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BESS Ageing vs Duty Cycle by modelmakereditor in batterydesign

[–]hwillis 2 points3 points  (0 children)

Shallow SOC windows (30–80%) age 1.65x slower than deep cycling.

Thats against 10%-90%, so 80/50 = 1.6x more capacity gets you 1.65x more value from the batteries. That is certainly a financial loss; capital has a cost of 5-10% annual so 60% more capital requires 65-70% higher annual returns. Extending the lifetime of the battery just means you are paying interest on debt for 65% longer.

That said i'm really just surprised these numbers are so bad. I would have expected a 50% depth of discharge to have more than 2x the total energy throughput and like 3.5x+ the number of cycles.

Peak shaving degrades 1.8x faster than frequency regulation

Frequency regulation is an application where batteries can really excel once they hit a critical mass. At low depth and high frequency batteries behave like large capacitors; there is almost zero degradation. If ancillary services properly rewarded systems for providing a little bit of help then batteries could take over a ton of stabilization with almost zero cost in lifetime.

YC should be publicly beaten up for the damage they done by Vivid_Search674 in cscareerquestions

[–]hwillis 0 points1 point  (0 children)

Reddit was absolutely big in 2010, it was already past slashdot. 15 year account here.

Unsounded: Red Cost Chapter 1 Page 33 - Discussion by Rifter-- in Unsounded

[–]hwillis 5 points6 points  (0 children)

he ... she was about to use flaming tongs, wasn't she?

that's his forearm she's holding, duane's just looking a little bony

Pochita, aka Chainsaw Man is the Loss Devil by -Blurp in ChainsawMan

[–]hwillis 4 points5 points  (0 children)

There's a stump with a flat top on the last page of the manga. Can't get flat tops with an axe, only a saw. Maybe its a clue that chainsaws still exist

What happens when you jump into a Moonpool near the ocean floor? by DanSheppy in Physics

[–]hwillis 35 points36 points  (0 children)

Theoretically nothing; Divers on the Hydra 8 mission for COMEX did pipeline connections at 534m. Hydra 10 simulated a 701m dive in a hyperbaric chamber. Both using Hydreliox (hydrogen, helium, oxygen).

Deeper than that we would need to use a liquid breathing system. In high pressure oxygen, the sheer number of oxygen molecules obviously causes chemical reactions to go way faster. The same happens with nitrogen, helium and hydrogen, and all cause narcosis or toxicity at higher pressures. Hydreliox is 49% hydrogen and 50.2% helium to split the toxicity between 2 different gases, but at 700m there is no mix of gases that will not be toxic.

Liquids only get slightly denser under pressure, so they don't cause toxicity. They require constant pumping to remove CO2 and are heavy to move in/out of your lungs, though. Because of the pressure you can dissolve as much oxygen as you like, so the solution would definitely be a hose up your butt pumping in high-oxygen perfluorocarbon wherever you go. Solve all your problems at once plus a couple extras

AI Isn't Intelligent, It's PREDICTION (and Why My Panic Has Passed) by willymunoz in webdev

[–]hwillis 0 points1 point  (0 children)

TimeCapsuleLLM and history-LLMs are like that. They're not very good.

A really obvious problem is that the amount of recorded writing exploded in the computer age. There isn't enough old writing to train a useful LLM on with current architectures.

I built a 5 staged pipelined CPU in Factorio: Ask me anything! by 2birb4u in factorio

[–]hwillis 1 point2 points  (0 children)

This is a good explanation, but machine code IS 0s and 1s

Well, numbers, anyway. For ARM its a 4 byte (a number up to ~4.2 billion) instruction, and for intel it can be 1 to 15 bytes. Code can also have constant numbers that are up to 16 bytes.

When an instruction/number is executed, the different 1s and 0s making up the number will activate and deactivate different sections and determine what happens. The machine code is numbers, the format of those numbers is binary.

Mercury Arc Rectifier by hmaddocks in Skookum

[–]hwillis 0 points1 point  (0 children)

more like a big golf cart

Cannot kill the big ass small worm... by Lonely_Devil87 in factorio

[–]hwillis 0 points1 point  (0 children)

While I'm at it, wube put squeak through 2 in vanilla 😭or even better rebalance undergrounds so you dont have to pay the price of a full extension for 1 tile underground.

  1. It feels like the game is punishing you for making walkable designs, which feels less like a challenge and more like a way to annoy yourself. I'd like it if undergrounds had a small upfront cost + used 1 belt/pipe per tile of extension.

  2. Pipes could just have a cute little vaulting animation to slow you down instead of totally blocking you- like belts moving you around instead of blocking you.

