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Hydrogen could be interesting as energy storage in this configuration. And hydrogen-based kerosene would make airplanes carbon-neutral but is really energy inte

by Adrig 5y ago

Hydrogen could be interesting as energy storage in this configuration. And hydrogen-based kerosene would make airplanes carbon-neutral but is really energy intensive

seb1204 5y ago
No it is not. Stop the straw man argument. Hydrogen has been talked about 10 years ago and the technology is still in its beginnings compared to most solar components nowadays. Hydrogen is also increasingly used by the fissile/carbon industry as a decoy to keep their gas on longer to make hydrogen.
- iamthemonster 5y ago
  "Hydrogen" is a fundamentally different thing to "solar". There is no "straw man argument" being made because it's comparing apples and pears. The only purpose of hydrogen is to make energy in one point in space & time and then use it in another point of your choice without CO2 emissions. Solar is to convert sunlight to electrical energy, but you don't get to control when the sun is shining. The technology to generate hydrogen is also completely mature and has been since before I was born, whether we are talking steam methane reforming or electrolysis. It's just not very cheap.
  - smegger001 5y ago
    except hydrogen is a horrible option. It is hard to store safely, it is highly explosive, energy expensive to produce vs the energy you get back out, it damages its own holding vessels via hydrogen embitterment, outside of a few niche areas it in generally a bad option.
    - hef19898 5y ago
      No idea about energy consumption, so I would assume using dirt cheap solar in remote places with defacto zero variable production costs (over simplified, but this is one reason wind and solar are pricing out other sources on the German spot market which ignores fix costs) might change that. Long term storage of hydrogen is quite easy so. It can be stored in thermal oil, rendering it inert. In thay form it isn't even considered dangerous goods for transportation anymore. Source: I consulted a green hydrogen project on logistics a while ago.
    - labawi 5y ago
      > highly explosive It's only explosive when mixed with air in confined places, as is gasoline, LPG, CNG, steel, wood and flour. Unlike most others, confinement is a requirement, otherwise it escapes too quickly. See [1] for comparison. > hard to store safely, damages its own holding vessels For these reasons I suggest we should produce and store methane, though hydrogen issues aren't a showstopper and hydrogen fuel cells are more efficient. [1] https://hydrogen.wsu.edu/2017/03/17/so-just-how-dangerous-is-hydrogen-fuel/ https://hydrogen.wsu.edu/2017/03/17/so-just-how-dangerous-is...
      - makomk 5y ago
        Hydrogen is highly explosive at almost all concentrations in air, extremely easy to ignite, and leaks through most widely-used materials. It's much worse in all these aspects than common fuels like gasoline, LPG, natural gas, etc.
        labawi 5y ago
        While the claims are (likely) technically true, if you are trying to insinuate it is less safe, then that is a false conclusion. As an example, many garages ban LPG cars, but don't care about CNG, AFAICT, because LPG can pool around on the bottom, but methane is light and easily escapes. Hydrogen is even lighter and harder to contain. The link [1] has compelling arguments.
    - pfdietz 5y ago
      > hard to store safely It's far easier to store it (underground, as compressed gas; this is a demonstrated technology) than it is to store energy in batteries. The cost/energy capacity can be extremely low, ~ $1/kWh equivalent.
      - smegger001 5y ago
        at that point we are no longer looking at a fuel for mobile vehicles and other technologies become better without the lossful need for electrolysis. pumped storage is highly effective for example.
        pfdietz 5y ago
        Sure, but the cost per unit of energy storage capacity is also higher for PHES. So PHES (and batteries on one side, and hydrogen on the other) have different storage use cases. In general combining several storage technologies like these can end up being better than using just one.
    - lovemenot 5y ago
      If you can acquire hydrogen economically, it can be converted to ammonia cheaply. For many industrial processes, ammonia is a well-established common feedstock, having none of the issues of hydrogen you mention. Here in Japan, some Combined Cycle Gas Turbine plants are already running with 10% ammonia blend. I think you are right about pure hydrogen, but I can see green-hydrogen-into-ammonia as viable for many applications including heavy transportation (train, ship, truck). We just need much more economic electrolysis, because hydrogen is almost always produced from fossil fuels today.
      - nickik 5y ago
