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Comment Re:Sudden outbreak of common sense. (Score 1) 158 158

If I see a coin come up heads nine out of ten times, I'm expecting it to come up heads on the eleventh toss.

You exactly demonstrated the problem with common sense reasoning. People assume that because they have what feels like to them (and may actually be) extensive experience with something they automatically understand it. But most people who haven't been trained in mathematics have plenty of misconceptions about what mathematicians call the "Bernoulli Process" (coin flipping).

Comment Re:Why go without GPS? (Score 2) 23 23

On the Moon or Mars they wouldn't reach very far. But a RTG-powered version on Titan would have unlimited range (although may need to land periodically to recharge its flight batteries). And even a rocket or gas jet version would have quite significant range on an asteroid.

Such a design is obviously going to be very mission sensitive, hence the need for different propulsion systems. Some missions would benefit significantly as well from wings to allow for long distance flight on bodies with atmospheres (Venus, Titan, maybe Mars, etc). A couple worlds, such as Titan, might benefit from landing floats. And so forth. But that's where rapid prototyping tech (such as 3d printing) becomes useful - they engineer the base model and then can play around with variants with ease. Hopefully in the end they'll have a sample collector module with a workable version for almost any body in the solar system. And for the interests of science, we really need something like that, a universal adaptable drone module - to be paired with a universal adaptable ion tug module, one of a couple variants of a universal adaptable reentry / landing modules, and the same for adaptable ascent modules.

It's impressive what science can be pulled off on the surface of another world. But it's nothing compared to what we can do here on Earth with a sample return.

Comment Re:Truck Stops, Gas Stations, etc (Score 1) 840 840

In one truck, yes. The frequency of dead batteries, however, will be the same as passenger vehicles; who will dispose of those?

Seriously, you can't be this daft. The operator, of course, with the price rolled into the service cost.

All of which are relatively involved.

No, they're not. Even your laptop battery estimates its capacity, and that's about as simple as li-ion battery packs get. Coulomb counting, voltage measurements at start and end compared to the charge temperature, charge voltage curve shapes, direct measurement of pack heating over the course of charge to measure internal resistance, and about half a dozen other methods are all usable and widely used to estimate capacity remaining in a pack. Pretty much every modern EV and hybrid in existence checks its battery pack's performance at least at the pack level, if not the individual cell level (Tesla does it at the "brick" level), to see how it's aging and when components or the pack as the whole need to be replaced.

Measuring remaining battery capacity is a concept older than the light bulb.

testing and inspecting a battery for damage and danger conditions so you don't install it into someone's vehicle and get a lawsuit for "vehicle exploded in a giant flaming blaze" (or drive all your customers away with "we don't test our batteries for anything but charge, and damaged batteries may set your truck on fire") is wholly different.

Just like gas stations check their gas for impurities that can cause damage to an engine? No, it's the manufacturer's issue to ensure that the product meets its stated usage specs - in this case, the specs including safe handling of damage and X number of swap cycles. Meeting damage control specs is why Tesla isolates each cell in a canister to prevent failure propagation. And why packs always come with fuses/breakers that blow when the pack gets wet or there's otherwise a short.

(Just ignoring that many types of li-ions don't burn even when abused. Tesla uses standard cobalt-based 18660s, which is why they have to have a failure isolation system, but vehicles like the Volt and Leaf use more stable spinel chemistries)

That may result in diesel being the cheaper fuel by far

Tesla's battery packs have an 8 year, unlimited-mile warranty. Even if we assume that they're only good for 1000 full charge cycles (which should be well on the low end), at 30 tonne-miles per kWh of charge, times 1000 cycles, and $150/kWh for the pack, that's 200 tonne-miles per dollar of pack capital cost. A diesel truck will get about 120 tonne-miles per gallon of diesel, and diesel costs somewhere in the ballpark of 6x more than electricity per unit range (depends on your location), meaning that the electric version saves about 3-4$ per dollars of energy cost per dollar of pack capital cost.

There are a lot more batteries on a truck.

Wait, so you're picturing them being done individually, one after the next? Seriously? *smacks forehead*

Fortunately, if you mount batteries under there without a bunch of armored doors and other shit to hold it all together, the cargo container catches fire when the batteries become damaged.

In the parallel world where EVs are always catching on fire, and petroleum-fueled vehicles aren't - quite unlike our actual world.

Comment Re:First note to the PAs on the new show: (Score 4, Interesting) 189 189

You know, that would be the best prank ever. Convincing Clarkson that he's getting a new TV show but having the actual point being to secretly film him when he's not acting for the fake "show", as they subject him to situations that would be increasingly uncomfortable for a speed-obsessed labour-hating hot-headed racist diva. Sort of "Top Gear" crossed with "An Idiot Abroad". ;)

Comment Re:Sudden outbreak of common sense. (Score 2) 158 158

Not really. The judge simply ruled she was bound by precedent that her court did not have sufficient authority to overturn. That's actually a good call, but it has nothing to do with the issue or arguments.

In any case appeals to "common sense" aren't worth squat when that common sense is based on ignorance or inexperience. It's common sense to talk about "the dark side of the Moon" or to think that the next flip of a coin is affected by prior flips.

For 80% of the existence of our species we coexisted with at least one other species that would pass any reasonable philosophical criteria for "person": the Neanderthals. If we were able to use biotechnology to recreate Neanderthals, Jurassic park style, there's no question that if successful the experiment would create people. But would they be legal persons?

It's an important philosophical question because it potentially colors a lot of mundane ethical questions. Do we recognize the rights of others as a kind of tribal convention? Or are we compelled to do so because of something in human nature? If the latter presumably non-human entities would have an equal ethical claim to personhood.

