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Good points. I’ve always been curious. Why not just plug in A hydrogen car and run the fuel cell in reverse to get a tank of hydrogen?

pmorici 7y ago
The only reason that Hydrogen powered cars are even still discussed over battery electric is that 95% of industrial hydrogen is produced from fossil fuels. In other words the people pushing it are probably protecting their oil and gas interests. They aren't going to put money into research to cut themselves out of the loop. [0] https://en.wikipedia.org/wiki/Hydrogen_production https://en.wikipedia.org/wiki/Hydrogen_production
- Hypx 7y ago
  But nobody is suggesting that industrial hydrogen will be natural gas based forever. Furthermore, we must have green hydrogen for steel and ammonia production. So this is a “must solve” problem no matter what. This is basically the same kind of argument that BEVs are “secretly powered by coal.” These are backwards looking statements that are going to be wrong in the near future.
- clouddrover 7y ago
  > In other words the people pushing it are probably protecting their oil and gas interests. Shell builds EV charging stations: https://www.youtube.com/watch?v=nst2RGtgzfk https://www.youtube.com/watch?v=nst2RGtgzfk BP builds EV charging stations: https://www.youtube.com/watch?v=zaSRn6hYOwc https://www.youtube.com/watch?v=zaSRn6hYOwc Petro-Canada builds EV charging stations: https://www.petro-canada.ca/en/personal/fuel/canadas-electric-highway https://www.petro-canada.ca/en/personal/fuel/canadas-electri... They're in the energy business. They don't really care what form it takes.
  - blibble 7y ago
    in a world where everyone has a charger at home and at work there's little to no need for Shell and BP hence their push for hydrogen, where everything remains essentially the same (and they keep their vertically integrated business)
    - clouddrover 7y ago
      Look, Shell is the third largest company in the world. They have many, many business interests. The idea that more EVs means Shell goes broke is pure fantasy.
      - blibble 7y ago
        what sort of argument is that? large companies disappear all the time, or are swallowed by by others that outcompete them "9 of every 10 Fortune 500 companies in 1955 are gone": https://www.aei.org/carpe-diem/fortune-500-firms-1955-v-2017-only-12-remain-thanks-to-the-creative-destruction-that-fuels-economic-prosperity/ https://www.aei.org/carpe-diem/fortune-500-firms-1955-v-2017...
        clouddrover 7y ago
        > what sort of argument is that? It isn't "an argument". It's simply a practical reality which contradicts your false preconceptions.
        tomhoward 7y ago
        That 9/10 figure is misleading, if you browse the list here: https://money.cnn.com/magazines/fortune/fortune500_archive/full/1955/1.html https://money.cnn.com/magazines/fortune/fortune500_archive/f... Many more than 1/10 of those names are still dominant companies/brands, but some have gone through mergers or restructures, meaning the 1955 entity no longer exists but the business lives on and remains very strong. BP and Shell are on that 1955 list, and are obviously still very strong companies. According to the Lindy effect [1], the longer a company has existed, the longer it is likely to continue to exist. Both BP and Shell have long been diversified companies (even in the 1950s, Shell had vast business activities outside of petroleum), and have long been investing heavily in various forms of alternative energy. They're not likely to disappear in any foreseeable timeframe. [1] https://en.wikipedia.org/wiki/Lindy_effect https://en.wikipedia.org/wiki/Lindy_effect
  - kube-system 7y ago
    It is advantageous to get a foot hold in competitive markets, for sure.... but these actions are also heavily motivated by ulterior motives: tax credits, PR/marketing, lobbying, undermining competitive threats, etc.
    - clouddrover 7y ago
      So just like every big business in every industry.
danans 7y ago
Doing this would defeat the only advantage hydrogen has, which is rapid fueling. To add to the inconvenience, you'll need to plug in both the electricity, and a hose to your supply of distilled water. Beyond that, the best case efficiency for such a hydrogen production process in an industrial setting is 80% (using a process which feeds waste heat back into the electrolysis reaction). From the hydrogen back to energy moving the wheels is at most 50% efficient, so a total plug to wheels efficiency of less than 40%. In the real world, it will be far less efficient than that (probably 25% at best), and very expensive to achieve in a practical car for sale, for the same reason that hydrogen fuel cells in cars are expensive today. That vs the typical plug to wheels efficiency of around 60% in today's electric vehicles. And such regenerative hydrogen fuel cells do not even exist for automotive applications today. This paper has several lifecycle efficiency graphs that explain aspects of this in some detail: https://www.mdpi.com/2032-6653/9/1/3 https://www.mdpi.com/2032-6653/9/1/3
- Hypx 7y ago
  https://www.sciencedirect.com/science/article/abs/pii/S036031991000340X https://www.sciencedirect.com/science/article/abs/pii/S03603... The best case scenario like you described is about 98%. FYI, 80% is already being hit by real world normal electrolysis reactions. It’s very likely we’re in the same position with fuel cell cars that solar was back in the late-2000s. Arguments that it is “too expensive” are really falling apart, especially considering that green hydrogen is around $2-3/kg today, and that platinum loading has dropped to around 10 grams for a car sized fuel cell.
  - danans 7y ago
    > FYI, 80% is already being hit by real world normal electrolysis reactions. Not in a fuel-cell running in reverse in a car, though, which is what the GP was referring to. > especially considering that green hydrogen is around $2-3/kg today More like $3-7 per kg today [1]. And as that article (which is less than 1 month old) points out, producing green hydrogen would require an absolutely massive buildout of renewables, which would better be put to direct use without the conversion penalty to hydrogen. Hydrogen energy storage will still have its niche applications on the margins, but it is unlikely to catch up to the cost and availability advantages of batteries for cars in places where the existing electric grid reaches. 1. https://www.rechargenews.com/transition/a-wake-up-call-on-green-hydrogen-the-amount-of-wind-and-solar-needed-is-immense/2-1-776481 https://www.rechargenews.com/transition/a-wake-up-call-on-gr...
gok 7y ago
One issue is that you need a source of water. Another is that electrolysis is only around 70% efficient, whereas (say) lithium ion battery charging is more like 95% efficient.

