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Comment Re:This is great but misplaced (Score 1) 41

First off, "normal car", please. 20% of all new cars sold worldwide are EVs now. Update your language to reflect the new reality.

Secondly, that's just not true. Towing a heavy trailer with a truck will see its MPG drop by like half. The rule of thumb is that every 100 pounds you have a truck tow drops its fuel economy by about 2%. 2500lbs = 50%. That's a very rough rule, but it gives a sense of what's normal.

Comment Re:Yay (Score 2) 41

You won't be "hanging out" - your car will be ready to leave before you are. By the time you go in, use the restroom, buy a drink or a snack, and get back to your car, you'll have already added the range you need to go to the next site.

Unless you need to get really full because you're in a charging desert (charging slows near the upper end), it basically is this way already, if you have a fast-charging EV and a powerful charger. And speeds just keep rising.

Comment Re:This is great but misplaced (Score 1) 41

You sure? Plugshare says Goffs has a 16kW NACS.

A Model 3, not towing anything (US ones don't come with a tow hitch, right?), arrive with 2%? I assume you're kidding. ABRP shows a 2024 Tesla Model 3 LR with 18" aero wheels leaving Barstow at 100% arrives at Needles at 55%. This is with seasonal weather enabled, and battery degradation of 5%. Switching to the SR, it arrives at 42%.

Let's see how bad conditions I have to choose to get it as low as you're saying. Let's try some random things.

SR: Going 10% over the speed limit. It's 50C (122F) - about 20F over the July average - and there's a 10 m/s wind (22 mph) - double the average - that the car is unlucky enough to be driving into head-on. That arrives with 1%

LR: Going 25% over the speed limit. It's 57C (135F) - as hot as the Death Valley record - and there's a 20 m/s wind (45 mph) - quadruple the average - that the car is again driving into head-on. That arrives with 4%.

Of course, if the SR just drops its speed to the speed limit it arrives with 10% remaining, and if the LR drops its speed to the speed limit, it arrives with a no-stress 27%. Even in these conditions. Both cars are, again, assumed to have 5% degradation.

So I'm not sure what you're talking about with your Model 3 claims. But I'll totally buy that towing something big and heavy will make that route non-viable. Towing dramatically increases vehicle energy consumption (not just EVs, either - all vehicles), like double the drain. Though I'm a bit surprised about jet skis being that much of an increase, as mentioned earlier.

Comment Re:This is great but misplaced (Score 1) 41

I find that surprising - I wouldn't think a jet ski would reduce range that much (to 144mi). A big trailer like a caravan or large boat, sure, that'll double your energy consumption / halve your range, but jet skis are pretty small. What version of X do you have, what sort of range reduction do you see when towing a jet ski, and how does your speed impact it? I'm quite curious.

I would have suggested "use a 3rd party charger", but then I remembered you're in the US and 3rd party charging infrastructure sucks :P There's only a single 3rd party charger on that entire route and it's CCS1/ChaDeMo, not NACS. There's not even a slow charger, unless you count Goffs, which is a bit of a detour.

Comment Re:EVs are not a solution beacuse of (Score 1) 228

Just for fun I decided to add the fuel mass in. Let's say it averages 70% full corresponding to a mean fillup at 40% full (probably ~25-30% on the meter). The 2020 Camry had a 15,8 gal gas tank, while the 2025 has a 13 gal gas tank. Gasoline is about 6 lbs/gal (God I hate US units....), thus altogether the mean added weight for the 2020 Camry is 66lbs, and for the 2025 Camrys (Camries?) is 55lbs. Full tank is 95lbs and 78lbs, respectively. Putting it all together:

Camrys with empty tanks:
Toyota Camry 2020 LE (FWD, non-hybrid): 3,241 lbs, 7.9s 0-60
Toyota Camry 2020 XSE (AWD, non-hybrid): 3,395 lbs, 7.8s 0-60
Toyota Camry 2025 LE (FWD): 3,594 lbs, 6.9s 0-60
Toyota Camry 2025 XSE (AWD): 3,774 lbs, 6.8s 0-60

Camrys with mean tanks:
Toyota Camry 2020 LE (FWD, non-hybrid): 3,307 lbs, 7.9s 0-60
Toyota Camry 2020 XSE (AWD, non-hybrid): 3,461 lbs, 7.8s 0-60
Toyota Camry 2025 LE (FWD): 3,649 lbs, 6.9s 0-60
Toyota Camry 2025 XSE (AWD): 3,829 lbs, 6.8s 0-60

