This is called a train.
Also, overhead lines are actually really awful for a variety of reasons. Safety, efficiency, maintenance, etc. This is why you rarely see them used anymore. Third rails are the way.
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Low odds of this, but if batteries become standardized for electric vehicles and they are located in easy to access places then I could see a switch from gas stations to battery stations. Instead of having to attach an EV to a charger at a station, the station swaps the EVās dead/nearly dead battery for a charged one.
Granted, by the time thatās practically feasible, battery and charging tech may be good enough it isnāt needed.
FYI
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I was sort of under the impression that overhead lines were mostly opposed for bad reasons (thereās plenty of good stuff that you donāt really see anymore for bad reasons) but I could be completely wrong about that. Also I absolutely just want a train like 99% of the time.
People have played around with battery swap ideas a bit. Thereās a lot of technical tradeoffs but I donāt think itās going to happen with lithium and is unlikely to happen at all unless people are willing to trade a bit of power for a safer more flexible setup (probably easier to convince Americans on mass transit)
Yeah, this is a decent possibility. There are a lot of minor but significant differences, though, that could cause an issue.
First, not all batteries are created equal, and they wear out over time. Imagine you buy a brand new fancy car with brand new batteries. You run out of juice and go to the station. They swap them for some batteries that are well used. Still functioning, but not as good. The brand new batteries you paid for get recharged and put in some other car. You never see them again. Batteries are not as fungible as fuel.
Batteries take a lot of space. Even if you wire them up with enough electrical infrastructure to do the charging, where do they put all those batteries while they are charging?
Batteries are heavy, youāre going to need some staff and equipment to remove them from cars and put them in cars quickly.
Vehicles are different. While Iād love to limit them and standardize, someone is going to have a vehicle that needs more or less power. A battery swap standard that can accommodate both an electric Civic and an electric Econoline van is going to have issues.
Batteries can break, fuel mostly canāt. A station loads some broken battery in your car and maybe they just donāt work. Maybe they break your car! Maybe they just swap again to give you some working ones, but now theyāre running low and customers needing a swap have to wait for charging.
I look at how Citibikes are managed in the city and there are frequently issues where docks are full, and you canāt park. There are also situations where you want a bike, but the dock is empty. Sure, gas stations can, and have, run out of fuel. But some stations are going to have too many charged batteries and others are going to have too many empties and the demand is going to be in the wrong place at the wrong time.
Benefit, no exploding gas stations!
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Yup, the work around to most of that is to have several smaller battery modules but then they need to be in parallel because you have to pretty carefully match cells in series. But to get crazy power output you need high voltage which means lots of cells in series. Typical EVs are about 360V nominal, which means 95-100 cells in series (for Li-ion). Itās complicated.
You can absolutely build a small vehicle that runs at lower voltage and use LTO or LiFePo4 instead of Li-Ion for more of a safety margin but no one is doing that for capitalist reasons.
This seems relevant to the current topic. Just announced today:
https://www.washingtonpost.com/transportation/2022/02/10/electric-vehicle-charging/
Biden administration plan calls for $5 billion network of electric vehicle chargers along interstates
ā The Biden administration laid out plans Thursday for a $5 billion network of electric vehicle chargers along interstate highways, aiming to boost confidence in battery-powered cars by ensuring drivers can always find somewhere to plug in.ā
Thatās good but I donāt have a huge amount of hope for states to do it right. Most states have been basically thinking of them like gas stations but what you want is charging infra near walkable stuff so you can leave your car and do something.
My favorite road trip chargers are in downtowns kind of near a highway. Restaurants, coffee shops, and bars nearby, you can wander around and see a small townās little museum or art gallery or whatever. The worst ones are just like a rest stop next to the highway or in a giant parking lot that youāre not sure if youāre allowed to park in because itās for a college or convention center or something.
Also speaking of lock-in, we could have some kind of open standard or whatever but Iām sure most states will just partner with one of the larger mediocre companies that requires an app to interface with the charge station.
Thatās getting more common in China, funnily enough! Thereās a bunch of places you can go in major cities to exchange a flat battery, and itās fast, too. IIRC, every battery is tested, and anything that falls below spec is sent out for reconditioning. Literally all done by machine in a few minutes, in a joint that looks almost like a car-wash. There are some restrictions - some cars canāt use some stations, there arenāt universal ones yet - but itās pretty cool. Used for fleet cars a lot, apparently.
Edit - found a video:
https://twitter.com/DSORennie/status/1473591277589463040?ref_src=twsrc^tfw
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Speed-wise, weāre already at fast chargers for cars taking 15 to 20 minutes for some to get nearly full and likely going to have that time keep going down. The biggest asset to battery swapping over fast charging is the avoidance of degradation to battery capacity that fast charging can cause, though hopefully thatāll also be improved as charging times go down.
Both solutions still have one major obstacle the US has consistently been bad at for a bit, infrastructure. Even in areas with a great selection of fast chargers, theyāre often unavailable, which was an issue both of the times I mentioned being stranded.
Next year Formula E is going to introduce mandatory pit stops for fast charging. I donāt know if thereās going to be a single provider of the technology, or if different teams can spice the tech from different manufacturers, but itās an attempt to mainstream the idea.
Seat moving motors probably draw like a millionth of the power the moving-2-tons-of-metal-around motors.
I donāt think removing them from a green perspective really rates.