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Yeah, anything but green hydrogen is just a complicated way of keeping the status quo, fossil fuel oriented system in place. There might be a small benefit to g

Yeah, anything but green hydrogen is just a complicated way of keeping the status quo, fossil fuel oriented system in place. There might be a small benefit to global warming (not found in this paper), but it’s using up a finite amount of capture space. I do think we can probably get a lot better at capturing methane leaks, though. It’s low hanging fruit. …and even green hydrogen is much less efficient for heating and propulsion than heat pumps and battery/direct-electric. Especially in the early days when we are still working to increase the energy payback of renewables, this is not helpful! We need high efficiency usage of electricity. Making hydrogen is something you shouldn’t do unless there aren’t alternatives. We don’t need hydrogen for heat, for transport, or for storage (possible exception being seasonal storage once you’ve surpassed 95% clean electricity… no point in hydrogen storage if you’re still only a 50% clean grid). Hydrogen trucks are more expensive (to buy and ESPECIALLY a to operate) and not necessarily any more range (possible exception if you use liquid hydrogen). We do use hydrogen industrially for all ammonia production and (believe it or not) all new iron ore reduction plants (DRI/HBI plants) in the US (they use syngas usually, a mix of hydrogen and CO, usually made from natural gas but it could be made almost entirely with hydrogen), so it’s not like we won’t find a use for the hydrogen we might produce from excess renewable power.

