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Hydrogen is not economical for most use cases. For example if you have solar/wind energy, you can transfer it very efficiently over existing power grid to prov

by kjksf 8y ago

Hydrogen is not economical for most use cases. For example if you have solar/wind energy, you can transfer it very efficiently over existing power grid to provide energy for heating or lights. Transmission losses in power lines are 8-15% so the efficiency is 85%+ (https://blog.schneider-electric.com/energy-management-energy-efficiency/2013/03/25/how-big-are-power-line-losses/ https://blog.schneider-electric.com/energy-management-energy...) If you do the same via hydrogen, you have to convert solar energy into hydrogen. That conversion is only 16% efficient i.e. you loose 84% of solar energy (https://www.nrel.gov/news/press/2017/1117-nrel-establishes-world-record-for-solar-hydrogen-production.html https://www.nrel.gov/news/press/2017/1117-nrel-establishes-w...). Then you have to transport the hydrogen from where it's made to where it's used. That's additional expense and efficiency loss. Then you have to convert hydrogen back into energy. Additional loss of efficiency. It just doesn't make sense economically (https://phys.org/news/2006-12-hydrogen-economy-doesnt.html https://phys.org/news/2006-12-hydrogen-economy-doesnt.html). Hydrogen is not an electricity source. It doesn't compete with solar or wind. It's electricity storage. It competes with batteries and it's not winning there either because of much greater efficiency losses and the fact that you would have to build (expensive) infrastructure (think network of gas stations, except for hydrogen).

exabrial 8y ago
Great points, but don't lose the trees in the forest: This isn't about efficiency, it's about convenience. Fueling a car for 400miles in 2m is acceptable at 16% efficiency if the energy wasted is "free". That's not possible with battery technology.
- TeMPOraL 8y ago
  It's possible if you allow for battery swapping.
  - exabrial 8y ago
    I think that'd be cool! The problem is batteries are worth so much $ the accountants get a little uppity when we stay exchanging a warranty part that costs $8k
jayalpha 8y ago
"Hydrogen is not economical for most use cases." Oh, wow. "For example if you have solar/wind energy, you can transfer it very efficiently over existing power grid to provide energy for heating or lights." This is correct. And the wind energy created at night you can just store. Somewhere. But where? "If you do the same via hydrogen, you have to convert solar energy into hydrogen. " You can also use wind energy or whatever energy to create H2. H2 has the advantage, that you can both, store energy in it and transport it. https://en.wikipedia.org/wiki/Regenerative_fuel_cell https://en.wikipedia.org/wiki/Regenerative_fuel_cell "Then you have to transport the hydrogen from where it's made to where it's used." In the worst case you just mix it into the natural gas pipeline. Worried about diffusion losses? They are lower than you think. "That's additional expense and efficiency loss." The expense is low because the gas pipelines already exists. The efficiency loss is not very high. "Then you have to convert hydrogen back into energy. Additional loss of efficiency." You can just burn hydrogen together with natural gas. It just doesn't make sense economically (https://phys.org/news/2006-12-hydrogen-economy-doesnt.html https://phys.org/news/2006-12-hydrogen-economy-doesnt.html). Quote from the article: “More energy is needed to isolate hydrogen from natural compounds than can ever be recovered from its use,” Bossel explains to PhysOrg.com. Yeah, right. This is not the case with any other energy storage available. Wait a second.... "Therefore, making the new chemical energy carrier form natural gas would not make sense, as it would increase the gas consumption and the emission of CO2." If it is created from renewable energy as an energy storage, then this statement is wrong. Be advised that hydrogen is also needed for methanol fuel: https://en.wikipedia.org/wiki/Methanol_fuel https://en.wikipedia.org/wiki/Methanol_fuel Instead, the dwindling fossil fuel reserves must be replaced by energy from renewable sources.” "Hydrogen is not an electricity source. It doesn't compete with solar or wind. I stop reading here. Batteries are not an electricity source, they don't compete with solar or wind.

by kjksf 8y ago

exabrial 8y ago

Great points, but don't lose the trees in the forest: This isn't about efficiency, it's about convenience. Fueling a car for 400miles in 2m is acceptable at 16% efficiency if the energy wasted is "free". That's not possible with battery technology.

TeMPOraL 8y ago
It's possible if you allow for battery swapping.
- exabrial 8y ago
  I think that'd be cool! The problem is batteries are worth so much $ the accountants get a little uppity when we stay exchanging a warranty part that costs $8k

jayalpha 8y ago

"Hydrogen is not economical for most use cases." Oh, wow. "For example if you have solar/wind energy, you can transfer it very efficiently over existing power grid to provide energy for heating or lights." This is correct. And the wind energy created at night you can just store. Somewhere. But where? "If you do the same via hydrogen, you have to convert solar energy into hydrogen. " You can also use wind energy or whatever energy to create H2. H2 has the advantage, that you can both, store energy in it and transport it. https://en.wikipedia.org/wiki/Regenerative_fuel_cell https://en.wikipedia.org/wiki/Regenerative_fuel_cell "Then you have to transport the hydrogen from where it's made to where it's used." In the worst case you just mix it into the natural gas pipeline. Worried about diffusion losses? They are lower than you think. "That's additional expense and efficiency loss." The expense is low because the gas pipelines already exists. The efficiency loss is not very high. "Then you have to convert hydrogen back into energy. Additional loss of efficiency." You can just burn hydrogen together with natural gas. It just doesn't make sense economically (https://phys.org/news/2006-12-hydrogen-economy-doesnt.html https://phys.org/news/2006-12-hydrogen-economy-doesnt.html). Quote from the article: “More energy is needed to isolate hydrogen from natural compounds than can ever be recovered from its use,” Bossel explains to PhysOrg.com. Yeah, right. This is not the case with any other energy storage available. Wait a second.... "Therefore, making the new chemical energy carrier form natural gas would not make sense, as it would increase the gas consumption and the emission of CO2." If it is created from renewable energy as an energy storage, then this statement is wrong. Be advised that hydrogen is also needed for methanol fuel: https://en.wikipedia.org/wiki/Methanol_fuel https://en.wikipedia.org/wiki/Methanol_fuel Instead, the dwindling fossil fuel reserves must be replaced by energy from renewable sources.” "Hydrogen is not an electricity source. It doesn't compete with solar or wind. I stop reading here. Batteries are not an electricity source, they don't compete with solar or wind.