also ignoring that natanz was actually effectively airgapped, and was knowingly infected by another country's contractor's usb stick, working on behalf of dutch intelligence service
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the thing with using aluminum tape is that you can get away with very small thickness, because current flows only in top tens of micrometers depending on band. you can just roll up, say, 5cm wide, 0.5mm thick aluminum tape and have riveted/brazed/spot welded short length of 2mm thick bar to the ends for connecting capacitor. the problem is with mechanical stability of this setup, which is why you see pipes and thicker bars, bicycle rims etc, and here you would need some kind of horizontal bars for loop to more or less keep shape
with braid you get a lot of contacts between wires, and i'm not sure that resistance of them would be low unless tire is fully inflated. keep in mind that copper in contact with some grades of rubber develops copper sulfide film. maybe you can put short U-turn within loop at end opposite of capacitor and have adjustable shorting bar there. adjustable capacitor is more common by far, because if you can adjust it widely enough, you can get to different bands
if you're going for portable operation, wire dipole is probably the better way to go. cheaper, lighter, more efficient, you can roll it up and fit in your pocket. if you're operating out of a car, you don't need to fold magloop just lay it flat in the trunk
"has potential" and "could" but never "is"
90% of drugs that enter clinical trials, fail them
"All day Astronomy" seems to be a weird place to take medical news from
i'd expect shield to fray and core to bend with arrangement like this. if you just slide piece of pipe (can be rectangular, or U-shaped) it should be more durable. you'd be surprised at voltages developing there, even with 4W online calculators suggest something in 1kV range. 100W is over 5kV (voltage scales as square root of power)
btw if you don't need it collapsible, consider using bicycle rim as loop, or some kind of wide aluminum tape, as it has much higher equivalent diameter than coax (less losses)
you can add in parallel small adjustable capacitor, made from two or maybe four coax cores with some kind of sliding conductive sleeve around them all (piece of copper pipe moved by screw) this way you should be able to tune to any channel within cb band
additionally, you made your loop suitable for higher power than was previously (magloops tend to be limited by voltage across capacitor). if you use coax with foam core, capacitance per mm will be lower still. for adjusting, you can get away with only clipping away shield with nail clippers
it's a type of heat engine. heat engines require temperature difference to work, and the lower it becomes, the less energy is there in the first place and a very fundamental limitation, that is carnot cycle efficiency, goes down very quickly. in practice, all heat exchangers have some thermal resistance, and the lower temperature gradient you can afford to use up on this, the bigger heat exchanger becomes, making low grade heat powerplants extremely big and expensive on top of barely generating any electricity
i don't think there's a lot of energy to be squeezed from daily variations in air temperature vs lake temperature, you'd be better off just by using solar panels on the same area
take any aluminum can, cut it open, cut a plate fitting in your wallet, insert it there so that it sits on external surface if your walket, done, that's your yeehaw rfid blocking sleeve, extra mass 1g
if you want to scan bus pass you can put that card on external side of it
Because now you have to establish a complex supply chain and potentially large worker base in a place that’s potentially quite inconvenient for both, instead of a much simpler supply chain and smaller workforce.
i'm not sure why you think that it is the case. if you want to make aluminum, you just need a ship to come in and pile up alumina, then take up piled up aluminum. the process is decently automated these days and you avoid making hydrogen. if you want to make ammonia, then all you need is hydrogen that you use as soon as it's made and nitrogen which is separated from air on demand. nitrogen fertilizers account for something like 2% of global primary energy use so it's probably decently scalable. then you can ship out liquid pressurized ammonia, or convert it to ammonium nitrate which again you can pile up. however with methanol you run into a Problem, because you need carbon dioxide, which means that you have to ship it from somewhere or capture in a massive installation. this immediately makes logistics of this entire enterprise harder. if you want to convert methanol to hydrocarbons then it takes some extra energy for little benefit (2x energy density) and some losses. to some degree, maybe it will make sense, but maybe it'll be easier to just build up renewables where people already live
in that scenario biofuels get to serve much smaller segment than today in the first place so maybe it's less of a problem. there are also things like biogas
I strongly feel that hydrogen is even more of a dead-end technology than these e-fuels. It is a right pain to store and transport and has rubbish energy density. There’s no future in the hydrogen economy. I’d bet we’re more likely to jump to artificial photosynthesis and fancy fuel cells than we are to see any substantial hydrogen infrastructure.
and you base that on what exactly other than vibes? there are applications where you need hydrogen directly as a reagent like ammonia synthesis, and these are probably most adaptable to this approach. methane is also proper PITA in terms of storage, yet we store it anyway because it's cheap as a fuel. if hydrogen is cheaper than that, then it will be used where applicable. it's easier to transport coal than electricity but not lignite; i don't know how it will play out with hydrogen, but either way you can imagine a situation where hydrogen is generated onsite, or within pipeline distance, and used immediately or maybe with some storage worth hours to days. this fits iron smelting (DRI) nicely, today the fuel used for it is methane because it's cheapest (process common in India). if hydrogen is cheaper than that, it will be used instead. other than that, applications where high heat is needed and where no electric heating can be used would be another use of hydrogen, like glassmaking and metal objects manufacture. hydrogen might be not disastrously bad option as fuel for transportation, because every step in manufacturing other fuels introduces losses; there are other tradeoffs
what do you want to fuel these fuel cells with? hydrogen is simplest option and most efficient (60% roundtrip efficiency or so). artificial photosynthesis is not a thing currently and strictly worse than combination of any energy source + conventional electrolyzer, because you have to combine not within single device but within single material something that will work as both. this also is only applicable to solar, not to wind or nuclear. some of these direct light to hydrogen schemes also only use UV only, and hydrogen is mixed with oxygen which is suboptimal, not to mention that main output of that work seems to be grant applications, while both electrolyzers and solar panels or wind turbines are available today, in bulk, straight from factory, and even more efficiently in decarbonization terms, these can replace coal-based electricity generation
regardless, main value of electrofuels today is in propaganda
regular process starting from gas has carbon dioxide as a byproduct, so urea is another option, but with hydrogen it would have to be provided. it's more expensive even today. maybe liquefied gas carrier could provide carbon dioxide and load ammonia on return leg, with some other dry cargo ship picking up that urea at some other time
ftx also did something like that, but didn't release ad with matt damon
it's like the time when some crypto exchange bought ads on one stadium for years in advance and then went under
from bsky photos looks like entire gathering was 30 people. t h i r t y p e o p l e i might have counted some reporter or someone passing by randomly by accident
i think that business logic goes against your first point. spatially: if you have source of cheap energy and want to make money out of it, instead of making little money (by making fuel) why not make more money? (by setting there energy intensive manufacture) this seems to be current meta, with places like iceland and norway making aluminum and nitrogen fertilizers respectively. this can continue in other places and maybe extended to some other industries.
