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Can electric cars on the highway emulate plane-to-plane refueling?

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Re: Can electric cars on the highway emulate plane-to-plane refueling?

#61

Post by ianai »

patall wrote: post #44
yingw787 wrote: post #35

Earlier quoted context omitted.

Immediate concern for me would be safety. My impression is the battery pack provides a lot of the rigidity necessary to keep the car in one piece, and swapping the battery out introduces new hazards. There's also the concern about liability, whether the battery pack you're getting is as good as the one you're trading in (what if it's older and has a lower overall capacity), and how that might impact resale value. Thi…

That's why you would only use those for long distance trips and for everything else you would own that one old pack. Rigidity could indeed be a problem but so has been gasoline safety. There would need to be standards but there are also standards for charging plugs so, it is not like this never happened before.

Or have a built in battery and battery swap bay. Both can happen and no reason not do have both.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#62

Post by amirhirsch »

mgr86 wrote: post #58
amirhirsch wrote: post #50

Earlier quoted context omitted.

A car with a 40 mile range would be cheaper to buy, and a lot lighter so also more efficient. You could swap in a 400 mile battery when you actually need it.

The problem I have with the 40 mile range is that is highly dependent on 1. temperature. Extreme cold lowers range 2. topography. Inclines can drain a battery quickly. Declines can add range. 3. driving style. Do you have a lead foot? 4. Driving type. Are you on a highway?

You're nitpicking here. 60 mile range. 100 mile range. Whatever customer needs daily is far different from their outlier use cases. Most people with home/work charging never go below 40 miles from full.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#63

Post by ashtonkem »

vangelis wrote: post #59
willis936 wrote: post #21

Earlier quoted context omitted.

What about an autonomous semitruck that could run 24 hours a day except for unloading/reloading cargo, refueling, and maintenance?

A diesel electric duorail truck would be great for large freight loads.

Maybe you’re onto something here; what if we just rebrand trains to appease the car centric average American?

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#64

Post by willis936 »

bdamm wrote: post #24
willis936 wrote: post #20

Earlier quoted context omitted.

It seems like a valuable proposition if we threw out the existing paradigms of road transport. If we throw out concepts such as ownership of vehicles and fuel and treat all road vehicles as one system of controlled individual elements, you could envision is a more efficient solution. Traffic jams would be lessened, trip times would be shortened, total fuel usage would go down, etc. On road-fueling would be one elemen…

Many things are valuable if we throw out the constraints of dealing with existing reality. Even then I'm not sure it is valuable; roads suffer from lack of maintenance already. If anything we should be looking at how to make roads less expensive. Having autonomous vehicles disperse their weight to reduce prevalence of potholes, for example.

Right, and that is one thing to weight for when choosing the behavior of the system. While the article in question doesn't explicitly say this, I think these seemingly impractical solutions add to the theoretical toolkit that we can use to shape a road utopia, if society ever agrees on what that would look like. If society does ever agree on a road utopia and then consider it worthwhile to pursue, it will be valuable to have these ideas laid out. Perhaps they are useless today, but they motivate this idea. If they weren't proposed then the possibility of a future road utopia is entirely impossible.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#65

Post by ashtonkem »

zrail wrote: post #30
willis936 wrote: post #21

Earlier quoted context omitted.

What about an autonomous semitruck that could run 24 hours a day except for unloading/reloading cargo, refueling, and maintenance?

The thing that really feels possible to me is long haul autonomous trucks only on the highway. They can transport themselves between depots and then an actual driver does the tricky in-city transit and delivery/pickup.

I would be extremely opposed to this on efficiency grounds.

Semi trucks are awful. They’re horrible polluters, and they represent 99% of the road damage being done, despite only kicking in 35% of road upkeep cost. This is a drain on the public purse in exchange for more pollution and more accidents.

A far more sane policy would be to shift as much freight over to rail as possible, and reserve semi trucks for the last miles between rail head and customer.

Also, rail exists today. Self driving trucks don’t.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#66

Post by grecy »

pjkundert wrote: post #2

One of the next obvious steps for self-driving vehicles is “flocking” or drafting; this is an almost trivial problem once two or more vehicles are autonomously locked within a few inches of each other.