Comment Re:Truck Stops, Gas Stations, etc (Score 1) 840 840

How old are the batteries? Do you own your battery? What is a battery worth? Do you load your truck with aging, unreliable batteries to swap-off with other aging, unreliable batteries?

When it comes to a truck which will have a sizeable number of large batteries, you're pretty much statistically guaranteed to never have more than a dud or two so long as the battery management process is sound.

As a service station manager, how do you test each of these batteries to ensure its safety and reliability (its level of aging)

By, for example, any of the dozen or so methods already used for this purpose?

As a service station manager, how do you offset the cost of rotating out old batteries traded in by truckers?

By rolling that into the swapping cost?

Could you please ask questions a little harder than "What does 1+1 equal?" I'm seriously not getting why you don't already know the answer to these questions you're asking.

Changing batteries in something like a truck is a labor-intensive process.

Wait a minute, you think that when people talk about battery swap they're talking about someone going up and swapping batteries by hand?

mounting may preclude a fast removal operation.

Many companies have already demonstrated battery swap for cars, which is a far harder target than trucks. With trucks, my preferred mounting is on the trailers themselves (with the cab having its own, non-swappable batteries). You already have, today, stuff mounted to the underside of trailers. It's right where the structural strength is already located and you have tons of open space underneath for easy access and standard form factors. It's an order of magnitude easier challenge than for cars, which you practically have to have disassemble their frames to get their batteries out.

The operation may take 40 minutes overall

Battery swap in the much harder case of cars can be done in less than a tenth that time.

Mounting the batteries affects balance, thus handling, thus safety

And you're envisioning that one would load all of the batteries only on one side or something...?

Think about it as if you were going to swap an entire, pre-filled gas tank

And think about having the tank you plan to switch out be a standardized external tank mounted in a standard form factor on a standard trailer.

Comment Re:Truck Stops, Gas Stations, etc (Score 1) 840 840

Assuming an overall pack energy density of 200 Wh/kg, 1kWh would weigh 5kg. A typical truck may move around 1 tonne 120 miles per gallon of diesel. A gallon of diesel contains about 10kWh of energy. An electric motor will use it about 2,5 times more efficiently than a diesel ICE, so 120 miles per gallon of diesel equates to 300 miles per 10kWh of electricty, or 30 miles per kWh electric, or 30 miles per 5kg of battery pack. So every 30 miles of range you want takes up 0,5% of your cargo mass. If you want say 300 miles range then it would consume 5% of your payload.

On the other hand, the price difference in the cost of fuelling the truck (diesel vs. electricity) would be massive. For each tonne of cargo (assuming 300 miles vehicle range and an average haul distance per hour of say 60 miles), giving up 50kg of cargo to enable to you spend $0,30 on electricity ($0,10/kWh) instead of about $1,80 on diesel ($2,70/gal), or a savings of $1,5 for giving up 50kg of cargo. If we scale to say 50 tonnes of cargo then this equates to giving up 2,5 tonnes (5%) of your cargo to save $75 per hour.

Comment Re:Trucks will be hybrids, not pure EV (Score 1) 840 840

There have been electric delivery trucks for a long time - for example, Smith Electric Vehicles has been making li-ion trucks almost as long as Tesla has been around. And they follow up on a long history of electric delivery vehicles on a continuous line dating back to the early lead-acid days. But "existing" doesn't mean "having blown the market wide open". The big question is when that could happen.

You know, though, as ridiculous as it sounds, I almost wonder Tesla's efforts could evolve into a killer delivery vehicle. The Model S / Model X drivetrain is already starting to get into the power range of a big rig, and big rig budgets can afford their high prices. Combine that this potential solution to charging over long distances and you really could have a winner.

Comment Re:Truck Stops, Gas Stations, etc (Score 1) 840 840

I wouldn't count on really powerful fast chargers ever getting really cheap. Cheaper than they are now, sure, but just ignoring all of the communication and high power conversion hardware you still have to have:

1) A powerful cooling system in your charger (for a really powerful connection, you even need to liquid-cool the charging cable)
2) A huge amount of copper (or aluminum, but that comes with a number of additional challenges) in your charger
3) A high power feed installed to your location
4) A high capacity and high power battery buffer to even out your charges if you want really fast charges / fast charges for big packs (say, 250+ kW)
5) A professional electrician to do the installs (and remember, we're not talking about home wiring here, we're talking about huge-current high-voltage connections). ... and so forth. These things will always add up. So maybe we'd not be talking about $100k to add one.... but I'd be shocked if even in mass production they could be manufactured, delivered and installed for under $10k. Probably several tens of thousands of USD per unit.

Comment Re: Wow (Score 4, Insightful) 84 84

I wouldn't be surprised if they could get some more specific clues on what water it's been in - for example, marine growth species types or isotopic ratios - to help pin it down better than just general drift calculations (lots of places could dump debris on Réunion). There are could also be potential clues on how much sun or what temperatures it's been exposed to, such as rates of plastic degradation, and perhaps that might also help give them better ideas of what areas it's been in based on weather patterns since the flight was lost.

There are so many potential clues... each one rather vague on its own, but all together, I imagine they'll get pointed in the right direction.

Comment Re:Editors : WTF (Score 0) 285 285

Technically it's giving smaller amounts of something, not taking anything away. Nonetheless marginally it makes perfect sense to talk about "doling out cuts". It means starting with a total net cut and dividing the marginal impact among several parties.

Yes, it will raise a few eyebrows among editorial prigs, but it's perfectly clear what "doling out cuts" means.

"And do you think (fop that I am) that I could be the Scarlet Pumpernickel?" -- Looney Tunes, The Scarlet Pumpernickel (1950, Chuck Jones)

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