temporally (because there are also sunny and windy days when regular people won't consume all energy): this scheme requires cheap electricity, which is needed for cheap hydrogen. this requires massive renewables buildout, which means electricity is cheap for regular people, which means that every gas stove/heater and car will get replaced with electric ones, both residential and maybe perhaps faster for industrial users (more available loans). this means you have to reinforce transmission grid anyway. this also means cheap hydrogen, and because main input to its production is electricity, it makes more sense to use electricity when it's cheap. this means it's naturally suited to suck up all excess generation (both daily and seasonal), and also if electricity production is seasonal then so should be price of hydrogen. if price of electricity or hydrogen varies, then some industries can suck it up at greater rates when it's cheap. i'm thinking here of aluminum smelting (electricity input, daily variation, already done), or ammonia synthesis, or direct reduced iron smelting. i bet there's more. the point is, maybe you get to avoid storing hydrogen to some degree, because you can effectively store energy in finished or semi-finished goods. you can, for example, make some direct reduced iron and just store it when hydrogen is available, and then smelt it into steel in arc furnace when it's not. fertilizers are already sold in annual cycle and stored long term, and anyway ammonia is much easier to store than hydrogen. how it plays out will depend on energy/hydrogen costs vs storage costs vs capex for overcapacity costs. all together, i think this means that because of large amount of generation needed, you don't actually need to store energy this way at all, because when generation is low then electrolyzers turn off, and something will work at all times, probably. when you're able to do that, you won't need to
in terms of scale, first your lunch is eaten by EVs of various shapes, then by use of hydrogen for transportation (rocketry fits there), then you have to compete with biofuels (jet engine will take anything that burns without ash and can be pumped). then some of methanol will be used for fuel first, because it just works in engines and fuel cells, and it's a step before hydrocarbon synthesis. only then synthetic petroleum makes sense, this basically leaves some aviation (that won't use methanol) and military uses
drones can be also shot down and operators radiolocated very quickly
no, because they have separate comms using completely different bands. esp when you're talking about military
if you switch to different band, probably nonstandard and unlicensed, then there must be someone else to listen
not everybody heard of gas town within first two weeks
i don't know if they started it. what i suspect as their contribution is bold claim that electrofuels might be cheaper than regular petrol in the glorious future, while currently they're much more expensive. (30x?) strict prerequisite for their competitiveness is cheap electricity, but at this point they're not needed. there was also Porsche owned wind power to methanol plant, and while methanol works as petrol replacement, all the plastics in contact with it must be resistant which is not a given. i guess the main value of it for them is propaganda, they're not ready for EV manufacture
the point is, as always, to continue doing business as usual (in this case, by inhibiting BEV adoption). that fuel is carbon-neutral but also extraordinarily wasteful. trump's deal is something called "clean coal", which isn't (it suggests carbon capture, but it's not a thing, they marketed normal emissions control like we have in europe as some unusually green innovation). i think he was also captured by gulf monarchies for the one hour when their representative talked to him
e: wait it still makes smog so checks out
recently learned about electrofuels. it's a hypothetical rube goldberg scheme where you put enough energy to propel 5-7 EVs in, and pull out enough gasoline to fuel one car. it's sold as a green technology, because now gasoline is green somehow. this spin ignores that it would require massive buildout of renewables + nuclear, and just by doing this electrification of many energy end uses just makes sense, including transportation. (what the fuck is train??) it's also sold as a long term storage for renewables, but i struggle to see how scheme that has less than 30% roundtrip efficiency can be considered "storage". just build more renewables and don't use them all if needed
it's a complicated pr campaign by volkswagen group (and some other usual suspects). this is a nonexistent magic solution to a real problem, so it fits a common pattern (and also makes it stubsack material) that also attempts to shank electric vehicles adoption.
if anything, it's backwards because EVs are adopted faster than renewables buildout happens (cars last less than powerplants). if realized, this allows volkswagen group to manufacture regular cars for a long, long time even after oil refining stops. originally, it was proposed as a hypothetical luxury product for antique car owners, because it's physically possible, but doesn't make sense in energy or cost terms. but then someone spun it into potential regular retail good, and also maybe this pr campaign was a part of reason why internal combustion car ban was axed at eu level recently. now that it happened, they don't need to push it so hard
it is something ironic in there that last time this process made sense was in nazi germany, just this time source of syngas is different
i thought they were yet another rationalist offshoot
he's either out of fucks, or knows exactly what he's doing