Tesla have talked extensively about "Convoy Mode" for the upcoming Semi Truck where they will do exactly that. Maybe the gap will be more than inches, but the idea is they draft together.

I think the plan for early autonomous driving is the first one in the line will have a human driver, and the others will follow autonomously in convoy.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#67

Post by letitbeirie »

Emulating plane-to-plane refueling entails all sorts of system dynamics problems because of the untrained human driver in the mix.

Wouldn't it be a lot easier (and likely cheaper in the long run) to emulate overhead line-to-train power transfer?

Seems like "transfer of electricity into an (ideally) land-bound vehicle from its infrastructure" would be a more closely related problem than "transfer of fluid from one airborne aircraft to another."

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#68

Post by frosted-flakes »

ianai wrote: post #57
NickM wrote: post #39

Earlier quoted context omitted.

It was abandoned because fast charging stations keep improving, and are much simpler and cheaper to operate than battery swap stations. It's already at the point where you can take a 400-500 mile road trip in a Model 3 with maybe a single twenty minute charging stop, which is just not that much extra time, and most people like to take a short break every few hours anyway. I suspect Tesla knew this would probably happ…

I’d still like to be able to tow a battery behind me for extended trips. I don’t know how running the AC impacts range, I would like to know. Places with extreme weather and major population centers can make an otherwise short drive really taxing on resources through ac use or just being stuck in place for extended periods of time. Like how peak LV traffic can turn a 15 min drive into a 50 minute drive in 120f+ heat.…

That seems like a fantastic idea. This way, the car's internal battery can be smaller and lighter for day-to-day use (and therefore more efficient), and whenever longer range is needed you can just rent a fully-charged tow-a-battery, which you can swap out like propane tanks, or recharge yourself at home. These tow-a-batteries would work with any electric car with standard secure hook-ups.

Since these batteries would be rather expensive, I imagine that you would have to pay a refundable deposit to the tow-a-battery network (Shell, Esso, etc.) that covers the full cost of the tow-a-battery in order to rent one.

The biggest down-side is that a rear-end crash could be rather dangerous. I don't see a way around that without making the tow-a-battery a vehicle in itself.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#69

Post by ravenstine »

Retric wrote: post #46
ravenstine wrote: post #38

Earlier quoted context omitted.

What reason would that be? I always assumed that was because of the pursuit of slimmer phones and to discourage repair.

It’s also a more complex and expensive. Swapping cellphone batteries means you need to own another battery which few people did once capacity increased. With cellphones people that want a swappable battery can just get an external battery pack but most people can simply recharge daily.

> Swapping cellphone batteries means you need to own another battery which few people did once capacity increased.

That doesn't make sense to me. Sure, maybe you can't get an OEM battery, but I've owned cell phones in the last 5 years that I easily swapped out the old battery with an aftermarket battery for about $12. I think people have the ability to buy batteries.

> With cellphones people that want a swappable battery can just get an external battery pack but most people can simply recharge daily.

My OG Pixel phone is on its last legs in terms of battery capacity, which means it will probably get scrapped(even if I trade it in somehow or get it "recycled"). I would have swapped the battery with a new one, but I don't have that option. At least without risking damaging the phone on disassembly. Recharging daily isn't a solution because it runs out of power in about 5 hours without even using it.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#70

Post by frosted-flakes »

njarboe wrote: post #47
ashtonkem wrote: post #22

Earlier quoted context omitted.

Trains. The fact that long haul semi trucks are a thing is a failure of infrastructure. Edit: as some have pointed out, it’s more a failure of policy.

100 trucks running right up next to each other is a train. I could imagine train operators converting their right of ways to a system where each train car can be autonomous and can leave the train and track without disruption. As the train comes by an exit location (station), the cars that need to get off just come out of the train and leave while the train tightens up again for aerodynamic efficiency and continues o…

I don't see that happening. Train cars are incredibly simple things that have barely changed in many decades, probably because it's hard to introduce changes when all the cars need to be compatible with one another. Train cars don't even have electrical hook-ups, just air brake lines.
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