        I learned about this only 10 years ago and then it was to late already, but had they started to convert to Flex-Fuel Vehicle in the 90s it would have meant much cheaper fuel in the 2000s (because natural gas to methanol is cheap and gas was cheap). Plus you could easily replace it with solar produced methanol overtime. EV however killed the need for that for the most part. Today I don't really think synfuels have much of a application. Batteries and storing energy electrically will win. It will not be so long until you can basically do Iron-Silicon battery for a very cheap price. Or if we finally figure Sulfer we could have amazing batteries for super cheap.
  - diordiderot 5y ago
    Hydrogen has very low energy density compared to gasoline. Like how diesel has more energy than gasoline. It also has a terrible efficiency. I think you lose ~70% from electrolysis. You also have the problem that most hydrogen today is made from petroleum!
    - kolinko 5y ago
      That matters for hydrogen cars, which are a terrible idea. But for grid storage energy density doesn't matter too much. Hydrogen, with all it's downsides, is awesome for long term storage because it scales sublinearly with capacity.
  - pfdietz 5y ago
    > The technology to generate hydrogen is also completely mature That depends on what metric you are looking at. Efficiency? Perhaps. Cost/kW of the electrolyzer? Not true at all. Also, the use case for electrolyzers has changed: from converting relatively pricy baseload power to hydrogen to converting cheap intermittent power to hydrogen. For the latter you want to trade efficiency for lower capital cost.
- frosted-flakes 5y ago
  What straw man argument? You can refute claims made without resorting to such accusations.
- ReptileMan 5y ago
  The idea is to use hydrogen as easily scalable battery. All of the things that prevent fuel cells from being easily applicable in cars are not such a big factor in closed loop system.
- Svoka 5y ago
  Stop using "straw man" inappropriately. That's just not what it means.
- Adrig 5y ago
  I'm not sure you're familiar with straw man arguments. I know the drawbacks of hydrogen, and for example, I don't think it makes sense for personal vehicles like cars. OP started a though experiment where we think of a new technology chain where energy is abundant and irregular. In this setup hydrogen might make sense because its energy intensive process is no longer an issue.
- pkphilip 5y ago
  I am not sure why any talk about Hydrogen triggers such a visceral reaction from people. There has been major advances in Hydrogen research as well - from production to storage. Both of have gotten much cheaper (consider UNSW's research on using Nickel instead of Platinum electrodes).
morpheos137 5y ago
what is "hydrogen based kerosene?" I understand normal kerosene is almsot 100% hydrogen and carbon. How does hydrogen basing kerosene remove or reduce the carbon while still yielding an energy dense liquid at STP?
- foerbert 5y ago
  They said carbon neutral, so I'm assuming the idea would be to use carbon dioxide and hydrogen to make kerosene to begin with. Then you can burn it and get the carbon dioxide back to start over. It's not carbon from the process entirely, but instead simply not adding additional carbon dioxide to the atmosphere.
  - morpheos137 5y ago
    ok. I see. Due to conservation of energy it takes energy to synthesize fuel hydrocarbons. So you might start with carbon dioxide, run it through some energy consuming process exposed to hydrogen and get hydrocarbons and water as the byproduct from the excess oxygen. I don't know enough chemistry to know what the exact synthesis method would be but I do know it would require substantial energy input. Thus the kerosene serves as a kind of battery. It is not a primary energy source any more. If this is feasible why not make carbon-neutral gasoline too?
    - frosted-flakes 5y ago
      Too much energy loss. For airplanes it might still be worthwhile because the weight-savings are so subatantial.
    - wiml 5y ago
      Yes, exactly. There are/have been various small scale projects along those lines. Hydrogen and CO2 to methane, to longer-chain hydrocarbons that can be put into existing engines. As you say, the synthetic fuel is just an energy (and carbon) carrier, you have to put all of that energy into the system somewhere — ideally from solar or wind or nukes or something.
    - 5y ago

by Adrig 5y ago

Hydrogen could be interesting as energy storage in this configuration. And hydrogen-based kerosene would make airplanes carbon-neutral but is really energy intensive

seb1204 5y ago

No it is not. Stop the straw man argument. Hydrogen has been talked about 10 years ago and the technology is still in its beginnings compared to most solar components nowadays. Hydrogen is also increasingly used by the fissile/carbon industry as a decoy to keep their gas on longer to make hydrogen.

