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Resorting to ad hominems only demonstrates that you're not interested in engaging productively. So this claim about having infrastructure to manipulate hydroge

Resorting to ad hominems only demonstrates that you're not interested in engaging productively. So this claim about having infrastructure to manipulate hydrogen is referring to the chemical industry, where hydrogen frequently used as an input. You're right that the chemical industry does use hydrogen and we have infrastructure to use it in the Haber process, and refining hydrocarbons and more. But this infrastructure doesn't translate to using hydrogen as a form of energy storage. The US has less than 1,000 miles of hydrogen pipeline [1]. Most hydrogen production facilities are located close to the point of demand. Our experience manipulating hydrogen has taught us that it's important to minimize to minimize the amount of transport required. Also, almost all of these many millions of tons of hydrogen produced each year are produced through steam reformation [2]. This is not carbon neutral, and renewable hydrogen production must be done through electrolysis or thermochemical hydrogen production instead. By comparison, there's a larger need to transport hydrogen if we're using hydrogen as a form of energy storage. Hydrogen storage is underground, and electrolysis needs to be done by a source of water. The source and destination have different required geographic features - transport is unavoidable. Alternatively you could pipe the water to the electrolysis plant, but then you're moving 9 times as much mass through the pipeline - water is 1 part hydrogen to 8 parts oxygen by mass. So the claim that we have extensive infrastructure in manipulating hydrogen wasn't a misunderstanding in that natural gas infrastructure can be used to transport hydrogen. It was a misunderstanding in that the infrastructure used to manipulate hydrogen in the context of the chemical industry translates into infrastructure for renewable hydrogen production, and hydrogen transport and storage. It doesn't: most of our hydrogen is produced through steam reformation, and our hydrogen infrastructure is built around minimizing need to transport and store hydrogen. 1. https://en.wikipedia.org/wiki/Hydrogen_infrastructure#:~:text=Hydrogen%20pipeline%20transport,-Hydrogen%20pipeline%20transport&text=As%20of%202004%2C%20there%20are,(1%2C497%20km)%20in%20Europe https://en.wikipedia.org/wiki/Hydrogen_infrastructure#:~:tex.... 2. https://en.wikipedia.org/wiki/Hydrogen_production https://en.wikipedia.org/wiki/Hydrogen_production

reitzensteinm 6y ago
If water access is the bottleneck, you can build storage and reuse it. 1 GWh of hydrogen is equal to 30 tons, or 270 tons of water. That's so small you can literally order a prefab off the internet here in Australia, installed and delivered for $10k. Extrapolated, that would represent $0.01/kWh in capital costs, or a complete rounding error of costs over the lifetime of the plant. You could even truck it in from a thousand miles away without really impacting the cost very much. To explore the problem a different way, here in Australia, 8 million megaliters of water was used in farming in the last year. Total energy consumption (not just electricity) in the same period was 1714 TWh. Storing 3 weeks of our energy needs would require 26,700 megaliters of water be converted to hydrogen, or 0.3% of the amount yearly used in farming, already distributed in regional areas.
- Manfredo_1 6y ago
  The challenge lies in moving the water, not in building a container to store it. > You could even truck it in from a thousand miles away without really impacting the cost very much. Lets' do the math. Trucking costs ~$.15 per short ton per mile as per Google. So shipping 270 tons over 1,000 miles works out to $40,000. And you're using the thermal energy density of hydrogen, not the electrical energy density - as in, accounting for inefficiency of electricity generation. 1 GWh thermal is typically 500 MWh electrical for both fuel cells and turbines. The actual cost would be double that, given that most systems are 40-60% efficient. So if by "without really impacting the cost vey much" you mean "increasing the cost by a factor of 5-9x", then sure. Moving large amounts of water is energy intensive, most infrastructure built to move water relies on gravity to move water from alpine reservoirs to lowlands. And unless you're capturing the output of whatever you're using to transform hydrogen back into electricity, then this is a recurring cost not a capital cost. This is easier to do for some implementations, like electrochemical cells, but much harder for gas turbines.
  - reitzensteinm 6y ago
    Yeah, I mean in the case where you're recapturing the water. Trucking it to use it once is madness, and storage isn't really relevant if you've got a pipeline or a river to draw from. You're totally right about thermal vs electrical, even with a fuel cell.
    - pfdietz 6y ago
      If the volume involved is high enough to be problematic, it's high enough to justify building pipelines. The cost of trucking is irrelevant.
      - reitzensteinm 6y ago
        Right. I was just sketching out that you could build it self contained in a desert if you really had to and still make it economical. Ad absurdum only, not a serious suggestion.

reitzensteinm 6y ago

If water access is the bottleneck, you can build storage and reuse it. 1 GWh of hydrogen is equal to 30 tons, or 270 tons of water. That's so small you can literally order a prefab off the internet here in Australia, installed and delivered for $10k. Extrapolated, that would represent $0.01/kWh in capital costs, or a complete rounding error of costs over the lifetime of the plant. You could even truck it in from a thousand miles away without really impacting the cost very much. To explore the problem a different way, here in Australia, 8 million megaliters of water was used in farming in the last year. Total energy consumption (not just electricity) in the same period was 1714 TWh. Storing 3 weeks of our energy needs would require 26,700 megaliters of water be converted to hydrogen, or 0.3% of the amount yearly used in farming, already distributed in regional areas.

Manfredo_1 6y ago
The challenge lies in moving the water, not in building a container to store it. > You could even truck it in from a thousand miles away without really impacting the cost very much. Lets' do the math. Trucking costs ~$.15 per short ton per mile as per Google. So shipping 270 tons over 1,000 miles works out to $40,000. And you're using the thermal energy density of hydrogen, not the electrical energy density - as in, accounting for inefficiency of electricity generation. 1 GWh thermal is typically 500 MWh electrical for both fuel cells and turbines. The actual cost would be double that, given that most systems are 40-60% efficient. So if by "without really impacting the cost vey much" you mean "increasing the cost by a factor of 5-9x", then sure. Moving large amounts of water is energy intensive, most infrastructure built to move water relies on gravity to move water from alpine reservoirs to lowlands. And unless you're capturing the output of whatever you're using to transform hydrogen back into electricity, then this is a recurring cost not a capital cost. This is easier to do for some implementations, like electrochemical cells, but much harder for gas turbines.
- reitzensteinm 6y ago
  Yeah, I mean in the case where you're recapturing the water. Trucking it to use it once is madness, and storage isn't really relevant if you've got a pipeline or a river to draw from. You're totally right about thermal vs electrical, even with a fuel cell.
  - pfdietz 6y ago
    If the volume involved is high enough to be problematic, it's high enough to justify building pipelines. The cost of trucking is irrelevant.
    - reitzensteinm 6y ago
      Right. I was just sketching out that you could build it self contained in a desert if you really had to and still make it economical. Ad absurdum only, not a serious suggestion.