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kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

Factor in complete system requirements—cooling, casings, and safety systems—that 270 Wh/kg battery delivers only 170-180 Wh/kg of usable energy.

Jet fuel still maintains an 18-19× energy density advantage (3.2 kWh/kg vs. 0.17 kWh/kg) at the system level, which explains the fundamental range limitations we're seeing in electric aircraft development.

For VTOL applications specifically, it demands 2.5-3× more energy per mile than conventional flight, electric air taxi prototypes remain limited to 60-80 mile ranges—impressive engineering, but not yet practical for replacing most aviation applications.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

former engineer, but w/e.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

HSR infrastructure costs $50-80 million per kilometer in developed countries.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

At 10-15% conversion efficiency, you're burning 85-90% of your energy just making the damn fuel, requiring 6-7× more renewable infrastructure than direct electrification. Current production costs are $15-25/gallon (not the fairy tale $2-3/gallon of jet fuel), and the physics won't magically improve to hit their "3× oil prices by 2050" fantasy. To replace global aviation fuel would demand a staggering 32,000 TWh of new clean energy generation – that's roughly equivalent to building 900 nuclear plants just to make luxury jet fuel while the rest of the grid still burns coal.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

Density is a must have in our civilizations....

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

fair point, but most people don't open up chemistry books.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

impractical, the number of ships to install these things is already constrained, not to mention the dispatch, repair, and transmission costs.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

The energy required to extract, process and manufacture lithium batteries (70% of total lifecycle energy occurs before the vehicle moves) Grid transmission losses (5-8% average, up to 15% in extreme conditions) Battery charging/discharging efficiency losses The dramatic efficiency reductions in adverse conditions (33% range loss in cold weather)

For aircraft and marine applications specifically (which was my focus), the energy density problem (60x worse than jet fuel) creates cascading inefficiencies as you need more battery weight, which requires more energy to move, which requires more batteries, and so on.

Electric cars have different economics than aircraft/boats and can make more sense in certain contexts. But my analysis was specifically about why lithium propulsion for aircraft and marine vessels faces fundamental economic and physics challenges that can't be solved with current technology.

The tires on an electric vehicle wear down about 20% faster because of the load bearing of the battery weight.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

Sulfur Hexafluoride and Nitrogen Trifluoride proliferate under a CO2 minimization regime. Nobody is arguing with Arrhenius proofs.

Nitrogen trifluoride (NF3) is a potent greenhouse gas with a global warming potential (GWP) of 17,200 over a 100-year period, meaning it's 17,200 times more effective than carbon dioxide (CO2) in trapping heat in the atmosphere. This GWP value is used to calculate the CO2 equivalent of NF3 emissions.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

Yes.

kumarskion Electric Propulsion's Dirty Secret: Why Lithium Can't Fly (Or Float) Profitably

Fair point, check the post again, I've posted on twitter about the benchmark for productively profitable venture and PE dollars.

It's our taxpayer dollars at work.

As a public market pegged to the same grid constraints, I prefer $POWL over most of the private lithium companies being pitched.

kumarskion Why do transit agencies keep falling for the hydrogen bus myth?

https://www.slideshare.net/slideshow/the-hydrogen-myth-prese...

kumarskion Stereoretentive Cross-Coupling [pdf]

A new synthesis pathway....

Once in a blue moon or every decade....these folks wrangle differently...finding the bleeding edge that everyone overlooks.

kumarskion Can solar costs keep shrinking?

I think it's irrelevant if the cost of solar panels goes to zero, the reality is that the farm to fork cost/kwh is still quite high because dispatch and transmission are never cheap.

Furthermore, for every 1 pound of polysilicon produced...you get 4 pounds of silicon tetrachloride output.

I gambled on $UAN and $AMR guesstimating that the spread of renewables would lead to more nat gas and coal/steel consumption per a kilowatt hour produced globally. I got lucky and it worked out. I'm not bullish on solar costs going below the embodied energy cost of desal per 1000 gallons. (10-14kwh/1000 gallons)

kumarskion Show HN: Double – Design and invest in your own stock index

Been looking for something like this. Well done.

kumarskion Zilog Z80 CPU – Modern, free and open source silicon clone

Looks dope.