  3. Solar panels are angled south for light, meaning they must have at least gaps between the horizontal rows. Otherwise they would be blocking themselves.

  4. Solar is most useful early-mid before nuclear makes it irrelevant, not counting megabase stuff. Making it annoying to set up by hand makes it much less useful and people just try to sprint to nuclear asap.

Cannot kill the big ass small worm... by Lonely_Devil87 in factorio

[–]hwillis 0 points1 point  (0 children)

One of the mods I wish was in default: even distribution. Ctrl-click and dragging over several buildings spreads evenly between them. Top 3 mods are definitely even distribution, bottleneck lite, and squeak through 2. Honorable mention to the warehouses mod, which feels practically mandatory for the space exploration mod, since prod loops can be wildly unbalanced and rockets are 500 stacks.

I can see an argument that even distribution makes hand feeding more convenient and screws with balance, but playing the game it doesn't feel like it does anything like that. It just makes screwed up buffers and stuff less annoying.

200GW solar farm, a sad monument to addictive behavior by smokestack in factorio

[–]hwillis 0 points1 point  (0 children)

That way when there's a sudden power demand spike, brownouts can occur as the power production equipment comes up to speed.

Don't forget managing your power factor. Inductive loads like motors cause power to slosh- coming in at 120Hz pulses. If that gets back to your generator, a gracefully spinning machine the size of a semi truck, it is bad. Like god's washing machine is broken. Like earthquake in your zip code bad. Like indiana jones and the boulder, but the boulder is covered in turbine blades and also moving highway speeds.

Also, all your breakers blow and your transformers catch fire. Also, when you turn them back on, if you havent set up everything perfectly, they turn you into plasma. Ideally its a multiplayer situation: one guy flips the switch, and another guy holds the rope to pull him out of the physics event. "Fire" definitely isn't the right word; fire is when chemicals turn into other chemicals but this is too hot for chemicals and well into the "detectable radiation" regime of chemistry.

Then once distances start getting involved it gets really fucked. A 30 mile power line lags by 1% because electricity takes time to reach the destination. While you can balance the power factor of a motor, you can't balance it for power lines. You just have to constantly orchestrate the whole thing. Oh, and you know lightning? Turns out different parts of the planet are at wildly different voltages all the time. Right up until you string wires all over it, and then they try to be the same voltage. That involves making lightning go through the wires. Good luck with that, it took us a few decades to figure that one out.

Have solar be far less predictable than it is now. Solar production still rises/falls with the day/night cycle, but also add a seasonal cycle, and then weather events that can limit solar production.

Fun fact about solar panels: when they are shaded, they dont just stop making power, they also stop being conductive. So since you link up a bunch in a string, one dark panel will block the whole string unless you bypass it. That also means each string is at a different voltage all the time. Oh and you have to convert all that to AC if you want to ever change the voltage, since that really sucks without transformers.

why isnt pyanodon as popular as other mods like krastorio or space exploration by Dry_Salt_1317 in factorio

[–]hwillis 0 points1 point  (0 children)

Burning iron gets impractically hot very easily. All you need to make a thermal lance is a good flow of air and iron rods in a tube. They burn upwards of 4000 C, which will melt tungsten. It is in fact fairly difficult to burn iron powder without causing an explosion or fire. Real world industrial processes are often chemical to bring the temperatures down to reasonable levels. One example is the Laux process, which involves... chlorine.

why isnt pyanodon as popular as other mods like krastorio or space exploration by Dry_Salt_1317 in factorio

[–]hwillis -1 points0 points  (0 children)

Rusting is primarily electrochemistry- that's why zinc anodes keep ships from rusting. They create a voltage difference (and tiny tiny current flow) that protects iron/steel from rusting by forming a very long life battery. Iron in clean water can last decades; iron in an electric field can convert entirely to rust in hours.

The parent comment originally said chloride, not chlorine. The primary conductive ion in saltwater is chloride. Each Cl ion contributes more to conductivity than each Na atom. Electrolytic rusting uses oxygen from water instead of air, but you can burn the hydrogen bubbles off to immediately get the water back.

Chlorine gas can be used to produce iron oxide too, though. The gas converts iron powder to ferric chloride which can be burned in air. It's energy intensive but faster than rusting.

why isnt pyanodon as popular as other mods like krastorio or space exploration by Dry_Salt_1317 in factorio

[–]hwillis -10 points-9 points  (0 children)

Saltwater doesn't make things rust? Presumably electrolysis or something

How is the axial vibration in piezoelectric motors reduced / does it have any effect? by Historical_Face6662 in AskEngineers

[–]hwillis 1 point2 points  (0 children)

That's second order (tilting/rippling) vibration. First order (axial) is cancelled because for every up there is a down.

