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You might know: why do large electrolytic hydrogen projects being built or planned today still use alkaline or PEM electrolyzers? I haven't seen any announcemen

You might know: why do large electrolytic hydrogen projects being built or planned today still use alkaline or PEM electrolyzers? I haven't seen any announcements where projects are using solid oxide cells. I assumed that the technology wasn't commercially available yet.

darksaints 7y ago
I'm not aware of any large electrolysis projects using PEMs, unless the purpose is for research and development. I know of a few using alkaline cells, but those are quite efficient. At least as efficient as solid oxide cells, just a bit harder to work with. Most of the research and development for solid oxide cells is for fuel cell usage, with a focus on usage of liquid or gaseous hydrocarbon fuels, due to the easier technological transition (I'm working on a project like this). Without subsidies or carbon taxes, electrolysis is likely to be done only on a small scale. At large scales, hydrogen from methane is still cheaper, and there is no penalty for carbon emissions, and consumers typically buy in large quantities at limited endpoints. However, if fuel cell vehicles (more likely to be commercial vehicles than personal vehicles at this point, as the economics are more in their favor) become more common, there will be growing benefits to electrolysis because the logistics are so much simpler for a large amount of end points.
- philipkglass 7y ago
  As in this recent story: "World's largest green-hydrogen plant begins operation in Austria" https://www.rechargenews.com/transition/worlds-largest-green-hydrogen-plant-begins-operation-in-austria/2-1-708381 https://www.rechargenews.com/transition/worlds-largest-green... It's using PEM technology from Siemens. It reports that an even larger PEM project should finish construction next year. It mentions one other project, even larger but further out, using alkaline electrolyzers. They are all part of decarbonization research projects, but operating at megawatts to tens of megawatts scales.

darksaints 7y ago

I'm not aware of any large electrolysis projects using PEMs, unless the purpose is for research and development. I know of a few using alkaline cells, but those are quite efficient. At least as efficient as solid oxide cells, just a bit harder to work with. Most of the research and development for solid oxide cells is for fuel cell usage, with a focus on usage of liquid or gaseous hydrocarbon fuels, due to the easier technological transition (I'm working on a project like this). Without subsidies or carbon taxes, electrolysis is likely to be done only on a small scale. At large scales, hydrogen from methane is still cheaper, and there is no penalty for carbon emissions, and consumers typically buy in large quantities at limited endpoints. However, if fuel cell vehicles (more likely to be commercial vehicles than personal vehicles at this point, as the economics are more in their favor) become more common, there will be growing benefits to electrolysis because the logistics are so much simpler for a large amount of end points.

philipkglass 7y ago
As in this recent story: "World's largest green-hydrogen plant begins operation in Austria" https://www.rechargenews.com/transition/worlds-largest-green-hydrogen-plant-begins-operation-in-austria/2-1-708381 https://www.rechargenews.com/transition/worlds-largest-green... It's using PEM technology from Siemens. It reports that an even larger PEM project should finish construction next year. It mentions one other project, even larger but further out, using alkaline electrolyzers. They are all part of decarbonization research projects, but operating at megawatts to tens of megawatts scales.