shalmanese 5y ago
Well, also that green hydrogen is a drop in replacement for blue/grey hydrogen. The hard part is building all the infrastructure. If we can build the infrastructure on blue/grey and then gradually transition to green over time, it's an easier feat than waiting until we have economical green hydrogen before starting to build.
- Robotbeat 5y ago
  Except we already HAVE massive demand for blue/gray hydrogen (for fertilizer and steel), and the infrastructure for electric vehicles (cars, trains, and trucks) is FAR cheaper than it is for hydrogen. It doesn’t make sense to invest in expensive dead-end infrastructure when we know it is fundamentally, significantly less efficient from a physics standpoint.
  - diarrhea 5y ago
    Efficiency is not a huge concern when highly fluctuating energy from renewable sources is involved. You either have zero efficiency because it goes to waste for lack of storage, or some efficiency through hydrogen (electrolysis).
    - ben_w 5y ago
      The options are not {hydrogen, waste}, they are {batteries, thermal storage, pumped hydroelectric, Sabatier process methane[0], …, hydrogen, waste}. [0] I’m not a civil engineer and I can’t estimate the costs of upgrading existing methane pipes to cope with hydrogen, but people write about it being a thing, so this may or may not be better than pure hydrogen even if it’s less energy efficient; but the point is there are many options not just two
      - diarrhea 5y ago
        Not wrong! However: - batteries: not available large-scale - thermal storage: potentially terribly inefficient (but as I said, yes it's at least something!) - pumped hydroelectric: where I'm from, only available to a tiny fraction of the country - Sabatier process methane: that's a possibility I guess, more inefficient though My point being, yes you're right, there's many more storage solutions, but hydrogen seems to trump most. Might as well use that as much as possible. > [0] I’m not a civil engineer and I can’t estimate the costs of upgrading existing methane pipes to cope with hydrogen, but people write about it being a thing The issue is also that the recipients would need to deal with the pure hydrogen they're getting. Residential boilers for natural gas can't, for example. New models are required.
        Robotbeat 5y ago
        The deal with hydrogen is that electrolyzers cost a lot of money & round trip efficiency is bad anyway, so you’ll want battery storage for daily cycling and a combination of solar, wind, and good distribution. A small amount of curtailment is fine, in fact most power plants don’t operate 24/7 even when fuel is cheap, and you could consider that “curtailment,” too, but it’s just accepted that it’s okay to idle a power plant if it’s output isn’t needed (the only difference with solar and wind is their fuel is free). But once you use batteries and good distribution, there isn’t much curtailment needed. Hydrogen electrolyzers just using “free” electricity 5% of the time is crazy expensive… it’s 20 times as expensive (from a capital standpoint) as running 24/7. And all of this is fine until we get to ~95% clean/renewable grids. Maybe at that point it’d be worth using hydrogen fir seasonal storage. But even then, you’ll still have some curtailment because otherwise your electrolyzer is too expensive. Check out https://model.energy https://model.energy for how this would work.
- jillesvangurp 5y ago
  That's more or less the pitch of the oil industry. And they seem to be very successful in getting billions in subsidy to do it. That's on top of the subsidies they are getting to exploit fossil fuels. The problem is that this is just green washing their "lets put more co2" in the atmosphere strategy for an other few decades. Because that's exactly what this is. It legitimizes that strategy and they are lobbying hard for this. Nevertheless, transitioning grey hydrogen to blue hydrogen is probably a good thing. There's a lot of demand for hydrogen already in various industrial applications that are currently mostly using grey hydrogen. And transitioning more of our industry to hydrogen is key to de-carbonizing it. So, whether we like it or not, the hydrogen market is going to grow a lot in the next decades and it is probably going to be mostly blue+grey hydrogen for the foreseeable future produced by oil and gas companies and only little bits of green hydrogen. The problem with green hydrogen is that it is magnitudes more expensive than blue hydrogen, which in turn is more expensive than the grey variety. Green hydrogen requires renewable energy and green hydrogen is just not a particularly efficient application of that energy as you need rather a lot of it. A kilo of hydrogen is the equivalent of about 33 kwh. The market price of hydrogen varies wildly depending on how it is produced, transported and stored. The green variety is about 7$ per kilo. Or about 21 cents per kwh. Grey hydrogen (the dirty stuff) is about a dollar in the best cases. That's still about 3 cents per kwh. Grid prices for renewables vary widely but in the areas most likely to get involved with green hydrogen (i.e. middle east) they are between 1 and 2 cents per kwh for some recent renewable setups. So that's a factor of 3-21x depending on how you look at it. Blue hydrogen is somewhere in the bottom of that range.
  - Robotbeat 5y ago
    It’s worse than that. 1kg of hydrogen may be 33kWh from a heating value perspective, but it only gets you like 60 miles of range in a car like a Mirai. Compared to a Model 3, which gets 4 miles per kWh, that puts the hydrogen at roughly 15kWh of useful energy. Also, the automotive price of hydrogen is about $13-16/kg in the only place with hydrogen fueling stations in the US, ie Southern California.
    - throwawayzRUU6f 5y ago
lamontcg 5y ago
There's a hell of a lot of denial and negotiation when it comes to the carbon-based economy. There is a painful amount of searching for some way to keep on digging up carbon out of the ground and turn it into something green. So far the only real solutions are to leave the carbon in the ground and switch to wind/solar/etc. We need to get past the denial/anger/negotiation/depression phases and just hit the acceptance phase of post-carbon energy.
- Gibbon1 5y ago
  Yeah because in the 20th century Power with a capital P was almost wholly based on digging and pumping carbon out of the ground.
benhurmarcel 5y ago
> We don’t need hydrogen […] for transport We’ll need it for aviation.
- Robotbeat 5y ago
  Hydrogen for aviation doesn’t solve the high altitude water emissions problem of aviation and in fact makes it potentially worse. This effect is just as bad a CO2 emissions. Battery-electric can eliminate both. In the mid-term, battery electric can serve all short haul routes, which is about half of aviation passenger miles, and probably most medium and long haul routes can be split up into short haul routes (the hub and spoke model means that you end up doing multiple flights anyway for most random city pairs and the smaller initial battery electric aircraft will be more granular, meaning you can do more direct flights, or at least more flights that go in the right direction instead of needing to double back to hubs). Long term, battery-electric can do 4000-5000km long haul routes, and perhaps even supersonic flights.
  - benhurmarcel 5y ago
    That’s just wishful thinking. So far nothing shows that batteries would allow even most current “short” flights by airliners, only some trivial extremely short regional connection flights at most. That’s also why no major aviation company is going towards batteries for airliners. Also, burning H2 does generate heat and water emissions, but it’s not the case with fuel cells. Those can be literally 0-emissions.
    - Robotbeat 5y ago
      Nope. It’s not wishful thinking, it’s my day job. It pops out of analysis of what aerodynamics advances are possible, eg work by Pfenninger and others which is decades old. It’s fascinating how some confuse their own lack of familiarity with the state of the art research on this with lack of any sound ability. Boeing and Airbus have both invested millions in startups that are working on battery electric aircraft. But beyond that, it wasn’t Toyota or VW that made the Model S and the Model 3. Why would we expect a massive, slow-moving behemoth to be at the forefront of electric flight if the massive, slow-moving behemoths of land transport weren’t at the forefront of practical long distance electric cars? Companies such as Eviation, MagniX, and Bye Aerospace have promising approaches for the roughly 1000km range, with more advanced approaches (longer wings, pressurized cabin enabling higher altitudes, better battery chemistries, etc) enabling all short haul flights. Long-haul is a much bigger challenge, but still possible. And dropping water from high altitude will still cause water emissions. You’d need operational complexity such as freezing the water into pellets, or dumping the water occasionally at low altitudes. And compressed hydrogen has terrible energy density so you’ll want liquid hydrogen, which is still the lowest density liquid known to humankind plus is also almost the deepest cryogenic liquid, with a bunch of energy required for liquefaction and some pretty annoying/dangerous handling issues during refueling. Sure, it could be done, but it’s going to be harder than people think and the poor round trip efficiency is going to limit the economic case for it versus battery-electric.