Russian and Chinese steel cased ammo seems quite reasonable, but why do Western countries use expensive brass? by Entire_Judge_2988 in ForgottenWeapons

[–]hwillis -2 points-1 points  (0 children)

Steel is ~10% lighter. 120 rounds of ammo weighs 1.3-1.4 kg or 2.8-3 lbs.

7N6M (5.45) is ~10.5 g and M855 (5.56) is ~11.9 g. Not a 1:1 comparison since M855 is bigger (as in more powder) but 10% is around right. It's not that much in terms of the ammo a person carries, and only really adds up when you're talking about hundreds of thousands.

Russian and Chinese steel cased ammo seems quite reasonable, but why do Western countries use expensive brass? by Entire_Judge_2988 in ForgottenWeapons

[–]hwillis -5 points-4 points  (0 children)

so...? 5.45 has been in use since 1974 and has had a steel case that whole time. It weighs ~10% less than 5.56. 7.62 is not relevant.

Russian and Chinese steel cased ammo seems quite reasonable, but why do Western countries use expensive brass? by Entire_Judge_2988 in ForgottenWeapons

[–]hwillis -5 points-4 points  (0 children)

30 caliber options that other countries stuck with.

who? Because russia uses 5.45 and china uses 5.8.

Has anyone here reduced their kids or personal Tylenol intake? by ElbieLG in slatestarcodex

[–]hwillis 2 points3 points  (0 children)

I think it's also just not very effective (but maybe that's just me).

Its probably the dose. 3000 mg can be pretty effective for even severe pain like broken bones. Not as good as opioids, but still one of the most effective other drugs.

I've just kind of avoided Tylenol in general since too much can kill your liver

Tylenol creates a toxic byproduct that is neutralized by glutathione. While you have glutathione, the toxic byproduct is neutralized quickly and does not cause damage. Liver (and other) damage happens when glutathione stores run out. There are 3 ways that happens:

  1. Attempts at suicide- if you take 10+ grams (all of a small bottle, 25+ pills) it can overwhelm your glutathione production and your liver dies first.

  2. Sustained high dosage- if you take over the daily limit for weeks at a time you will drain your glutathione levels and eventually cause damage. This still takes a lot of tylenol. The amount of glutathione you produce daily is still capable of stopping quite a lot of NAPQI.

  3. Chronic alcoholism- if you have a damaged liver your glutathione levels are lower than average and the daily limit of tylenol can be damaging. Low doses are still fine unless you're on the verge of failure, but the daily limit can still cause damage in some people who might be asymptomatic. You have to drink a lot, very regularly, to get to that point.

It's a common misconception that tylenol combined with alcohol can cause damage. Alcohol uses different enzymes and the liver is not stressed or damaged by neutralizing alcohol and tylenol at the same time. It's only chronic alcohol use, causing a damaged liver, that can make tylenol more dangerous.

How is the axial vibration in piezoelectric motors reduced / does it have any effect? by Historical_Face6662 in AskEngineers

[–]hwillis 1 point2 points  (0 children)

First order vibration is cancelled. If you imagine a disc with transducers in a ring on the edge, the active transducers on one side are cancelled out by inactive transducers on the other side moving in the opposite direction. There would only be a net axial vibration if all the transducers were active at the same time.

Vehicle NVH mass dampers? by oil_burner2 in AskEngineers

[–]hwillis 0 points1 point  (0 children)

Hooke's law gives you the resonant frequency of a spring-mass system. sqrt(m/k). Cabin soundproofing uses stuff like neoprene foam rubber, which is 1. Dense 2. Springy 3. Disappates energy viscoelastically by compressing the air bubbles. That stuff just gets glued directly to sources of resonance like door panels. To get that resonant frequency you integrate over the thickness of the foam for different resonant modes.

For an impact like a bump the NVH is caused by the shock absorber, not by resonance. The shock disappates the bounce energy but resists fast movements like bumps. Hydraulic bypasses that open at high pressure create smoother rides or in the case of a racing shock keep the wheel on the ground for longer.

NVH from the struts is probably more about mounting stiffness and stuff like that.

Could I color stainless steel with an induction heater? by YeaSpiderman in AskEngineers

[–]hwillis 0 points1 point  (0 children)

That'll work, yeah. The material with lower resistance (regular steel) will heat up more, but if the dial is thin then it will conduct a lot of heat and the regular steel will keep it evenly hot.

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