Camrys with full tanks:
Toyota Camry 2020 LE (FWD, non-hybrid): 3,336 lbs, 7.9s 0-60
Toyota Camry 2020 XSE (AWD, non-hybrid): 3,490 lbs, 7.8s 0-60
Toyota Camry 2025 LE (FWD): 3,672 lbs, 6.9s 0-60
Toyota Camry 2025 XSE (AWD): 3,852 lbs, 6.8s 0-60

Model 3s (more space than a Camry, vastly higher performance):
Tesla Model 3 2025 SR (RWD): 3,880 lbs, 4.6s 0-60
Tesla Model 3 2025 LR (AWD): 4,019 lbs, 4.2s 0-60
Tesla Model 3 2025 Performance (AWD): 4,080 lbs, 2.8s 0-60

Model Ys (far more space than a Camry, still vastly higher performance):
Tesla Model Y 2025 LR (RWD): 4,235 lbs, 5.6s 0-60
Tesla Model Y 2025 LR (AWD): 4,392 lbs, 4.6s 0-60
Tesla Model Y 2025 Performance (AWD): 4,392 lbs, 3.5s 0-60

Is the massive 1700 pound weight difference between EVs of the same class in the room with us right now?

Comment Let's see... (Score 4, Interesting) 41

The solar, for a farm of this size in this location, maybe $1,20/W installed to be a bit pessimistic? But hmm, there's no AC conversion or grid connection, so maybe more like $1/W? Again, probably pessimistic, but let's go with it. 11MW = $11M

Tesla's calculator for 38,5MWh of Megapacks is $9,7M. Reduce the cost to get Tesla's internal cost, but increase it back to an even $10M for installation.

So total we're probably in the ballpark of $20M. Divided across 168 stall, that puts our capital cost in the ballpark of $120k per stall. V4 Superchargers are $40k per stall, so that's a total of $160k.

Assuming 20% capacity factor, there's a mean solar production of 2,2MW (call it 2MW after losses). So there's a mean power per stall of 11,9kW (not mean charge speed, as most of the time, any given stall is idle) - let's round to 12kW. If the cost is say $0,45/kWh, then each stall is earning a mean of $5,40/hr, or ~$47k, yielding a mean payback time of 3,4y.

This is of course a gross oversimplification - doesn't include maintenance, construction costs of other things at the site, other site revenue (convenience stores / cafes / etc), on and on and on. And per the article they also have a 1,5MW grid link, so it's not truly offgrid (just *mainly* offgrid). But the ballpark number makes this look very viable.

Comment Re:Makes sense. (Score 1) 40

ED: Last time I looked (when the tech was brand new) I couldn't find any studies on plants, but there apparently are now, and... yeah, it's what I expected. In fact, it's even worse than I expected: because all the energy is absorbed in such a short distance (the (living) epidermal layer), it does a lot more damage in that (critical) layer.

That said, apparently at lower doses you can still kill fungal pathogens without hurting the plants, and is much more effective at doing so, there is that.

I wonder if we should be exploring even shorter frequencies for plants. If you go shorter, bacteria are going to be able to escape harm, but you'll still be able to kill viruses and maybe still kill e.g. fungal condia.

Hmm. New thought (re: 222 / 233nm): as a pesticide.

Insect exoskeletons tend to be proportional to the insect's size. A big beetle's exoskeleton might be up to a couple hundred microns thick, while an aphid's only a several microns, and a spider mite's cuticle is just like 1-2 microns thick. And even with insects with exoskeletons too thick to kill, they typically moult, and after moulting, the new soft cuticle is initially far thinner. Also, with winged pets, the cuticle is often far thinner than on body regions (to keep them light and enable fast movement).

I bet far-UV would really do a number on small pests & winged pests. And... hmm... I guess that means we can go back away from the world of plants and back to the world of humans: surely it will kill skin mites, lice, etc... anything not hidden by clothes / hair / etc.

Comment Re:EVs are not a solution beacuse of (Score 1) 228

(And that's without fuel)

I went searching trying to figure out where you managed to find a 3241 lb Camry. Seems the 2020 ones were that light, but were non-hybrid, while the current ones are now all hybrid. Of course, it has an even more anemic performance of 7,6s 0-60, and is once again, still smaller than the 3.

