5 ms·

> A liquid hydrogen tanker can carry nearly the same amount of energy as a liquid diesel tanker, noted Mike Roeth, NACFE executive director https://www.truckne

by _hypx 3y ago

> A liquid hydrogen tanker can carry nearly the same amount of energy as a liquid diesel tanker, noted Mike Roeth, NACFE executive director https://www.trucknews.com/sustainability/nacfe-takes-fresh-look-at-hydrogen-fuel-cells/1003174074/ https://www.trucknews.com/sustainability/nacfe-takes-fresh-l...

_aavaa_ 3y ago
A) Liquid hydrogen is stored at 20K, 20 degrees above absolute zero. Compressing and cooling hydrogen gas to 20K consumes ~30% of the energy content of the hydrogen. That tanker has a boil off rate of 0.3-0.6%. The thing you're storing it in is going to have a similar boil off range. B) "No hydrogen option will fully displace BEVs, noted Roeth"
- _hypx 3y ago
  You don’t consume any of the hydrogen to liquefy hydrogen. That comes from an external energy source. Smartly, it would just be the renewable energy used to make the hydrogen in the first place, making it potentially nearly free. BEVs will still exist as short-ranged urban vehicles. That is a niche, and in trucking that is a very small one too.
  - _aavaa_ 3y ago
    Wherever you get the energy to compress it from, you still need to spend ~30% of the energy content of the hydrogen to compress it to a liquid. There is no evidence to support the idea that BEVs (cars or trucks) will remain short-ranged urban vehicle. Even the "entry" level BEVs in NA, like the leaf, have gotten to EPA ranges of 360 km, a number that is only ever going to go up. Even trucking is slowly getting there as the battery tech improves. In Europe Mercedes is testing trucks, today, which hit 200-400 km before needing to charge [0]. That's not enough for long distance, but that doesn't matter. They can serve this market and when they're ready they can expand to longer ranges. Further, there is even less evidence that in applications where BEVs don't (and won't) work that hydrogen is the winning solution. What is hydrogen's go to market strategy? Introduce trucks for long range that have higher up front costs and higher total cost of ownership that diesel trucks, plus severely limit where you can drive since you depend on a (non-existent) hydrogen network? [0]: https://cleantechnica.com/2023/06/11/electric-semi-truck-drives-from-germany-to-turkey/ https://cleantechnica.com/2023/06/11/electric-semi-truck-dri...
    - _hypx 3y ago
      > The minimum theoretical energy to liquefy hydrogen from ambient (300 K, 1.01 bar) conditions is 3.3 kWh/kg LH2 or 3.9 kWh/kg LH2 with conversion to para-LH2 (which is standard practice) [1]. https://www.hydrogen.energy.gov/pdfs/9013_energy_requirements_for_hydrogen_gas_compression.pdf https://www.hydrogen.energy.gov/pdfs/9013_energy_requirement... It is not guaranteed to be 30%. And you're entirely basing your argument on the idea that batteries will get radically more advanced, while hydrogen technology will not. What happens when Toyota makes a Corolla powered by hydrogen at the same level of cost and the fuel is basically free (made from excess green energy)? Will BEVs really have much of a future in that scenario?
      - _aavaa_ 3y ago
        That's the theoretical limit and it's still ~10%. It's not guaranteed to be 30% no, but that's what they are now. > Actual liquefaction energy requirements are substantially higher, typically 10-13 kWh/kg LH2, depending on the size of the liquefaction operation [5,6]. > What happens when Toyota makes a Corolla powered by hydrogen at the same level of cost Pigs will fly. Toyota currently sells the Mirai, and it costs more than a model 3. The Mirai uses ~3x more electricity at the source to drive the same amount (assuming very optimistic efficiencies) and costs ~5x more to drive per mile. So I ask you, who will buy the Mirai instead of a model 3? The answer, based on sales data, is not many people. Because the Mirai is not even better for the environment unless you mange to source pure green energy hydrogen. So how will Toyota sell enough to bring down the cost of production? How long with it take for the hydrogen network to expand outside of california? A decade? And when that's happened, how will you convince the BEV drivers to sell their 10th gen BEV for a 3rd gen Hydrogen car? > and the fuel is basically free That is an absurd thing to claim. - Green electricity is not free since there's a Capex associated with it. - wind/solar does not suffer negative electricity rates in the same way that coal/gas/nuclear since they can be turned off on a whim. They do not have to generate excess energy if they don't want to. - Creating hydrogen from water is not free since there is expensive Capex associated with electrolyzers and other equipment required. - Combine the above 3 together and you'll find the idea of running your electrolyzers intermittenly for only a few hours when there's excess energy to be a laughable proposition from an economic point of view. - Compressing, storing, and transporting hydrogen is not free For reference, hydrogen from methane in the US currently sells for ~1.5$/kg. The idea that green hydrogren will get cheaper than that, much less free, is laughable.