(I was on early efabless.com team) open source EDA.

kumarskion Mahbod Moghadam: An Obituary

I'm still torn up about this.

kumarskion Scientists Hit 301,000 Gbps Internet by Tapping New Fiber Wavelength Bands

thank you.

kumarskion Hacking into an insurance company by exploiting their premium calculator

India has bigger problems than data leakages.

Persistent power being one of these.

Can't wait til there's enough electricity in India to where hacks become a primary concern.

They're laying down 100k kilometesr of fiber optic per a month and 350 5g cell sites per day.

kumarskion Nvidia Trains LLM on Chip Design

https://motivo.ai

https://www.silimate.com/

https://www.astrus.ai

kumarskion Launch HN: Stellar Sleep (YC S23) – An app that helps people with insomnia

Godsend.

I imagine like 90% of HN'ers suffer from insomnia.

kumarskion Semiconducting Transport in LK99 reproduction attempt

My thoughts echoed. https://twitter.com/datarade/status/1685459221926547457?s=20

kumarskion Panel with photovoltaic material layered on silicon hits 33% efficiencies

When the sun stops shining, natural gas peaking plants are the backup.

kumarskion Panel with photovoltaic material layered on silicon hits 33% efficiencies

https://www.sciencedirect.com/topics/earth-and-planetary-sci....

kumarskion Panel with photovoltaic material layered on silicon hits 33% efficiencies

For every 1 pound of polysilicon generated, you create 2-4 pounds of silicon tetrachloride. Even if the cost of a panel goes to zero, it makes no difference because the costs to dispatch and transmission energy exceed the useful capacity of solar in a large % of areas where it is deployed on the grid and the specific times in the grid, you end up consuming more nat gas per kwh than if you'd just burned nat gas from start to finish.

I bought $UAN at $7-$9 and I'll continue buying between $75-$85. It's sort of a long call on natural gas - and for me a long call on ESG ridiculousness proliferating quickly.

The nat gas bull run will rise again with the wide scale institutionally backed ESG funds that get pointed toward solar deployments.

kumarskion SEC Sues Binance and CEO Zhao for Breaking US Securities Rules

Earlier today, I talked to people who are reformed criminals who have been thrown in Jail by the SEC and know its inner workings fairly well.

He'll likely get a slap on the wrist with some fines.

Doesn't look like anybody is going to jail.

We shall see how things shake out. Would get intriguing if the jaws of FINCEN suddenly opened up.

kumarskion Databricks Releases 15K Record Training Corpus for Instruction Tuning LLMs

Amazing.

Love databricks.

kumarskion Launch HN: Type (YC W23) – AI-powered document editor

I feel as if there's 100+ of these splattered across daily deals software sites and betalist.com.

kumarskion Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

"every MWh of renewable electricity put onto the grid would displace ~3MWh of fossil fuels being burned to supply grid electricity and eliminate over a tonne of CO2 emissions." - https://johnmenadue.com/the-green-hydrogen-myth/

Electric arc furnaces are rife with issues.

All the ESG "let's minimize CO2 emissions" stuff had me going long levered on nat gas.

https://bit.ly/kumarngbull

Have a look at $UAN, $FCG, and $TELL(Gamble) -- I went long levered in 2019 onwards.

If I have to watch the train wreck, I deserve to be compensated accordingly.

Steel data: https://twitter.com/datarade/status/1642716122343526400?s=20

To those who doubt my line of thinking:

Is there as ingle commercial steel plant that minimizes iron ores via hydrogen? Furthermore, we know that most of the hydrogen is produced by nat gas reformation.

To make zero carbon iron you'd have to do mass scale electrolysis and it would need to be powered by renewables, right?

https://www.industrytransition.org/green-steel-tracker/ - here's some 50+ green steel projects tracked, I check it periodically.

Cheers.

I do believe electric arc furnaces will get ESG ayatollah money and will scale over time even if counterproductive to basic scientific production metrics against feedstock requirements, throughput, quality, and industrial requirements.

kumarskion CFTC sues Binance and CEO Changpeng Zhao [pdf]

The full force of the federal gov't is coming for CZ.

I spoke with several people who work at various AGs and folks in DC.

It seems they will come down hard on him for a variety of reasons and through a variety of methods.