4 ms·

> The correct figure to look at is wholesale price, which is often below $.03/kWh in US power markets, and lower at off peak times when one would make hydrogen.

> The correct figure to look at is wholesale price, which is often below $.03/kWh in US power markets, and lower at off peak times when one would make hydrogen. Again, the estimates shared in the study are made with the assumption that electricity used for hydrogen production is free. This is why I am left with the impression that you think the energy used for electrolysis amounts to a large portion of the cost of hydrogen storage. Because you seem to be fixated on the cost of electricity, even though hydrogen storage is still incredibly expensive even if electricity is 100% free. No, hydrogen does not have low cost of energy storage. Average estimates place the cost at $1,400 per KWh per year for average estimates and $800 per KWh per year for optimistic estimates. And for the third time, just to make sure that this fact gets across, these estimates are made with the assumption that the electricity supplied to generate hydrogen is at zero cost from surplus renewable generation. This cost needs to be recovered from people drawing the stored energy. If all this energy is being drawn in one day of the year, it's going to cost $1,400 or $800 per kilowatt hour depending of whether you use the average or optimistic estimates. If you draw the energy on 10 days out of the year then it's going to cost $140 or $80 per KWh. How does this make it more suitable for long term storage? It doesn't. Even if the cost were spread out over the entirety of the year it would cost anywhere from 60 to 120 times as much as the wholesale price of $0.03 per KWh. If this energy is only going to be draw on for part of the year this cost increase is going to be even larger because the same cost of storage needs to be recuperated from a shorter period of sales. It's the most suitable solution for long term storage by virtue of the fact that it's one of the only mechanisms we have for long term storage with our current technology. It's nowhere near cost effective. The costs are the total opposite of "so damn low".

pfdietz 6y ago
Sigh. You are just not connecting the dots. Yes, the cost to store hydrogen for LONG TERM STORAGE is higher than the cost to store electricity in batteries for SHORT TERM STORAGE. But the cost to store hydrogen for long term storage is LOWER than the cost to store electricity in batteries for the long term. If you are comparing batteries short term with hydrogen long term, you are comparing apples and oranges. Your study does NOT say batteries are cheaper than hydrogen for long term storage. They could not possibly be cheaper for that, since there are too few charge/discharge cycles to amortize the batteries' very high cost per kWh of capacity. You seem to be saying "just use short term storage!". But that's not a legitimate approach, since there are long term variations in supply and demand. Short term storage only applies to short term variations.
- manfredo 6y ago
  My reply was refuting your claim that hydrogen storage was cheap. Now you're going off on a tangent about short term vs. long term storage and ignoring the central point of my previous comment: the cost estimates for hydrogen storage are nowhere near cheap. > Yes, the cost to store hydrogen for LONG TERM STORAGE is higher than the cost to store electricity in batteries for SHORT TERM STORAGE. But the cost to store hydrogen for long term storage is LOWER than the cost to store electricity in batteries for the long term. > If you are comparing batteries short term with hydrogen long term, you are comparing apples and oranges. I'm not comparing anything. I'm providing a source on the cost of hydrogen storage, to refute your unsubstantiated claim that hydrogen storage is cheap. And as it turns out this cost is extremely expensive, regardless of whether it's used for short term or long term storage. > Your study does NOT say batteries are cheaper than hydrogen for long term storage. They could not possibly be cheaper for that, since there are too few charge/discharge cycles to amortize the batteries' very high cost per kWh of capacity. Correct, this study is about the cost of hydrogen not a comparison versus batteries. And for the second time, nowhere did I compare hydrogen against batteries. My reply doesn't even mention batteries once. All I used this study for was tho find an estimate for the cost of hydrogen storage. And that cost is $1,400 per kilowatt hour per year for normal estimates and $800 per kilowatt hour per year for optimistic estimates. This is incredibly expensive, contrary to your claim that the cost of hydrogen storage is "so damn low". > You seem to be saying "just use short term storage!". But that's not a legitimate approach, since there are long term variations in supply and demand. Short term storage only applies to short term variations. The point is that it's extremely expensive, and not a viable solution for any type of storage. Short term or long term. The cost per kilowatt hour of storage is just way too high to be viable. $800 per kilowatt hour per year for the optimistic estimates, and $1,400 for realistic estimates is insanely expensive. And again this is assuming that the electricity provided to convert water to hydrogen is free. In what world is $800 to $1,400 per kilowatt hour per year, "so damn cheap"? For hydrogen to achieve even just 1 day's worth of energy storage for the USA (11.5 TWh daily usage) at a cost of $800 per kilowatt hour per year would cost $9 trillion dollars per year. And remember, that's the optimistic estimate and assuming that the energy used to produce hydrogen is free. This isn't about short term vs long term storage. Hydrogen storage is incredibly expensive, it's not "so damn cheap".

