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I don't really see hydrogen going anywhere for cars (except maybe as range extender there might be case). However, for certain applications batteries become to

I don't really see hydrogen going anywhere for cars (except maybe as range extender there might be case). However, for certain applications batteries become to heavy to be practical, i.e. aviation, shipping, large trucks etc.

oblio 5y ago
Hydrogen could be great for the power grid.
- Robotbeat 5y ago
  Yeah, I think seasonal storage with hydrogen makes more sense than hydrogen trucks. People often underestimate just how heavy hydrogen fuel tanks are and the required cells and especially the huge radiator you need to get rid of all the heat. I once heard that the prototype for a Nikola hydrogen truck had a heat rejection system that required just as much power as a Nissan Leaf.
  - nickik 5y ago
    Seasonal storage is a total fantasy that has no practical application in the real world if you do the math on it. Building gigantic storage with 1 year cycle is a gigantic waste of resources and even if you assume electricity to be totally free to make it pay for itself the invest most per storage would have to be like 100x cheaper then current grid storage. Hydrogen in no shape or form will every be used as seasonal storage. Hydrogen is just another form of battery that would practically have to have a 6h to a few day cycle. And in that case there are better options.
    - Robotbeat 5y ago
      Nah, that’s not true if you use a container with cheap enough cost per storage-kWh, for instance salt caverns. In fact we ALREADY use them for seasonal natural gas storage. The references to this toy model show how to get extremely low cost per storage-kWh, as cheap as 0.7 € per kWh. (So amortized over 20 years, that’s a pretty small addition to the energy cost). https://model.energy https://model.energy Details on the salt cavern hydrogen storage: https://doi.org/10.1016/j.energy.2018.05.059 https://doi.org/10.1016/j.energy.2018.05.059 Or think in context of this liquid air (or compressed air) battery. If you can get liquid air or compressed air batteries to cost $300/kWh or so, hydrogen in the same container compressed to the same degree can store about 100 times the energy (especially if sub-cooled). So the storage cost (if dominated by the container structure) drops by a factor of ~100. That’s $3/kWh for storage, if you don’t use salt caverns. Not great if only amortized over 20 years (plus the bad round-trip efficiency), but also not terrible if it’s only used for like 5% of the electricity needs. And that’s the real issue with seasonal storage: no one needs it really until you get to 95-100% decarbonization of the grid. Otherwise, best to use like a few gas turbines or something as backup/seasonal power. So investing a bunch of storage when you haven’t even built out a bunch of solar or wind, yet, is kind of suboptimal. Good to do demo plants, though, so you can get ready with the tech for when you DO need to decarbonize that last 5% or so.

oblio 5y ago

Hydrogen could be great for the power grid.

Robotbeat 5y ago
Yeah, I think seasonal storage with hydrogen makes more sense than hydrogen trucks. People often underestimate just how heavy hydrogen fuel tanks are and the required cells and especially the huge radiator you need to get rid of all the heat. I once heard that the prototype for a Nikola hydrogen truck had a heat rejection system that required just as much power as a Nissan Leaf.
- nickik 5y ago
  Seasonal storage is a total fantasy that has no practical application in the real world if you do the math on it. Building gigantic storage with 1 year cycle is a gigantic waste of resources and even if you assume electricity to be totally free to make it pay for itself the invest most per storage would have to be like 100x cheaper then current grid storage. Hydrogen in no shape or form will every be used as seasonal storage. Hydrogen is just another form of battery that would practically have to have a 6h to a few day cycle. And in that case there are better options.
  - Robotbeat 5y ago
    Nah, that’s not true if you use a container with cheap enough cost per storage-kWh, for instance salt caverns. In fact we ALREADY use them for seasonal natural gas storage. The references to this toy model show how to get extremely low cost per storage-kWh, as cheap as 0.7 € per kWh. (So amortized over 20 years, that’s a pretty small addition to the energy cost). https://model.energy https://model.energy Details on the salt cavern hydrogen storage: https://doi.org/10.1016/j.energy.2018.05.059 https://doi.org/10.1016/j.energy.2018.05.059 Or think in context of this liquid air (or compressed air) battery. If you can get liquid air or compressed air batteries to cost $300/kWh or so, hydrogen in the same container compressed to the same degree can store about 100 times the energy (especially if sub-cooled). So the storage cost (if dominated by the container structure) drops by a factor of ~100. That’s $3/kWh for storage, if you don’t use salt caverns. Not great if only amortized over 20 years (plus the bad round-trip efficiency), but also not terrible if it’s only used for like 5% of the electricity needs. And that’s the real issue with seasonal storage: no one needs it really until you get to 95-100% decarbonization of the grid. Otherwise, best to use like a few gas turbines or something as backup/seasonal power. So investing a bunch of storage when you haven’t even built out a bunch of solar or wind, yet, is kind of suboptimal. Good to do demo plants, though, so you can get ready with the tech for when you DO need to decarbonize that last 5% or so.