iamthemonster 5y ago
"Hydrogen" is a fundamentally different thing to "solar". There is no "straw man argument" being made because it's comparing apples and pears. The only purpose of hydrogen is to make energy in one point in space & time and then use it in another point of your choice without CO2 emissions. Solar is to convert sunlight to electrical energy, but you don't get to control when the sun is shining. The technology to generate hydrogen is also completely mature and has been since before I was born, whether we are talking steam methane reforming or electrolysis. It's just not very cheap.
- smegger001 5y ago
  except hydrogen is a horrible option. It is hard to store safely, it is highly explosive, energy expensive to produce vs the energy you get back out, it damages its own holding vessels via hydrogen embitterment, outside of a few niche areas it in generally a bad option.
  - hef19898 5y ago
    No idea about energy consumption, so I would assume using dirt cheap solar in remote places with defacto zero variable production costs (over simplified, but this is one reason wind and solar are pricing out other sources on the German spot market which ignores fix costs) might change that. Long term storage of hydrogen is quite easy so. It can be stored in thermal oil, rendering it inert. In thay form it isn't even considered dangerous goods for transportation anymore. Source: I consulted a green hydrogen project on logistics a while ago.
  - labawi 5y ago
    > highly explosive It's only explosive when mixed with air in confined places, as is gasoline, LPG, CNG, steel, wood and flour. Unlike most others, confinement is a requirement, otherwise it escapes too quickly. See [1] for comparison. > hard to store safely, damages its own holding vessels For these reasons I suggest we should produce and store methane, though hydrogen issues aren't a showstopper and hydrogen fuel cells are more efficient. [1] https://hydrogen.wsu.edu/2017/03/17/so-just-how-dangerous-is-hydrogen-fuel/ https://hydrogen.wsu.edu/2017/03/17/so-just-how-dangerous-is...
    - makomk 5y ago
      Hydrogen is highly explosive at almost all concentrations in air, extremely easy to ignite, and leaks through most widely-used materials. It's much worse in all these aspects than common fuels like gasoline, LPG, natural gas, etc.
      - labawi 5y ago
        While the claims are (likely) technically true, if you are trying to insinuate it is less safe, then that is a false conclusion. As an example, many garages ban LPG cars, but don't care about CNG, AFAICT, because LPG can pool around on the bottom, but methane is light and easily escapes. Hydrogen is even lighter and harder to contain. The link [1] has compelling arguments.
  - pfdietz 5y ago
    > hard to store safely It's far easier to store it (underground, as compressed gas; this is a demonstrated technology) than it is to store energy in batteries. The cost/energy capacity can be extremely low, ~ $1/kWh equivalent.
    - smegger001 5y ago
      at that point we are no longer looking at a fuel for mobile vehicles and other technologies become better without the lossful need for electrolysis. pumped storage is highly effective for example.
      - pfdietz 5y ago
        Sure, but the cost per unit of energy storage capacity is also higher for PHES. So PHES (and batteries on one side, and hydrogen on the other) have different storage use cases. In general combining several storage technologies like these can end up being better than using just one.
  - lovemenot 5y ago
    If you can acquire hydrogen economically, it can be converted to ammonia cheaply. For many industrial processes, ammonia is a well-established common feedstock, having none of the issues of hydrogen you mention. Here in Japan, some Combined Cycle Gas Turbine plants are already running with 10% ammonia blend. I think you are right about pure hydrogen, but I can see green-hydrogen-into-ammonia as viable for many applications including heavy transportation (train, ship, truck). We just need much more economic electrolysis, because hydrogen is almost always produced from fossil fuels today.
    - nickik 5y ago
      I learned about this only 10 years ago and then it was to late already, but had they started to convert to Flex-Fuel Vehicle in the 90s it would have meant much cheaper fuel in the 2000s (because natural gas to methanol is cheap and gas was cheap). Plus you could easily replace it with solar produced methanol overtime. EV however killed the need for that for the most part. Today I don't really think synfuels have much of a application. Batteries and storing energy electrically will win. It will not be so long until you can basically do Iron-Silicon battery for a very cheap price. Or if we finally figure Sulfer we could have amazing batteries for super cheap.
- diordiderot 5y ago
  Hydrogen has very low energy density compared to gasoline. Like how diesel has more energy than gasoline. It also has a terrible efficiency. I think you lose ~70% from electrolysis. You also have the problem that most hydrogen today is made from petroleum!
  - kolinko 5y ago
    That matters for hydrogen cars, which are a terrible idea. But for grid storage energy density doesn't matter too much. Hydrogen, with all it's downsides, is awesome for long term storage because it scales sublinearly with capacity.
- pfdietz 5y ago
  > The technology to generate hydrogen is also completely mature That depends on what metric you are looking at. Efficiency? Perhaps. Cost/kW of the electrolyzer? Not true at all. Also, the use case for electrolyzers has changed: from converting relatively pricy baseload power to hydrogen to converting cheap intermittent power to hydrogen. For the latter you want to trade efficiency for lower capital cost.
frosted-flakes 5y ago
What straw man argument? You can refute claims made without resorting to such accusations.
ReptileMan 5y ago
The idea is to use hydrogen as easily scalable battery. All of the things that prevent fuel cells from being easily applicable in cars are not such a big factor in closed loop system.
Svoka 5y ago
Stop using "straw man" inappropriately. That's just not what it means.
Adrig 5y ago
I'm not sure you're familiar with straw man arguments. I know the drawbacks of hydrogen, and for example, I don't think it makes sense for personal vehicles like cars. OP started a though experiment where we think of a new technology chain where energy is abundant and irregular. In this setup hydrogen might make sense because its energy intensive process is no longer an issue.
pkphilip 5y ago
I am not sure why any talk about Hydrogen triggers such a visceral reaction from people. There has been major advances in Hydrogen research as well - from production to storage. Both of have gotten much cheaper (consider UNSW's research on using Nickel instead of Platinum electrodes).

