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Comment Re:Truck Stops, Gas Stations, etc (Score 1) 732 732

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) 732 732

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) 732 732

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) 732 732

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:quickly to be followed by self-driving cars (Score 1) 732 732

I'll go further and wager that in an average American city, beds are used on average less than 30% of the time. Most clothes are in use less than 10% of the time.

Let's take your model to the logical extreme. We'll share our beds and housing so that we get optimum use from them, as well as share everything that is bulky and seldom used, and carry our (few) our personal possessions on our back in a duffel bag.

Move to a new city? No problem! Clean uniforms are waiting for you there, so there's no need to carry much more than the clothes on your back. Just throw the duffel into the back of the Electric Carriage and be shuffled off to a new place!

Wife and kids don't want to go? No big deal, we'll just share those, too! Just be assigned a new family at whatever sleeping tube structure you decide to call "home," and your old family will await similar and complete male utilization at their old tube structure.

Also: We don't need to own books; we have libraries! We don't need to keep pets; we have zoos! We don't need underutilized personal kitchens; we have restaurants! We don't need personal computers; we have public terminals! We don't need currency; everything is provided for you!

From each according to his ability, to each according to his need!

tl;dr I like owning and driving my car.

(See also: THX-1138)

Comment Re:Raspberry Pi (Score 1) 109 109

But you can't have it.

There isn't enough bandwidth in the ISM bands to support what you want.

You'll always have to run at least one wire. And by the time you run one wire, you might as well run the rest of the wires that you need.

And then you'll wind up with a solution that always works, instead of a solution that (currently) cannot exist because wireless spectrum is a finite resource and your needs are beyond its capacity.

Comment Re: Wow (Score 3, Insightful) 62 62

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:Dubious assumptions are dubious (Score 1) 210 210

I'd be curious about the distribution of the lights. Turning off lights in cities isn't going to help astronomers much. And if they're turning them off in places where there are few people walking, such as rural lanes, it might help astronomers without hurting pedestrians. (Criminals would be less likely to gather there, though those pedestrians had better be really aware of cars.)

I could see it working if there were more streetlights than we really needed. If that were the case, it could yield positive results. But it would also be invalid to extrapolate from those to the majority of lights in more densely populated places.

Comment Re:Doubtful (Score 1) 732 732

Indeed. There was an article floating around a few months ago with a hypothetical review of a gasoline-powered car if electric cars dominated. A lot of the downsides of ICEs that we take for granted would be really aggravating if we hadn't grown up with them.

Gasoline Car Test Drive: Noisy, Wasteful, Polluting, Fast But Pricey Refueling

Comment Re:quickly to be followed by self-driving cars (Score 1) 732 732

Even for you, there could be considerable advantages to hiring an automatic car rather than owning one. You offload the maintenance overhead (though that's smaller for an electric car than an internal-combustion engine); that doesn't save money but it does save time. What would save you money is if your car were off servicing four or five other families during the times you didn't need it. Cutting a $30,000 expense by a factor of 4 or 5 would be a huge cost saving to you. Even if the service imposed an overhead of a factor of 2, it's still not an amount of money you'd give up on lightly.

It need not even reduce your flexibility, if you could summon anybody's car on five minutes' notice. It's easy to see how that could happen, if large fleets were deployed strategically, even in the suburbs. (It would work less well as the density dropped, but even in a residential neighborhood, a car can move a fair distance in five minutes. Your house, your work site, your grocery store, etc. are all likely to be five minutes from a lot.)

There are still advantages to just having your own car. Mine is full of my crap, for example. I haven't taken my toolbox out in a while, but I will, and I don't know when. If I were calling for a car every day I wouldn't lug my toolbox around, and thus wouldn't have it. Customization is nice. Not having to worry about peak usage times would be nice (though peak usage will also coincide with peak traffic, which I try to avoid anyway).

Still... I'd consider ditching a car entirely if it saved me that much money. My car hit 200k miles, and while it's a Honda, I'm still gonna need to fork out $20k within the next few years. (I'm cheap, and don't want a luxurious car. I just want it to get me places.) A two-car household would likely make it very compelling to at least split the difference.

Comment What is the prognosis? (Score 1) 56 56

Hands are just incredibly complicated. There are a lot of tendons and ligaments in there, and I imagine that fine motor control comes from a lot of different nerves. How much dexterity can he be expected to get out of this?

I imagine that getting it done young means that he's got years to re-establish connections and train pathways for it. Still... anybody know how good it might get? Will he be able to play the violin?

Comment Re:And the NSA? (Score 1) 211 211

Actually, they probably included a few big wrenches to assemble some of the rack systems, so they probably have the tools to break even 1024 bit encryption.

When you say "1024-bit encryption" you're talking about RSA, which is a completely different problem. 1024-bit RSA are too small to be used today and should be replaced.

2048-bit RSA keys, however, are roughly equivalent in security against brute force to a 112-bit symmetric key, and will be secure against anyone for quite some time. 3072-bit RSA keys are equivalent to a 128-bit symmetric key. Excascale, even yottascale, computers won't touch them.

But everyone really should be moving away from RSA anyway. ECC is better in virtually every respect. To get 128-bit security (meaning equivalency to 128-bit symmetric key), you only need a 256-bit EC key.

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