To repeat, from the top: actual class competitors of the Model 3 are cars like: BMW 3-series (330i for the SR, 340i for the LR), Mercedes C-Class, Audi A4 & S4, Acura TLX, Infiniti Q50, Volvo S60, Jaguar XE, etc. And class competitors for the Model Y are cars like: BMW X3, Mercedes GLC, Audi Q5 & SQ5, Volkswagen Tiguan, Lexus NX, Acura RDX, Infiniti QX50.

Either compare apples to apples, or expect nobody to take you seriously. You might as well just say "BUT MY MOPED IS ONLY 200 POUNDS!!!".

Comment Re:EVs are not a solution beacuse of (Score 1) 228

Why on Earth are you comparing a SUV to a small sedan? Don't get me wrong, Model Y isn't exactly a GMC Yukon or anything, but it's much bigger than a Camry, with over double the cargo space (971L vs. 428L).The Camry has only 71% the cargo space of the Model 3. 7cm less front headroom / 5cm less rear headroom than the Y, and 4cm / 3cm less than the 3. And it's in an utterly different performance class. Are you, like, *trying* to be dishonest, or are you just this ignorant?

And even then, here's a stats table (US units for you). Tesla mass here and here and Camry here and here, for your disbelief.

Toyota Camry 2025 LE (FWD): 3,594 lbs, 6.9s 0-60
Toyota Camry 2025 XSE (AWD): 3,774 lbs, 6.8s 0-60

Tesla Model 3 2025 SR (RWD): 3,880 lbs, 4.6s 0-60
Tesla Model 3 2025 LR (AWD): 4,019 lbs, 4.2s 0-60
Tesla Model 3 2025 Performance (AWD): 4,080 lbs, 2.8s 0-60

Tesla Model Y 2025 LR (RWD): 4,235 lbs, 5.6s 0-60
Tesla Model Y 2025 LR (AWD): 4,392 lbs, 4.6s 0-60
Tesla Model Y 2025 Performance (AWD): 4,392 lbs, 3.5s 0-60

Explain to me how you think these numbers are somehow out of line with each other, given that even the 3 is larger than the Camry, and both are in an entirely different performance class?

Comment Re:EVs are not a solution beacuse of (Score 3, Informative) 228

You are talking nonsense. A Tesla Model Y battery is 1700 pounds, whereas a full gastank of a typical sedan is less than 150 pounds

SIGH.

First off, none of the battery packs in the 3/Y are 1700 pounds. The SR pack is 350kg / 772 lbs, while the LR pack is 480kg / 1058 lbs. This includes the charge cabling.

Secondly, unless you drive around in a vehicle that is nothing more than a gas tank or a battery pack, you're kind of forgetting a few things. Let's help you out.

ICE engines typically weigh 150-300kg (~330–660 lbs), and high-performance engines can exceed this. On top of this, the transmission usually adds another 70-115kg (150-250lbs). EV powertrains are light. An entire Model 3 drive unit, including gearbox, oil pump, filter, etc is ~80kg / ~175lbs. And actually this plays it down, because except in the performance Model 3 - which matches up against quite powerful / heavy ICE powertrains - they're software locked, so they're actually well oversized relative to what they're allowed to deliver.

ICE exhaust systems add ~25-45kg / ~50-100 lbs. Obviously absent in EVs.

ICE fuel systems (pumps, lines, etc) add another ~15-20 kg or so (maybe 30-50 lbs)

ICE vehicles, due to their inefficiency, require much larger radiators, coolant reservoirs, hoses, etc (again, another ~15-20kg extra over EVs).

The battery pack in an EV makes up the floor pan. Again, that cuts mass by a couple dozen kg.

The battery pack is a stiffening element, and eliminates the need for many dozens of kg of extra stiffening mass.

The needs of an engine block impose a lot more difficult design constraints on an ICE car, including a larger front end, a higher centre of gravity, a less compressible front end in an accident, etc. The need to compensate for these things also adds significant mass.

ICE vehicles have all accessories driven by the engine, and all electrics on low voltage (heavy wiring). EVs do it either with a DC-DC converter or direct HV, saving many kg again here. New EVs are also ditching the low-voltage battery altogether.

I could go on and on. The simple fact is, while EVs add (significant mass) in the form of one part, ICEs nickle and dime the car for mass all over the place. ICEs still win out mass-wise, but on a class-and-performance comparison, like-to-like, the mass differences just aren't that much (again, unless the designer is just bad at their job or doesn't care - *grumbles again in Hummer*).