morpheos137 5y ago

what is "hydrogen based kerosene?" I understand normal kerosene is almsot 100% hydrogen and carbon. How does hydrogen basing kerosene remove or reduce the carbon while still yielding an energy dense liquid at STP?

foerbert 5y ago
They said carbon neutral, so I'm assuming the idea would be to use carbon dioxide and hydrogen to make kerosene to begin with. Then you can burn it and get the carbon dioxide back to start over. It's not carbon from the process entirely, but instead simply not adding additional carbon dioxide to the atmosphere.
- morpheos137 5y ago
  ok. I see. Due to conservation of energy it takes energy to synthesize fuel hydrocarbons. So you might start with carbon dioxide, run it through some energy consuming process exposed to hydrogen and get hydrocarbons and water as the byproduct from the excess oxygen. I don't know enough chemistry to know what the exact synthesis method would be but I do know it would require substantial energy input. Thus the kerosene serves as a kind of battery. It is not a primary energy source any more. If this is feasible why not make carbon-neutral gasoline too?
  - frosted-flakes 5y ago
    Too much energy loss. For airplanes it might still be worthwhile because the weight-savings are so subatantial.
  - wiml 5y ago
    Yes, exactly. There are/have been various small scale projects along those lines. Hydrogen and CO2 to methane, to longer-chain hydrocarbons that can be put into existing engines. As you say, the synthetic fuel is just an energy (and carbon) carrier, you have to put all of that energy into the system somewhere — ideally from solar or wind or nukes or something.
  - 5y ago