4 ms·

Very enlightening writeup - thanks for being thorough. I'd like to mention that Toyota is playing with syntetic fuels as well, and that some in the car market

by dmbche 3y ago

Very enlightening writeup - thanks for being thorough. I'd like to mention that Toyota is playing with syntetic fuels as well, and that some in the car market see this more as an option for car enthusiasts to keep running their cars when gas will be "obsolete". Much of the marketing of the corolla is about how "the engine is not not-green, it's the fuel that's the issue". Seeing how gas powered engines are much less efficient (just from the heat waste) than electric ones, I have a hard time expecting hydrogen to become a normal fuel for cars - especially with the risks associated. Can you imagine a transparent flame in your car? This seems more like rnd into syntetic fuels and alternatives for enthusiasts than their actual horse in the race.

_hypx 3y ago
Fuel cells are not combustion engines. They are electrochemical systems. Their theoretical efficiency is the same as li-ion batteries. And this is why it is a 100% guarantee that they will displace li-ion batteries. Why on Earth would anyone choose a very expensive and unsustainable battery technology when there is another system that is just as good but does not have any of those weaknesses? It's pure BEV brainwashing that people even think that way. So my advice to you is stop believing in these lies and accept that cars of the future will be hydrogen powered.
- _aavaa_ 3y ago
  This is highly misleading. The theoretical efficiency for a fuel cell car and a battery electric car are absolutely not the same when you look at well-to-wheel. Not even close. As for unsustainable. People make a big deal about cobalt in the batteries. Fine, the cobalt is being removed, all that’s left is abundant minerals. Can you say the same about the platinum-group metals in electrolyzers and fuel cells?
  - _hypx 3y ago
    But the fact that they are the same should mean something to you. It also helps not to spam FUD about efficiency, and in the real-world they are much closer than you are thinking. In fact, hydrogen cars are the second most efficient form of transportation possible, and far less resource dependent than batteries. You do not need platinum in a fuel cell. There are several types of them, and only one of them require platinum. Also, the amount required is comparable to a catalytic converter and only grams per fuel cell is needed: https://www.reuters.com/article/us-platinum-week-bosch-fuelcells-exclusi/exclusive-bosch-goes-for-platinum-light-fuel-cells-idUSKCN1SJ0FG https://www.reuters.com/article/us-platinum-week-bosch-fuelc...
    - _aavaa_ 3y ago
      > But the fact that they are the same should mean something to you. Yeah, it means i'd love a refence, and one that includes actual effiency too. > It also helps not to spam FUD about efficiency, and in the real-world they are much closer than you are thinking. BEV well to wheel is 77% while hydrogen is 33% [0]. A 2x is what I have in mind. > In fact, hydrogen cars are the second most efficient form of transportation possible Yes, a far far second behind electric and far far ahead petrol, which is not particularly hard to do. [0]: https://www.transportenvironment.org/wp-content/uploads/2020/12/2020_12_Briefing_feasibility_study_renewables_decarbonisation.pdf https://www.transportenvironment.org/wp-content/uploads/2020...
      - _hypx 3y ago
        https://www.sciencedirect.com/science/article/abs/pii/S0360319918308371 https://www.sciencedirect.com/science/article/abs/pii/S03603... The maximum possible efficiency of a fuel cell is 100%. It follows directly from the realization that they are not limited by Carnot's cycle. Hence why in the long run, it is pretty much a guarantee that a hydrogen based solution will win out. If two solutions are equally efficiency, than the only that is vastly cheaper will be the solution. These types of comparisons of efficiency comparisons are ultimately just nonsense. Most of them are all over the place, from 2x difference to sometimes 10x or worse. That's because they are just cherry-pick numbers in order to create a narrative. It is not really based on any sort of real analysis. In reality, a large portion of renewable energy is lost or never utilized, largely due to its intermittency. Without any way of storing it, renewable energy is very inefficient overall. They pretty much always have to be backed up by fossil fuels today. Adding a way to store vast amounts of it, such as hydrogen, makes renewable energy significantly more efficient and eliminates the need for fossil fuels. But if you make that realization, then it also becomes obvious that running cars off of hydrogen does not imply any kind of major loss of efficiency. The problem basically becomes irrelevant, since you are running cars off of energy that would've been lost anyways.
_aavaa_ 3y ago
Toyota has also pitched actually burning the hydrogen, but that’s even stupider. For starters you still get NOx formation by burning it, plus your efficiency is even lower. The problem with synthetic fuels isn’t the technology, it’s the economics. Synthetic fuels, to be remeotely green, need hydrogen created from electrolyzing water. That need to be done with 100% green energy (and new green energy, not simply pull from the grid to cause fossil fuel plants in o come online). Then you need carbon from someone here other than fossil fuels. Direct air capture is what many look at, and that’s very expensive because of the chemistry and thermodynamics. (You’re trying to pull co2 out of the air, something in concentrations in the parts per million). At the end of this Rube Goldberg operation you’re left with a fuel that’s going to cost 10x the price. And the only way the price goes down is if people buy a lot of it so that the technology can improve and so the plants increase to get economies of scale. Porsche is building a plant for this. But idk about you, but I doubt there are enough people who care enough about their car, and could afford, to pay >40$/gallon for gasoline.

