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Comment Re:Truck Stops, Gas Stations, etc (Score 1) 904

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) 904

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) 904

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) 904

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) 89

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 Lots of room for methodology issues. (Score 2) 307

The lack of accidents and crime are more likely related to a general trend in crime going down from before they started turning off the lights. ... Give me at least one full year worth of data so I can compare it to the prior year, and have half of the country keep their lights on so It can be compared to the same time frame as well.

Hear, hear!

There's lots of room for methodology errors. Here's another:

Comparing murder rates between Great Britain and the US is complicated by differences in reporting. The US bumps the murder stat when there is a body and evidence of foul play. G.B. bumps it when they have a conviction.

Do they do that with other crime? If so, stable stats in the absence of street lighting might mean that any rise in crime is compensated for by a fall in identifying, apprehending, and convicting the criminals responsible. (Indeed, turning off the lights might easily result in LOWERED crime statistics at the same time it was causing a drastic increase in actual crime.)

Comment Re:Editors : WTF (Score 0) 307

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.

Comment Re:Batteries in Cold Weather? (Score 1) 904

If you add up all the auxiliary stuff you need to power with electricity and round up generously, it's maybe 2000 watts load. The very best commercially available technology of today can run that load for 45 hours. So the impact of the auxiliary system load is marginal. That means it's only a concern if you're contemplating using close to the maximum range of your car. If you're traveling 15 miles each way in an 84 mile range Leaf, or 80 miles each way in a 250 mile range Tesla S, you don't really need to worry about running the heater and lights, even counting diminished battery capacity.

The average American spends 25 minutes each way commuting; even in NYC the average figure is 34.6. Even double or tripling that commute time due to bad weather and halfing the range due to cold, that's still easy for the Tesla. It's a bit of challenge for the Leaf with its 24 kwh battery and 84 mile range.

If the typical electric cars of ten years from now perform close to the high end of today, then the vast majority of people won't have to worry about cold weather's effect on range. But a sizable minority of Americans are what the US Census characterizes as "extreme commuters": people whose commute takes more than 90 minutes or fifty miles each way. Even at the low end of that spectrum cold weather range won't be an issue, but if you commute from Fargo to Bismarck ND every day it's safe to say you aren't going to be going electric any time soon.

Comment Re:Trucking (Score 1) 904

While in general I think battery swapping is a stupid idea for cars (there's way too much need for different form factors, capacities, performance capabilities, etc, and it makes up such an integral part of the structure due to its size and mass and represents such a great amount of capital one would have to stockpile), I think it could actually work incredibly well for trucks. Rather than having them in the cab, I picture them slotting under the trailers (where various hardware is already often slotted), with a power connection to the cab. It would in such a situation be very easy to have a single form factor for the batteries and very easy to remove and reinstall them - you already have a standardized shape, easy undercarriage access, and the structural strength is already right where you need it. And whenever a truck picks up a new trailer that's been sitting around for a while, it could be already charged and ready to go. The cab would of course need its own batteries to haul itself around a good distance when not towing a load, but the trailers could basically hold the power for their own towing needs. And it would have little effect on an empty trailer's cost - it just needs the mounts for the batteries installed and the wiring to feed the cab, but would otherwise be a normal trailer haulable by any vehicle.

Comment Re:Error 1 (Score 1) 904

Indeed - and they can sell people on the concept pretty easily. Rather than saying "We're going to have you charge inside our store to tempt you to buy things", they'd sell the concept as "Remember back in the day when you used to have to fill up your car with gasoline out in the cold / heat / wind / rain / etc? Now we're enabling you to charge your car in comfort indoors in our stores because we love the environment so much and want to support people like you - you're welcome!"

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