pfdietz 6y ago

Sigh. You are just not connecting the dots. Yes, the cost to store hydrogen for LONG TERM STORAGE is higher than the cost to store electricity in batteries for SHORT TERM STORAGE. But the cost to store hydrogen for long term storage is LOWER than the cost to store electricity in batteries for the long term. If you are comparing batteries short term with hydrogen long term, you are comparing apples and oranges. Your study does NOT say batteries are cheaper than hydrogen for long term storage. They could not possibly be cheaper for that, since there are too few charge/discharge cycles to amortize the batteries' very high cost per kWh of capacity. You seem to be saying "just use short term storage!". But that's not a legitimate approach, since there are long term variations in supply and demand. Short term storage only applies to short term variations.

manfredo 6y ago
My reply was refuting your claim that hydrogen storage was cheap. Now you're going off on a tangent about short term vs. long term storage and ignoring the central point of my previous comment: the cost estimates for hydrogen storage are nowhere near cheap. > Yes, the cost to store hydrogen for LONG TERM STORAGE is higher than the cost to store electricity in batteries for SHORT TERM STORAGE. But the cost to store hydrogen for long term storage is LOWER than the cost to store electricity in batteries for the long term. > If you are comparing batteries short term with hydrogen long term, you are comparing apples and oranges. I'm not comparing anything. I'm providing a source on the cost of hydrogen storage, to refute your unsubstantiated claim that hydrogen storage is cheap. And as it turns out this cost is extremely expensive, regardless of whether it's used for short term or long term storage. > Your study does NOT say batteries are cheaper than hydrogen for long term storage. They could not possibly be cheaper for that, since there are too few charge/discharge cycles to amortize the batteries' very high cost per kWh of capacity. Correct, this study is about the cost of hydrogen not a comparison versus batteries. And for the second time, nowhere did I compare hydrogen against batteries. My reply doesn't even mention batteries once. All I used this study for was tho find an estimate for the cost of hydrogen storage. And that cost is $1,400 per kilowatt hour per year for normal estimates and $800 per kilowatt hour per year for optimistic estimates. This is incredibly expensive, contrary to your claim that the cost of hydrogen storage is "so damn low". > You seem to be saying "just use short term storage!". But that's not a legitimate approach, since there are long term variations in supply and demand. Short term storage only applies to short term variations. The point is that it's extremely expensive, and not a viable solution for any type of storage. Short term or long term. The cost per kilowatt hour of storage is just way too high to be viable. $800 per kilowatt hour per year for the optimistic estimates, and $1,400 for realistic estimates is insanely expensive. And again this is assuming that the electricity provided to convert water to hydrogen is free. In what world is $800 to $1,400 per kilowatt hour per year, "so damn cheap"? For hydrogen to achieve even just 1 day's worth of energy storage for the USA (11.5 TWh daily usage) at a cost of $800 per kilowatt hour per year would cost $9 trillion dollars per year. And remember, that's the optimistic estimate and assuming that the energy used to produce hydrogen is free. This isn't about short term vs long term storage. Hydrogen storage is incredibly expensive, it's not "so damn cheap".