Hydrogen burning could have a place in an all-renewable grid: it could be much more economical for very long duration storage than using batteries. The last 5-10% of the grid becomes much cheaper to do with renewables if something like hydrogen (or other e-fuels) is available.
A competitor that might be even better is very long duration high temperature thermal storage, if capex minimization is the priority.
> it could be much more economical for very long duration storage than using batteries
Yes, but that's not the only option you have. With the absolutely awful efficiency of burning hydrogen you'd need to be building a massive amount of additional wind and solar - which in turn means you'll also have additional capacity available during cloudy wind-calm days, which means you'll need to burn substantially less hydrogen to generate power.
This leads to the irony that building the power-generation infrastructure for generating enough hydrogen means you won't even need to bother with the hydrogen part: you're basically just building enough solar that their overcast supply is enough to meet the average demand. As a bonus, you've now got a massive oversupply during sunny winter days and even more during summer days, so most of the year electricity will essentially be free.
Efficiency is not very important for very long duration storage. What's important is minimizing cost, which is dominated by capex, not by the cost of the energy used to charge the storage system. Paying more to charge it can make sense if that greatly reduces capex.
A BTU of hydrogen requires more energy to compress to a given pressure than a BTU of natural gas, but hydrogen also has lower viscosity, so less recompression is needed. The point you raise does not rule out hydrogen pipelines.
If it does, then it also rules out long distance transmission of electrical power, as that is even more expensive. And the hydrogen advantage is even greater when one considers one can piggyback storage onto this system, as is done in natural gas pipelines. The electrical system would need additional batteries which are much more expensive per unit of storage capacity.
The PDF you shared actually agrees with my point if you care you to read it. It models the cost for a specific HVDC implementation, but the HVDC line selected is more expensive when transporting just 3% of the energy of the pipeline.
The same capex and opex can support 100x more Wh-km via HVDC, making HVDC at least an order of magnitude cheaper then the H2 pipeline.
What's interesting to me is that this is completely uncontroversial and incontrovertible, so I wonder where your insistence otherwise is?
I'm sorry but you appear to be completely deranged. The paper says nothing of the sort. Let me give the abstract:
"This paper compares the relative cost of long-distance, large-scale energy transmission by electricity, gaseous, and liquid carriers (e-fuels). The results indicate that the cost of electrical transmission per delivered MWh can be up to eight times higher than for hydrogen pipelines, about eleven times higher than for natural gas pipelines, and twenty to fifty times higher than for liquid fuels pipelines. These differences generally hold for shorter distances as well. The higher cost of electrical transmission is primarily because of lower carrying capacity (MW per line) of electrical transmission lines compared to the energy carrying capacity of the pipelines for gaseous and liquid fuels. The differences in the cost of transmission are important but often unrecognized and should be considered as a significant cost component in the analysis of various renewable energy production, distribution, and utilization scenarios."
I'm to read this as supporting your assertion that electrical transmission is several times cheaper??
In fairness, hydrogen from gas would enable the CO2 to be sequestered. If the vehicle itself burned the natural gas that would require recapturing the CO2 from the atmosphere itself, which is much more challenging.
None of this is to detract from the attractiveness of battery vehicles.
Carbon sequestration is another of those "if we did this, it might solve the problem, but there's no serious move to do it and pay for it on the scale required, plus it's prone to cheating".
Storage is the bigger problem, specifically very long duration or rarely used storage (to cover Dunkelflauten, for example) for which batteries are poorly suited. Hydrogen (or more generally e-fuels) is one way to do that, but another very attractive one is very low capex thermal storage. Personally, I feel the latter would beat hydrogen: the round trip efficiency is similar or better, the complexity is very low, power-related capex should be lower, and there's no need for possibly locally unavailable geology (salt formations) for hydrogen storage.
With this sort of storage, Alaska in winter gets its energy from Alaska in summer.
I much prefer tests with low false positive rates.
I recently had such a cancer-related test. A cousin had a BRCA2 mutation and I was concerned I could have it also. Insurance would not pay for the testing, but one can get a panel of such genetic tests for just $250 now, so I went ahead. And it was negative. This is reassuring not just to me, but also to my children, and (somewhat) my sibling (the relevant parent is no longer alive).
Had this test been positive, the chance of pancreatic cancer would have gone way up, so frequent scans (I think annual MRI and ultrasound?) would have been justified.
A competitor that might be even better is very long duration high temperature thermal storage, if capex minimization is the priority.
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