  - danielheath 4y ago
    To power vehicles, you would need fuel stations all around the country with hydrogen-fuel equipment. To power the grid from excess solar, you need a hydrogen-burning generator at the site of the electrolysis plant.
    - bamboozled 4y ago
      To power vehicles, you would need fuel stations all around the country with hydrogen-fuel equipment. Why does this keep coming up? Who cares about this specific point? If there is demand, people will build the fuel stations, like we did with gas and oil? I get there are other harder problems with Hydrogen, but worrying about infrastructure seems strange?
      - AtlasBarfed 4y ago
        To summarize, IF you get the practical engineering resolved, IF you get all the consumer products designed and ready for manufacturing, and IF you get a de minimis infrastructure to scale from, that's ... 15 years? Hydrogen infrastructure, if what we're talking about is on the scale of current ICE cars, can't "organically" compete, and won't "organically" develop. It has no chance without a massive government investment/buy-in on a decade long scale. It needs huge investment for each of the big IFs I outlined above. Look at the cost curves of solar / wind / batteries for the last 10 years, and consider that there are numerous technologies about to be rolled out that will improve those at the same or better rate and the overall industrial scaleout / economies of scale isn't close to being done. Hydrogen is marketed these days with "hey it will cost X and that is (theoretically / lies damn lies and accounting) competitive with wind/solar/batteries (which exist and we KNOW what they cost) price today. But there is absolutely no chance of hydrogen being cost competitive in general power transmission/carrier, transportation, etc in 10-15 years. Heck in 5 years it likely won't. So the hydrogen people are praying that their lobbying + fortune would produce some boondoggle subsidy to build this out, and then the government would limp it along due to the sunk cost fallacy.
- Cthulhu_ 4y ago
  I don't mind if it's used to siphon off energy; basically make it a chemical battery that is easily stored, relatively. But I'd rather it be sipohoned off into more immediately usable and scalable storage, e.g. by pumping water up into reservoirs. And batteries, close to where it's being produced, but those are costly.
- ajross 4y ago
  That's "hydrogen as storage", and as such it sits on the efficiency curve quite a bit below batteries and pumped hydro. It's something worth building out if we can find a way to make it work on a balance sheet, but right now we have cheaper ways to solve that problem. Also, recognize that lots of grid load is more flexible than you think. Running smelters and foundries preferentially in the summer is a very doable thing.
  - rapsey 4y ago
    Efficiency is not the only factor. There is also cost and availability. You can't build pumped hydro just anywhere. I have no idea what the cost is compared to lithium batteries though.
    - tonmoy 4y ago
      Also the cost of lithium may rise as more vehicles start using Li-ion batteries, but price of hydrogen storage will likely remain the same
      - bryanlarsen 4y ago
        That's contrary to conventional economics -- costs fall as production increases.
        sacred_numbers 4y ago
        I think the reason hydrogen storage costs won't fall much is because the cheapest technology (metal tanks) have already benefited from economies of scale. The parts that make them suitable for hydrogen storage specifically will get cheaper, but it's unlikely that there's a lot of low hanging fruit for manufacturing the tanks themselves. There could be a breakthrough in metal hydride storage or cryogenic storage that could reduce costs, but I'm not too optimistic. I think the most likely scenario is that most electrolyzed hydrogen is converted to methane for storage and use. Methane is much easier to convert to liquid and much more energy dense, which helps with storage costs.
- Retric 4y ago
  The energy efficiency is so unbelievably terrible it’s a very poor option for balancing the grid even if it wasn’t also more expensive than batteries. People talk about hydrogen for transportation because you can refuel quickly, using expensive fuels is already the norm, and it’s much lighter than batteries. But, it’s so expensive, inefficient, and difficult to store that there needs to be vast technical progresses before it’s viable. Hydrogen would be fairly viable if it was 1/4 as expensive, fuel cells cost 1/4th as much, and the energy density was 4x as high by volume. At which point we could start scaling producing, but batteries are viable today and we are already scaling production.
  - jansan 4y ago
    For large projects Hydrogren will probably be attached to nitrogen to produce ammonium. Technology to handle ammonum has been availble for about 100 years now, and while it has its drawbacks (it is toxic), using ammomium solves a lot of issues.