by dmbche 3y ago

_hypx 3y ago

Fuel cells are not combustion engines. They are electrochemical systems. Their theoretical efficiency is the same as li-ion batteries. And this is why it is a 100% guarantee that they will displace li-ion batteries. Why on Earth would anyone choose a very expensive and unsustainable battery technology when there is another system that is just as good but does not have any of those weaknesses? It's pure BEV brainwashing that people even think that way. So my advice to you is stop believing in these lies and accept that cars of the future will be hydrogen powered.

_aavaa_ 3y ago
This is highly misleading. The theoretical efficiency for a fuel cell car and a battery electric car are absolutely not the same when you look at well-to-wheel. Not even close. As for unsustainable. People make a big deal about cobalt in the batteries. Fine, the cobalt is being removed, all that’s left is abundant minerals. Can you say the same about the platinum-group metals in electrolyzers and fuel cells?
- _hypx 3y ago
  But the fact that they are the same should mean something to you. It also helps not to spam FUD about efficiency, and in the real-world they are much closer than you are thinking. In fact, hydrogen cars are the second most efficient form of transportation possible, and far less resource dependent than batteries. You do not need platinum in a fuel cell. There are several types of them, and only one of them require platinum. Also, the amount required is comparable to a catalytic converter and only grams per fuel cell is needed: https://www.reuters.com/article/us-platinum-week-bosch-fuelcells-exclusi/exclusive-bosch-goes-for-platinum-light-fuel-cells-idUSKCN1SJ0FG https://www.reuters.com/article/us-platinum-week-bosch-fuelc...
  - _aavaa_ 3y ago
    > But the fact that they are the same should mean something to you. Yeah, it means i'd love a refence, and one that includes actual effiency too. > It also helps not to spam FUD about efficiency, and in the real-world they are much closer than you are thinking. BEV well to wheel is 77% while hydrogen is 33% [0]. A 2x is what I have in mind. > In fact, hydrogen cars are the second most efficient form of transportation possible Yes, a far far second behind electric and far far ahead petrol, which is not particularly hard to do. [0]: https://www.transportenvironment.org/wp-content/uploads/2020/12/2020_12_Briefing_feasibility_study_renewables_decarbonisation.pdf https://www.transportenvironment.org/wp-content/uploads/2020...
    - _hypx 3y ago
      https://www.sciencedirect.com/science/article/abs/pii/S0360319918308371 https://www.sciencedirect.com/science/article/abs/pii/S03603... The maximum possible efficiency of a fuel cell is 100%. It follows directly from the realization that they are not limited by Carnot's cycle. Hence why in the long run, it is pretty much a guarantee that a hydrogen based solution will win out. If two solutions are equally efficiency, than the only that is vastly cheaper will be the solution. These types of comparisons of efficiency comparisons are ultimately just nonsense. Most of them are all over the place, from 2x difference to sometimes 10x or worse. That's because they are just cherry-pick numbers in order to create a narrative. It is not really based on any sort of real analysis. In reality, a large portion of renewable energy is lost or never utilized, largely due to its intermittency. Without any way of storing it, renewable energy is very inefficient overall. They pretty much always have to be backed up by fossil fuels today. Adding a way to store vast amounts of it, such as hydrogen, makes renewable energy significantly more efficient and eliminates the need for fossil fuels. But if you make that realization, then it also becomes obvious that running cars off of hydrogen does not imply any kind of major loss of efficiency. The problem basically becomes irrelevant, since you are running cars off of energy that would've been lost anyways.

_aavaa_ 3y ago

Toyota has also pitched actually burning the hydrogen, but that’s even stupider. For starters you still get NOx formation by burning it, plus your efficiency is even lower. The problem with synthetic fuels isn’t the technology, it’s the economics. Synthetic fuels, to be remeotely green, need hydrogen created from electrolyzing water. That need to be done with 100% green energy (and new green energy, not simply pull from the grid to cause fossil fuel plants in o come online). Then you need carbon from someone here other than fossil fuels. Direct air capture is what many look at, and that’s very expensive because of the chemistry and thermodynamics. (You’re trying to pull co2 out of the air, something in concentrations in the parts per million). At the end of this Rube Goldberg operation you’re left with a fuel that’s going to cost 10x the price. And the only way the price goes down is if people buy a lot of it so that the technology can improve and so the plants increase to get economies of scale. Porsche is building a plant for this. But idk about you, but I doubt there are enough people who care enough about their car, and could afford, to pay >40$/gallon for gasoline.