pmorici 7y ago

The only reason that Hydrogen powered cars are even still discussed over battery electric is that 95% of industrial hydrogen is produced from fossil fuels. In other words the people pushing it are probably protecting their oil and gas interests. They aren't going to put money into research to cut themselves out of the loop. [0] https://en.wikipedia.org/wiki/Hydrogen_production https://en.wikipedia.org/wiki/Hydrogen_production

Hypx 7y ago
But nobody is suggesting that industrial hydrogen will be natural gas based forever. Furthermore, we must have green hydrogen for steel and ammonia production. So this is a “must solve” problem no matter what. This is basically the same kind of argument that BEVs are “secretly powered by coal.” These are backwards looking statements that are going to be wrong in the near future.
clouddrover 7y ago
> In other words the people pushing it are probably protecting their oil and gas interests. Shell builds EV charging stations: https://www.youtube.com/watch?v=nst2RGtgzfk https://www.youtube.com/watch?v=nst2RGtgzfk BP builds EV charging stations: https://www.youtube.com/watch?v=zaSRn6hYOwc https://www.youtube.com/watch?v=zaSRn6hYOwc Petro-Canada builds EV charging stations: https://www.petro-canada.ca/en/personal/fuel/canadas-electric-highway https://www.petro-canada.ca/en/personal/fuel/canadas-electri... They're in the energy business. They don't really care what form it takes.
- blibble 7y ago
  in a world where everyone has a charger at home and at work there's little to no need for Shell and BP hence their push for hydrogen, where everything remains essentially the same (and they keep their vertically integrated business)
  - clouddrover 7y ago
    Look, Shell is the third largest company in the world. They have many, many business interests. The idea that more EVs means Shell goes broke is pure fantasy.
    - blibble 7y ago
      what sort of argument is that? large companies disappear all the time, or are swallowed by by others that outcompete them "9 of every 10 Fortune 500 companies in 1955 are gone": https://www.aei.org/carpe-diem/fortune-500-firms-1955-v-2017-only-12-remain-thanks-to-the-creative-destruction-that-fuels-economic-prosperity/ https://www.aei.org/carpe-diem/fortune-500-firms-1955-v-2017...
      - clouddrover 7y ago
        > what sort of argument is that? It isn't "an argument". It's simply a practical reality which contradicts your false preconceptions.
      - tomhoward 7y ago
        That 9/10 figure is misleading, if you browse the list here: https://money.cnn.com/magazines/fortune/fortune500_archive/full/1955/1.html https://money.cnn.com/magazines/fortune/fortune500_archive/f... Many more than 1/10 of those names are still dominant companies/brands, but some have gone through mergers or restructures, meaning the 1955 entity no longer exists but the business lives on and remains very strong. BP and Shell are on that 1955 list, and are obviously still very strong companies. According to the Lindy effect [1], the longer a company has existed, the longer it is likely to continue to exist. Both BP and Shell have long been diversified companies (even in the 1950s, Shell had vast business activities outside of petroleum), and have long been investing heavily in various forms of alternative energy. They're not likely to disappear in any foreseeable timeframe. [1] https://en.wikipedia.org/wiki/Lindy_effect https://en.wikipedia.org/wiki/Lindy_effect
- kube-system 7y ago
  It is advantageous to get a foot hold in competitive markets, for sure.... but these actions are also heavily motivated by ulterior motives: tax credits, PR/marketing, lobbying, undermining competitive threats, etc.
  - clouddrover 7y ago
    So just like every big business in every industry.