  - rapsey 4y ago
    70%-80% electrolysis efficiency is unbelievably terrible? There are many factors such as cost, time to market and availability. Batteries require lots of mining of materials and have a limited lifespan.
    - sauwan 4y ago
      Electrolysis only half of the round trip.
    - scythe 4y ago
      Fuel cell efficiency is worse than electrolysis efficiency, about 50%. Even the worst batteries beat that.
      - rapsey 4y ago
        How about cost and availability.
      - 4y ago
- legulere 4y ago
  The solution to the PV problem is wind power. Wind generally blows more during the night and winter. That’s much cheaper and more efficient than generating and storing hydrogen and then turning it into electricity again.
  - ballooney 4y ago
    No it isn't the solution. https://en.wikipedia.org/wiki/Dunkelflaute https://en.wikipedia.org/wiki/Dunkelflaute You need something else for those hours/days/week(s).
raxxorraxor 4y ago
This isn't a good argument to be honest. Sure, it won't save the climate, this is a problem of energy generation. We will always need more than yesterday so we need to look at how we can generate it. The main disadvantage of hydrogen is that it is very difficult to store. It is the smallest element and simply diffuses through almost everything. The efficiencies of energy conversion of hydrogen are quite good for that matter. But BEV (how the author calls them) have major disadvantages as well. Infrastructure needs are unfulfilled, the recycling is maintenance intensive, ... It is still more environmental friendly to drive that 10 year old used tincan than to buy a new electric car. Advantage here is that you don't have local polution, much cleaner city air etc. But neither hydrogen cars nor BEV will save the climate.
- bluGill 4y ago
  > Infrastructure needs are unfulfilled But infrastructure is currently being built out for that. There are very few places in the US (lower 48) that you can't drive a BEV to and back. For some of the remote ones you will need to plan your route around chargers, but you can get just about anywhere. For more dense areas you can just wait until your battery is getting low to start looking. It isn't like gas where you can wait until you are "running on fumes" before starting to look for a charger, but it isn't a big deal. Hydrogen is far behind - maybe it will be built, maybe it won't, I won't predict the future. What I can tell you is if you buy a hydrogen car today you will have to buy the place to fill it at the same time, and you have to assume you will never go out of range.
  - raxxorraxor 4y ago
    Hydrogen also has a lot of problems that make it expensive for car use. But the real problem electric cars have to beat is battery and resource life cycle. You can charge your car now but think about how it would look like if even 30-40% of people would need to charge at the same places. Problem is there is very little incentive for anyone to invest in energy infrastructure. That is a problem affecting EVs, but also a problem that needs to be solved anyway.
- tinco 4y ago

rapsey 4y ago

What this article does not address is however the solar problem of producing too much in the summer and too little in the winter. Using the solar energy from summer to produce hydrogen to use in the winter or at night sounds like a complete solution to me. Maybe not for cars or heating, but for powering the grid.

whatwherewhy 4y ago
Where's the difference that makes it feasible for powering the grid, but not for powering vehicles?
- JumpCrisscross 4y ago
  > Where's the difference that makes it feasible for powering the grid, but not for powering vehicles? Energy density. For the fuel alone, volumetrically. Altogether, massively as well.
  - whatwherewhy 4y ago
    Isn't H2 energy density much better than Li-Ion batteries? I don't understand why it's not applicable to transport if so.
    - JumpCrisscross 4y ago
      > Isn't H2 energy density much better than Li-Ion batteries? By weight, hydrogen and oxygen creates 20x more chemical energy per kilogram than lithium-ion batteries [1]. (It's comparable to gasoline and air.) By volume, uncompressed, it has far less. Once compressed, we have to take into account the weight of the containment tanks, the weight of the fuel cell and the energy lost in converting hydrogen to electricity, an output batteries directly provide, a combination which negates that specific energy advantage. [1] https://en.wikipedia.org/wiki/Energy_density_Extended_Reference_Table https://en.wikipedia.org/wiki/Energy_density_Extended_Refere...
