186/ "If a current of 1 ampere flowing through a coil produces flux linkage of 1 weber, that coil has a self-inductance of 1 henry."

185/ but doctor ...

good post on this phenomenon from the point of view of a very influential software engineer who is also a big LLM user

If I'm talking to a credible technical founder with real expertise and a granular TEA I expect (and regularly receive) a full levelized cost breakdown which drills down into both OPEX and CAPEX contributions. plenty of startups do this math and do it well.

this press release does not do it well.

it's not physically impossible but it requires energy to be next-to-free, on top of extremely cheap carbon capture and C1 upconversion/blending, all at near-perfect efficiencies, and low CAPEX for each unit operation.

that it doesn't violate the laws of thermodynamics is a very low bar, indeed.

non-green premium SAF is a maybe for biofuels (HEFA, maybe AtJ) — but watch for iLUC emissions, food vs. fuel, scalability caps. bio residues should be valorized and there are competing use cases, but on a calorific basis SAF isn't the worst.

eSAF (PtL) w/o green premiums is at least a decade off.

PS: Rob, if you end up reading this, the data that would change my mind are bulk galvanostatic traces of your eCDR catalyst with overlaid FE% selectivity over long timescales — ideally 10,000+ hrs but I doubt you even maintain performance for 100s. Will sign NDA, email is [email protected] (:

I hate to defend F-T but it's used in efuels because it works AT SCALE, i.e. decades of performance at high throughput. There is a reason they admit their method is not certified!

I'll close by saying that this Tech Review article basically still holds up. www.technologyreview.com/2022/04/25/1...

Rob McGinnis linked some ACIE paper like it was technical proof but even with free electricity and CO2 the catalyst costs alone would have to be something like <<$1 / m2 (of nanostructured Cu@C!) to break even with generous assumptions of catalyst lifetime.

the last time i diligenced these guys (~2022, granted) their catalyst was something like "copper nanostructures deposited on carbon nanospikes", (cf. link related). These catalysts are expensive, fragile, and even they only get ~100s of mA/cm2 and ~50% FE.

onlinelibrary.wiley.com/doi/abs/10.1...

notice the things they don't say in this announcement: what their catalyst is, what it costs, what their reaction rate is at STP (current density / selectivity), what their catalyst lifetime is. their system is aqueous, so they're on a knife-edge with parasitic HER balancing current density and FE%.

if your technoeconomics rely on 1¢/kWh solar that's already a bad sign. the claim is they have a low-T, low-P system suitable for intermittent operation. even if you accept this, low c.f. is a multiplier on your base CAPEX (if your reactor is only running 20% of the time, payoff time is 5x longer).

flattered you thought of me. my comment:

there are great companies in the efuel space and Prometheus is not one of them. if they try to scale this to a continuous reactor they will fail. that their 'technical validation' is an FTIR & GC trace should be proof enough that they are not serious people.

funny story, the ~2008 shale boom + US becoming the biggest gas producer happened to coincide with a global acceleration in atmospheric methane levels.

also turns out that O&G methane leaks were self-reported and systematically underestimated. probably just a coincidence!

cc @kevinjkircher.com

it's easy to conflate heating and cooling and forget that an air conditioner is a heat pump with a COP of 3~5. heating takes a lot of energy, but it's masked by the density of chemical fuels. if you try to replace gas heaters with straightforward Joule heaters at a COP of 1 you will have a bad time!

You need significantly more generation capacity without heat pumps, this is because heating is a high percentage of many nations energy consumption (along with road transport) and heat pumps are very efficient.

to be clear I am taking the piss, but if "ladders" makes the top 10 list of "most dangerous things in your chem lab" I am allowed to poke a little fun

the only way I could injure myself in an analytical chemistry lab would be to deliberately unchain and crush myself beneath a gas cylinder