(Also, re: serviscope_minor above: You don't compare vehicles by length; it's not a very useful metric. For size, you can compare by interior space specs - trunk / frunk volume, driver/front passenger head/leg/shoulder/hip room, rear passenger head/leg/shoulder/hip room. Length isn't a good proxy because it ignores packaging; a 1960 Chevy Corvette might be "long", but has very little interior space. Interior space and overall profile are often included as part of the category of "class" (for example, the Model 3 and BMW 3-series both have very similar interior space metrics and profiles). Also part of "class" is perceived / marketed luxury, though people differ over what counts as luxury, so it's not a very clear-cut metric. Performance is another axis, as higher performance cars tend to be heavier and/or have less interior space relative to their footprint (though EVs suffer a lot less on this than ICEs).

Comment Re:Makes sense. (Score 1) 40

You can't get sunburned from far-UV like you can with normal UVC. It doesn't penetrate deep enough to reach living skin cells (e.g. the (dead) stratum corneum is 10-40 microns on most skin, up to hundreds on e.g. palms and soles) - in human tissue, 222nm penetrates only a few microns, with most of the energy deposited in the first micron; the deepest any degradation was seen in one study was 4,6 microns (for 233nm, it's 16,8 microns). As mentioned earlier, the only cells it can kill are the outermost layer of cells in the eye (corneal epithelium), but they're constantly being shed regardless (the entire corneal epithelium is 5-7 cells thick and has a ~1 week turnover, so on average just over 1 day per cell on the surface).

The comments about material degradation probably are also not true with far-UV. It's certainly ionizing, but again it doesn't penetrate deeply into surfaces . Paint is generally many dozens of microns thick (a typical two coats of interior paint is ~100 microns), while epoxy is typically millimeters or more, so you're only going to be affecting the extreme outermost surface. I doubt you could even tell.

Also, contrary to popular myth (and indeed, our pre-COVID medical understanding), most common communicable diseases (influenza, COVID, most cold viruses, etc) spread by direct airborne transmission, not fomites (surface transmission). So how well surfaces are cleaned has no bearing on this primary means of transmission. That's not that surfaces don't matter - said diseases still *can* be transmitted from fomites, and some other diseases (esp. fecal-oral route ones like norovirus) are still believed to be primarily transmitted via fomites.

Again, honestly, the only thing I would have concerns about are plants. Most plant cuticles are only like 0,1-1 micron thick. Xeriphytes (desert plants) can be thicker, though, like 1-20 microns, and are in general adapted to more UV exposure, so might be able to deal with it. But I'd think a plant with only a 0,1 micron thick cuticle and a 0,1-0,3 micron thick cell wall will get its leaves pretty badly burned by far-UV. I'd expect any epidermis and stomata exposed to the light to be almost entirely killed. But if you had a cactus or plant with really waxy leaves, it might be fine.

Comment Re:That is a hell of a lot of words to say (Score 1) 163

That we should be cool with them blowing through billions of our taxpayer dollars so that they can throw shit at a wall and see what sticks.

SpaceX has saved the US government an immense amount of money. What are you even talking about? Falcon 9 / Falcon Heavy is by far the cheapest launch system out there, and is also, FYI, the most reliable launch system out there. And it go that way by exactly the process above. And that process cost far less than NASA spends to develop its super-expensive launch systems.

Comment Re:EVs are not a solution beacuse of (Score 4, Insightful) 228

Tesla has been at approximately mass parity with its closest class/performance competitors from BMW (with a full tank of petrol) since 2017 (the 330i vs. the SR, the 340i vs. the LR, etc). This "EVs are super-heavy thing" is a myth. I mean, sure, if you're terrible at your job you can design a really heavy EV (*grumbles in Hummer*). But usually, if the designers did their job right, the weight difference is small when matched up on class/performance competitors.

And beyond what others pointed out - that PM emissions are only a fraction of pollutants, and that they come from both brakes and tyres, and EVs have far lower brake emissions - it should also be pointed out that tyre PM tends to be mainly *coarse PM*, not fine PM. Both are harmful, but fine PM is significantly more harmful per amount produced. Brakes have a higher ratio of fine to coarse than tyres do, exhaust is higher still.

Cars also have air filters which capture PM. Generally well less than is produced, but I've seen a proof of concept where they amped up the air filtration so that the car was net negative. If you really wanted to, nothing is stopping you from mandating that. Still, economically your best bet is surely on taxing tyres (esp. studded ones) to incentivize people to choose durable ones and ones that don't wear down the roads, to limit hard accel / braking, etc.

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