danans 7y ago

Doing this would defeat the only advantage hydrogen has, which is rapid fueling. To add to the inconvenience, you'll need to plug in both the electricity, and a hose to your supply of distilled water. Beyond that, the best case efficiency for such a hydrogen production process in an industrial setting is 80% (using a process which feeds waste heat back into the electrolysis reaction). From the hydrogen back to energy moving the wheels is at most 50% efficient, so a total plug to wheels efficiency of less than 40%. In the real world, it will be far less efficient than that (probably 25% at best), and very expensive to achieve in a practical car for sale, for the same reason that hydrogen fuel cells in cars are expensive today. That vs the typical plug to wheels efficiency of around 60% in today's electric vehicles. And such regenerative hydrogen fuel cells do not even exist for automotive applications today. This paper has several lifecycle efficiency graphs that explain aspects of this in some detail: https://www.mdpi.com/2032-6653/9/1/3 https://www.mdpi.com/2032-6653/9/1/3

Hypx 7y ago
https://www.sciencedirect.com/science/article/abs/pii/S036031991000340X https://www.sciencedirect.com/science/article/abs/pii/S03603... The best case scenario like you described is about 98%. FYI, 80% is already being hit by real world normal electrolysis reactions. It’s very likely we’re in the same position with fuel cell cars that solar was back in the late-2000s. Arguments that it is “too expensive” are really falling apart, especially considering that green hydrogen is around $2-3/kg today, and that platinum loading has dropped to around 10 grams for a car sized fuel cell.
- danans 7y ago
  > FYI, 80% is already being hit by real world normal electrolysis reactions. Not in a fuel-cell running in reverse in a car, though, which is what the GP was referring to. > especially considering that green hydrogen is around $2-3/kg today More like $3-7 per kg today [1]. And as that article (which is less than 1 month old) points out, producing green hydrogen would require an absolutely massive buildout of renewables, which would better be put to direct use without the conversion penalty to hydrogen. Hydrogen energy storage will still have its niche applications on the margins, but it is unlikely to catch up to the cost and availability advantages of batteries for cars in places where the existing electric grid reaches. 1. https://www.rechargenews.com/transition/a-wake-up-call-on-green-hydrogen-the-amount-of-wind-and-solar-needed-is-immense/2-1-776481 https://www.rechargenews.com/transition/a-wake-up-call-on-gr...

gok 7y ago

One issue is that you need a source of water. Another is that electrolysis is only around 70% efficient, whereas (say) lithium ion battery charging is more like 95% efficient.