    - rgmerk 4y ago
      H2 energy density is better than Li-Ion batteries, particularly by weight, but: * Hydrogen is very light but takes up quite a lot of volume so it needs to be either liquified or compressed to very high pressures (and even then it's considerably bulkier than, say, natural gas). * The resulting storage tanks are heavy and add bulk. * The fuel cell to convert the hydrogen to electricity adds weight that a battery system doesn't have (the storage is the converter). * The energy density of lithium-ion batteries doesn't have to match hydrogen or gasoline, it just has to be good enough. For most light vehicle applications, we're getting pretty close to that point (though possibly not if you're planning to use a truck to tow things). For heavy transport, the balance changes because big tanks are more mass-efficient than smaller ones, and the sheer mass of batteries currently required for long-haul trucking seriously cuts into the cargo that can be legally carried with road mass limits. That's why there's interest in hydrogen-fuelled trucks. For hydrogen-fuelled planes, a similar argument applies with current and reasonably foreseeable battery technology you can't build an airliner with a useful carrying capacity and range. However, the bulk of hydrogen tanks required for a plane with intercontinental range is still a big problem. That's why you see all these unconventional body design concepts for hydrogen-fuelled planes - you need lots of room to store the hydrogen and still give a useful passenger load.
- rapsey 4y ago
  Cars require a large infrastructure to be in place. EVs use the power grid. Much faster and cost efficient to build large Solar+hydrogen power plants and drive EVs.
- danielheath 4y ago
  To power vehicles, you would need fuel stations all around the country with hydrogen-fuel equipment. To power the grid from excess solar, you need a hydrogen-burning generator at the site of the electrolysis plant.
  - bamboozled 4y ago
    To power vehicles, you would need fuel stations all around the country with hydrogen-fuel equipment. Why does this keep coming up? Who cares about this specific point? If there is demand, people will build the fuel stations, like we did with gas and oil? I get there are other harder problems with Hydrogen, but worrying about infrastructure seems strange?
    - AtlasBarfed 4y ago
      To summarize, IF you get the practical engineering resolved, IF you get all the consumer products designed and ready for manufacturing, and IF you get a de minimis infrastructure to scale from, that's ... 15 years? Hydrogen infrastructure, if what we're talking about is on the scale of current ICE cars, can't "organically" compete, and won't "organically" develop. It has no chance without a massive government investment/buy-in on a decade long scale. It needs huge investment for each of the big IFs I outlined above. Look at the cost curves of solar / wind / batteries for the last 10 years, and consider that there are numerous technologies about to be rolled out that will improve those at the same or better rate and the overall industrial scaleout / economies of scale isn't close to being done. Hydrogen is marketed these days with "hey it will cost X and that is (theoretically / lies damn lies and accounting) competitive with wind/solar/batteries (which exist and we KNOW what they cost) price today. But there is absolutely no chance of hydrogen being cost competitive in general power transmission/carrier, transportation, etc in 10-15 years. Heck in 5 years it likely won't. So the hydrogen people are praying that their lobbying + fortune would produce some boondoggle subsidy to build this out, and then the government would limp it along due to the sunk cost fallacy.
Cthulhu_ 4y ago
I don't mind if it's used to siphon off energy; basically make it a chemical battery that is easily stored, relatively. But I'd rather it be sipohoned off into more immediately usable and scalable storage, e.g. by pumping water up into reservoirs. And batteries, close to where it's being produced, but those are costly.
ajross 4y ago
That's "hydrogen as storage", and as such it sits on the efficiency curve quite a bit below batteries and pumped hydro. It's something worth building out if we can find a way to make it work on a balance sheet, but right now we have cheaper ways to solve that problem. Also, recognize that lots of grid load is more flexible than you think. Running smelters and foundries preferentially in the summer is a very doable thing.
- rapsey 4y ago
  Efficiency is not the only factor. There is also cost and availability. You can't build pumped hydro just anywhere. I have no idea what the cost is compared to lithium batteries though.
  - tonmoy 4y ago
    Also the cost of lithium may rise as more vehicles start using Li-ion batteries, but price of hydrogen storage will likely remain the same
    - bryanlarsen 4y ago
      That's contrary to conventional economics -- costs fall as production increases.