shalmanese 5y ago

Well, also that green hydrogen is a drop in replacement for blue/grey hydrogen. The hard part is building all the infrastructure. If we can build the infrastructure on blue/grey and then gradually transition to green over time, it's an easier feat than waiting until we have economical green hydrogen before starting to build.

Robotbeat 5y ago
Except we already HAVE massive demand for blue/gray hydrogen (for fertilizer and steel), and the infrastructure for electric vehicles (cars, trains, and trucks) is FAR cheaper than it is for hydrogen. It doesn’t make sense to invest in expensive dead-end infrastructure when we know it is fundamentally, significantly less efficient from a physics standpoint.
- diarrhea 5y ago
  Efficiency is not a huge concern when highly fluctuating energy from renewable sources is involved. You either have zero efficiency because it goes to waste for lack of storage, or some efficiency through hydrogen (electrolysis).
  - ben_w 5y ago
    The options are not {hydrogen, waste}, they are {batteries, thermal storage, pumped hydroelectric, Sabatier process methane[0], …, hydrogen, waste}. [0] I’m not a civil engineer and I can’t estimate the costs of upgrading existing methane pipes to cope with hydrogen, but people write about it being a thing, so this may or may not be better than pure hydrogen even if it’s less energy efficient; but the point is there are many options not just two
    - diarrhea 5y ago
      Not wrong! However: - batteries: not available large-scale - thermal storage: potentially terribly inefficient (but as I said, yes it's at least something!) - pumped hydroelectric: where I'm from, only available to a tiny fraction of the country - Sabatier process methane: that's a possibility I guess, more inefficient though My point being, yes you're right, there's many more storage solutions, but hydrogen seems to trump most. Might as well use that as much as possible. > [0] I’m not a civil engineer and I can’t estimate the costs of upgrading existing methane pipes to cope with hydrogen, but people write about it being a thing The issue is also that the recipients would need to deal with the pure hydrogen they're getting. Residential boilers for natural gas can't, for example. New models are required.
      - Robotbeat 5y ago
        The deal with hydrogen is that electrolyzers cost a lot of money & round trip efficiency is bad anyway, so you’ll want battery storage for daily cycling and a combination of solar, wind, and good distribution. A small amount of curtailment is fine, in fact most power plants don’t operate 24/7 even when fuel is cheap, and you could consider that “curtailment,” too, but it’s just accepted that it’s okay to idle a power plant if it’s output isn’t needed (the only difference with solar and wind is their fuel is free). But once you use batteries and good distribution, there isn’t much curtailment needed. Hydrogen electrolyzers just using “free” electricity 5% of the time is crazy expensive… it’s 20 times as expensive (from a capital standpoint) as running 24/7. And all of this is fine until we get to ~95% clean/renewable grids. Maybe at that point it’d be worth using hydrogen fir seasonal storage. But even then, you’ll still have some curtailment because otherwise your electrolyzer is too expensive. Check out https://model.energy https://model.energy for how this would work.
jillesvangurp 5y ago
That's more or less the pitch of the oil industry. And they seem to be very successful in getting billions in subsidy to do it. That's on top of the subsidies they are getting to exploit fossil fuels. The problem is that this is just green washing their "lets put more co2" in the atmosphere strategy for an other few decades. Because that's exactly what this is. It legitimizes that strategy and they are lobbying hard for this. Nevertheless, transitioning grey hydrogen to blue hydrogen is probably a good thing. There's a lot of demand for hydrogen already in various industrial applications that are currently mostly using grey hydrogen. And transitioning more of our industry to hydrogen is key to de-carbonizing it. So, whether we like it or not, the hydrogen market is going to grow a lot in the next decades and it is probably going to be mostly blue+grey hydrogen for the foreseeable future produced by oil and gas companies and only little bits of green hydrogen. The problem with green hydrogen is that it is magnitudes more expensive than blue hydrogen, which in turn is more expensive than the grey variety. Green hydrogen requires renewable energy and green hydrogen is just not a particularly efficient application of that energy as you need rather a lot of it. A kilo of hydrogen is the equivalent of about 33 kwh. The market price of hydrogen varies wildly depending on how it is produced, transported and stored. The green variety is about 7$ per kilo. Or about 21 cents per kwh. Grey hydrogen (the dirty stuff) is about a dollar in the best cases. That's still about 3 cents per kwh. Grid prices for renewables vary widely but in the areas most likely to get involved with green hydrogen (i.e. middle east) they are between 1 and 2 cents per kwh for some recent renewable setups. So that's a factor of 3-21x depending on how you look at it. Blue hydrogen is somewhere in the bottom of that range.
- Robotbeat 5y ago
  It’s worse than that. 1kg of hydrogen may be 33kWh from a heating value perspective, but it only gets you like 60 miles of range in a car like a Mirai. Compared to a Model 3, which gets 4 miles per kWh, that puts the hydrogen at roughly 15kWh of useful energy. Also, the automotive price of hydrogen is about $13-16/kg in the only place with hydrogen fueling stations in the US, ie Southern California.
  - throwawayzRUU6f 5y ago

