pfdietz

47 ms·

961.
by pfdietz 8mo ago
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,
962.
by pfdietz 8mo ago
The reference I gave you completely disagrees with your statement. So, present a link justifying it or I will just go with the link I have.
963.
by pfdietz 8mo ago
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 se
964.
by pfdietz 8mo ago
I said expensive. Total cost is the relevant metric, not efficiency. https://docs.nrel.gov/docs/fy22osti/81662.pdf It's a common mistake to think efficiency dominates all other metrics. It's never ju
965.
by pfdietz 8mo ago
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 natu
966.
by pfdietz 8mo ago
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.
967.
by pfdietz 8mo ago
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 hyd
968.
by pfdietz 8mo ago
It would be moved by pipeline as a compressed gas, not as LH2. The US already has > 1000 miles of H2 pipelines.
969.
by pfdietz 8mo ago
> Carbon doesn't really contain all that much hydrogen. The hydrogen also comes from water reacted (mildly endothermically) with carbon, and by further reaction of carbon monoxide with water. C + H2O --> CO + H2 CO + H2O --> C
970.
by pfdietz 8mo ago
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 detra
971.
by pfdietz 8mo ago
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
972.
by pfdietz 9mo ago
Whole Language vs. Phonics, for example.
973.
by pfdietz 9mo ago
We should only accept life damaging educational malpractice from public schools.
974.
by pfdietz 9mo ago
On the other hand, 80 acres of PV could gross more than $2M/year.
975.
by pfdietz 9mo ago
Those images feel biblically accurate. Maybe add some pairs of wings, Claude.
976.
by pfdietz 9mo ago
It's helpful in justifying screening that non-small cell lung cancer treatments have greatly improved in recent years.
977.
by pfdietz 9mo ago
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
978.
by pfdietz 9mo ago
Insurance-based medical systems mean the patient has transferred responsibility for saying no to those actually paying the bills. They have to draw the line somewhere.
979.
by pfdietz 9mo ago
> I don't think LNT is accurate There's excellent reason to think LNT is accurate: at low doses, almost every cell is exposed to at most one radiation event. The dose affects how many cells experience a (single) event, but doe
980.
by pfdietz 9mo ago
"I'm ten times the agent you are, agent 8.6!"
981.
by pfdietz 9mo ago
A 10x employee creates enough bugs to keep 10 other employees busy.
982.
by pfdietz 9mo ago
I for one have always welcomed Roko's Basilisk.
983.
by pfdietz 9mo ago
Link is to a paper with the title "Socioeconomic roots of academic faculty". The paper with the submission title: https://www.nature.com/articles/s41467-025-67423-y https://www.biorxiv.org/con
984.
by pfdietz 9mo ago
Sure, but one still has a savings if one goes to heavier noble gas elements over the lighter ones. The noble gases are used because they don't contaminate spacecraft surfaces. About the only place I can think of in a plasma engine whe
985.
by pfdietz 9mo ago
Inert gas in welding isn't used to carry heat, it's used as shielding to prevent oxidation, nitridation, and ingress of hydrogen. In any case, the heat capacity of the noble gases are almost identical. What xenon might do is red
986.
by pfdietz 9mo ago
Does anyone use xenon for welding? Argon, yes, but xenon is five orders of magnitude less common in air.
987.
by pfdietz 9mo ago
Given that ~100 million tons of oxygen are produced annually, extracting all the xenon from that air would yield about 170 tons/year. So there's a bit of room for growth. The BepiColombo number is similar, I think, to the amount
988.
by pfdietz 9mo ago
I wonder how the albedo has changed, and evaporation of water there.
989.
by pfdietz 9mo ago
> Clay Christensen is smart Not anymore. He died in 2020.
990.
by pfdietz 9mo ago
> [xenon is] great for in-space propulsion because it’s fairly heavy (so you get more ooomph per atom) More specifically, for a given exhaust velocity and grid spacing, the space charge limited thrust density (thrust/area) of an ion

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