      - sacred_numbers 4y ago
        I think the reason hydrogen storage costs won't fall much is because the cheapest technology (metal tanks) have already benefited from economies of scale. The parts that make them suitable for hydrogen storage specifically will get cheaper, but it's unlikely that there's a lot of low hanging fruit for manufacturing the tanks themselves. There could be a breakthrough in metal hydride storage or cryogenic storage that could reduce costs, but I'm not too optimistic. I think the most likely scenario is that most electrolyzed hydrogen is converted to methane for storage and use. Methane is much easier to convert to liquid and much more energy dense, which helps with storage costs.
Retric 4y ago
The energy efficiency is so unbelievably terrible it’s a very poor option for balancing the grid even if it wasn’t also more expensive than batteries. People talk about hydrogen for transportation because you can refuel quickly, using expensive fuels is already the norm, and it’s much lighter than batteries. But, it’s so expensive, inefficient, and difficult to store that there needs to be vast technical progresses before it’s viable. Hydrogen would be fairly viable if it was 1/4 as expensive, fuel cells cost 1/4th as much, and the energy density was 4x as high by volume. At which point we could start scaling producing, but batteries are viable today and we are already scaling production.
- jansan 4y ago
  For large projects Hydrogren will probably be attached to nitrogen to produce ammonium. Technology to handle ammonum has been availble for about 100 years now, and while it has its drawbacks (it is toxic), using ammomium solves a lot of issues.
- rapsey 4y ago
  70%-80% electrolysis efficiency is unbelievably terrible? There are many factors such as cost, time to market and availability. Batteries require lots of mining of materials and have a limited lifespan.
  - sauwan 4y ago
    Electrolysis only half of the round trip.
  - scythe 4y ago
    Fuel cell efficiency is worse than electrolysis efficiency, about 50%. Even the worst batteries beat that.
    - rapsey 4y ago
      How about cost and availability.
    - 4y ago
legulere 4y ago
The solution to the PV problem is wind power. Wind generally blows more during the night and winter. That’s much cheaper and more efficient than generating and storing hydrogen and then turning it into electricity again.
- ballooney 4y ago
  No it isn't the solution. https://en.wikipedia.org/wiki/Dunkelflaute https://en.wikipedia.org/wiki/Dunkelflaute You need something else for those hours/days/week(s).

raxxorraxor 4y ago

This isn't a good argument to be honest. Sure, it won't save the climate, this is a problem of energy generation. We will always need more than yesterday so we need to look at how we can generate it. The main disadvantage of hydrogen is that it is very difficult to store. It is the smallest element and simply diffuses through almost everything. The efficiencies of energy conversion of hydrogen are quite good for that matter. But BEV (how the author calls them) have major disadvantages as well. Infrastructure needs are unfulfilled, the recycling is maintenance intensive, ... It is still more environmental friendly to drive that 10 year old used tincan than to buy a new electric car. Advantage here is that you don't have local polution, much cleaner city air etc. But neither hydrogen cars nor BEV will save the climate.

bluGill 4y ago
> Infrastructure needs are unfulfilled But infrastructure is currently being built out for that. There are very few places in the US (lower 48) that you can't drive a BEV to and back. For some of the remote ones you will need to plan your route around chargers, but you can get just about anywhere. For more dense areas you can just wait until your battery is getting low to start looking. It isn't like gas where you can wait until you are "running on fumes" before starting to look for a charger, but it isn't a big deal. Hydrogen is far behind - maybe it will be built, maybe it won't, I won't predict the future. What I can tell you is if you buy a hydrogen car today you will have to buy the place to fill it at the same time, and you have to assume you will never go out of range.
- raxxorraxor 4y ago
  Hydrogen also has a lot of problems that make it expensive for car use. But the real problem electric cars have to beat is battery and resource life cycle. You can charge your car now but think about how it would look like if even 30-40% of people would need to charge at the same places. Problem is there is very little incentive for anyone to invest in energy infrastructure. That is a problem affecting EVs, but also a problem that needs to be solved anyway.
tinco 4y ago