by _hypx 3y ago

_aavaa_ 3y ago

A) Liquid hydrogen is stored at 20K, 20 degrees above absolute zero. Compressing and cooling hydrogen gas to 20K consumes ~30% of the energy content of the hydrogen. That tanker has a boil off rate of 0.3-0.6%. The thing you're storing it in is going to have a similar boil off range. B) "No hydrogen option will fully displace BEVs, noted Roeth"

_hypx 3y ago
You don’t consume any of the hydrogen to liquefy hydrogen. That comes from an external energy source. Smartly, it would just be the renewable energy used to make the hydrogen in the first place, making it potentially nearly free. BEVs will still exist as short-ranged urban vehicles. That is a niche, and in trucking that is a very small one too.
- _aavaa_ 3y ago
  Wherever you get the energy to compress it from, you still need to spend ~30% of the energy content of the hydrogen to compress it to a liquid. There is no evidence to support the idea that BEVs (cars or trucks) will remain short-ranged urban vehicle. Even the "entry" level BEVs in NA, like the leaf, have gotten to EPA ranges of 360 km, a number that is only ever going to go up. Even trucking is slowly getting there as the battery tech improves. In Europe Mercedes is testing trucks, today, which hit 200-400 km before needing to charge [0]. That's not enough for long distance, but that doesn't matter. They can serve this market and when they're ready they can expand to longer ranges. Further, there is even less evidence that in applications where BEVs don't (and won't) work that hydrogen is the winning solution. What is hydrogen's go to market strategy? Introduce trucks for long range that have higher up front costs and higher total cost of ownership that diesel trucks, plus severely limit where you can drive since you depend on a (non-existent) hydrogen network? [0]: https://cleantechnica.com/2023/06/11/electric-semi-truck-drives-from-germany-to-turkey/ https://cleantechnica.com/2023/06/11/electric-semi-truck-dri...
  - _hypx 3y ago
    > The minimum theoretical energy to liquefy hydrogen from ambient (300 K, 1.01 bar) conditions is 3.3 kWh/kg LH2 or 3.9 kWh/kg LH2 with conversion to para-LH2 (which is standard practice) [1]. https://www.hydrogen.energy.gov/pdfs/9013_energy_requirements_for_hydrogen_gas_compression.pdf https://www.hydrogen.energy.gov/pdfs/9013_energy_requirement... It is not guaranteed to be 30%. And you're entirely basing your argument on the idea that batteries will get radically more advanced, while hydrogen technology will not. What happens when Toyota makes a Corolla powered by hydrogen at the same level of cost and the fuel is basically free (made from excess green energy)? Will BEVs really have much of a future in that scenario?
    - _aavaa_ 3y ago
      That's the theoretical limit and it's still ~10%. It's not guaranteed to be 30% no, but that's what they are now. > Actual liquefaction energy requirements are substantially higher, typically 10-13 kWh/kg LH2, depending on the size of the liquefaction operation [5,6]. > What happens when Toyota makes a Corolla powered by hydrogen at the same level of cost Pigs will fly. Toyota currently sells the Mirai, and it costs more than a model 3. The Mirai uses ~3x more electricity at the source to drive the same amount (assuming very optimistic efficiencies) and costs ~5x more to drive per mile. So I ask you, who will buy the Mirai instead of a model 3? The answer, based on sales data, is not many people. Because the Mirai is not even better for the environment unless you mange to source pure green energy hydrogen. So how will Toyota sell enough to bring down the cost of production? How long with it take for the hydrogen network to expand outside of california? A decade? And when that's happened, how will you convince the BEV drivers to sell their 10th gen BEV for a 3rd gen Hydrogen car? > and the fuel is basically free That is an absurd thing to claim. - Green electricity is not free since there's a Capex associated with it. - wind/solar does not suffer negative electricity rates in the same way that coal/gas/nuclear since they can be turned off on a whim. They do not have to generate excess energy if they don't want to. - Creating hydrogen from water is not free since there is expensive Capex associated with electrolyzers and other equipment required. - Combine the above 3 together and you'll find the idea of running your electrolyzers intermittenly for only a few hours when there's excess energy to be a laughable proposition from an economic point of view. - Compressing, storing, and transporting hydrogen is not free For reference, hydrogen from methane in the US currently sells for ~1.5$/kg. The idea that green hydrogren will get cheaper than that, much less free, is laughable.