lamontcg 5y ago

There's a hell of a lot of denial and negotiation when it comes to the carbon-based economy. There is a painful amount of searching for some way to keep on digging up carbon out of the ground and turn it into something green. So far the only real solutions are to leave the carbon in the ground and switch to wind/solar/etc. We need to get past the denial/anger/negotiation/depression phases and just hit the acceptance phase of post-carbon energy.

Gibbon1 5y ago
Yeah because in the 20th century Power with a capital P was almost wholly based on digging and pumping carbon out of the ground.

benhurmarcel 5y ago

> We don’t need hydrogen […] for transport We’ll need it for aviation.

Robotbeat 5y ago
Hydrogen for aviation doesn’t solve the high altitude water emissions problem of aviation and in fact makes it potentially worse. This effect is just as bad a CO2 emissions. Battery-electric can eliminate both. In the mid-term, battery electric can serve all short haul routes, which is about half of aviation passenger miles, and probably most medium and long haul routes can be split up into short haul routes (the hub and spoke model means that you end up doing multiple flights anyway for most random city pairs and the smaller initial battery electric aircraft will be more granular, meaning you can do more direct flights, or at least more flights that go in the right direction instead of needing to double back to hubs). Long term, battery-electric can do 4000-5000km long haul routes, and perhaps even supersonic flights.
- benhurmarcel 5y ago
  That’s just wishful thinking. So far nothing shows that batteries would allow even most current “short” flights by airliners, only some trivial extremely short regional connection flights at most. That’s also why no major aviation company is going towards batteries for airliners. Also, burning H2 does generate heat and water emissions, but it’s not the case with fuel cells. Those can be literally 0-emissions.
  - Robotbeat 5y ago
    Nope. It’s not wishful thinking, it’s my day job. It pops out of analysis of what aerodynamics advances are possible, eg work by Pfenninger and others which is decades old. It’s fascinating how some confuse their own lack of familiarity with the state of the art research on this with lack of any sound ability. Boeing and Airbus have both invested millions in startups that are working on battery electric aircraft. But beyond that, it wasn’t Toyota or VW that made the Model S and the Model 3. Why would we expect a massive, slow-moving behemoth to be at the forefront of electric flight if the massive, slow-moving behemoths of land transport weren’t at the forefront of practical long distance electric cars? Companies such as Eviation, MagniX, and Bye Aerospace have promising approaches for the roughly 1000km range, with more advanced approaches (longer wings, pressurized cabin enabling higher altitudes, better battery chemistries, etc) enabling all short haul flights. Long-haul is a much bigger challenge, but still possible. And dropping water from high altitude will still cause water emissions. You’d need operational complexity such as freezing the water into pellets, or dumping the water occasionally at low altitudes. And compressed hydrogen has terrible energy density so you’ll want liquid hydrogen, which is still the lowest density liquid known to humankind plus is also almost the deepest cryogenic liquid, with a bunch of energy required for liquefaction and some pretty annoying/dangerous handling issues during refueling. Sure, it could be done, but it’s going to be harder than people think and the poor round trip efficiency is going to limit the economic case for it versus battery-electric.