Definitely more than a concept; I've worked on actual demos where cars drove long distances on such roadways. But they are expensive.
Hydrogen vs battery storage
- Thread starter billvon
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exchemist
Valued Senior Member
Oh sure. Trolley buses were around in the 1930s. Under road charging is new though. But what I really meant is evidence of commercialisation of either seems to be absent.
That's what I am talking about. There are at least two systems out there that are commercially available. No one has been interested yet.
exchemist
Valued Senior Member
I suppose it's hard to see what the business process would be to lead to such a system taking off commercially. Perhaps installing a strip on some interstate, at the kind of distance that would otherwise trigger range anxiety, in a state where there was a high population of EVs that could be fitted with the charging system. Maybe piloted by a fleet of long distance buses or something. But the obstacles to it becoming a nationwide system seem huge.
There's a huge chicken and egg problem with them. No state/city/toll road operator is going to install them until there are cars that can use it (and be charged for it) and no prospective car buyer is going to buy one unless there are roads that support that system.
If it happens at all it will be because Fedex/UPS/Amazon decides it's worth it to electrify a few stretches of roads and do their trucks at the same time, to extend the range of their electric fleets.
exchemist
Valued Senior Member
Tell me, how long a strip do you need to charge a medium sized car, travelling at say 50mph, to get a 70% charge? Are we talking 5 miles, 10 miles or 30?
The systems we were designing went to 20KW. So you'd need 4 hours to go from 20% to 70% charge. Length of course depends on how fast you're going.
But the goal was never to charge while driving (although that was a nice side effect.) The goal was to power the car while it was on the road, and leave the "heavy lifting" of charging to stationary chargers while the car was parked.
exchemist
Valued Senior Member
Oh I see. That makes sense. The pic posted by Ken Fabian is a bit misleading then, showing it as a "charging" lane.
Yep. And the thing you plug a car into to charge at home isn't a charger either - it's an EVSE (the charger is in the car.) Terminology for this stuff isn't always exact.
exchemist
Valued Senior Member
Oh I’d assumed that was a charging socket and a charging cable. Is it more than that?
It's just a charging cable with some electronics to provide a pilot signal and a very good GFI protector. Commercial ones also have RFID readers and the like.
But it's regularly referred to as a "charger" as well. i.e. "that shopping center has six chargers!"
Ken Fabian
Registered Senior Member
I don't know that in-road charging systems are as good as they can get yet - big advances may need a lot more actual doing. Nor how good they have to get to be considered a real option to roll out in a big way. How 'good' may probably be described as how cheap and none of this will be cheap.
For delivering the power levels road freight would need, especially if actually intended to charge big batteries rather than just giving batteries a break, the overhead type looks better; I'd be more inclined to focus on the in-road kind of technology on hands free induction charging for car parking spaces, promoted for the convenience with the public and promoted for the Vehicle <=> Grid potential and daytime charging (maximising solar energy) for grid owners and operators.
Seriously I don't see that level of serious investment or overarching commitment to decarbonising happening. China might; their ability to take on big long term projects is both heartening and alarming.
Hydrogen/ammonia takes major commitments to infrastructure too but without necessarily utilising 'public' infrastructure.
I keep circling back around to battery swapping which similar to building up Hydrogen, could roll out initially servicing a few dedicated major freight routes. Sort of similar to that is happening with mines using electric trucks; they have set routes.
Not sure to what extent battery swapping would require more batteries overall. More batteries than trucks, yes, but what the trucks carry on-board could be smaller and used more efficiently, ie less need for overcapacity. Nor sure to what extent a lot of big batteries on chargers can provide (and earn extra income from) grid services like dedicated grid batteries can.
For delivering the power levels road freight would need, especially if actually intended to charge big batteries rather than just giving batteries a break, the overhead type looks better; I'd be more inclined to focus on the in-road kind of technology on hands free induction charging for car parking spaces, promoted for the convenience with the public and promoted for the Vehicle <=> Grid potential and daytime charging (maximising solar energy) for grid owners and operators.
Seriously I don't see that level of serious investment or overarching commitment to decarbonising happening. China might; their ability to take on big long term projects is both heartening and alarming.
Hydrogen/ammonia takes major commitments to infrastructure too but without necessarily utilising 'public' infrastructure.
I keep circling back around to battery swapping which similar to building up Hydrogen, could roll out initially servicing a few dedicated major freight routes. Sort of similar to that is happening with mines using electric trucks; they have set routes.
Not sure to what extent battery swapping would require more batteries overall. More batteries than trucks, yes, but what the trucks carry on-board could be smaller and used more efficiently, ie less need for overcapacity. Nor sure to what extent a lot of big batteries on chargers can provide (and earn extra income from) grid services like dedicated grid batteries can.
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The problem is that the battery sets much of the performance for the car (both range and maximum acceleration.) Unlikely that anyone will be happy swapping their brand new battery for one with 75% of the range and 60% of the acceleration.
Ken Fabian
Registered Senior Member
I was suggesting battery swapping for trucks rather than private cars.
There wouldn't be any "my brand new battery" - there would be a pool of battery packs. I would imagine the battery packs as well as the vehicles would need reliable capacity estimation - meters/gauges/displays of kWh capacity and probably logs of usage - and some quality control is needed to prevent poor performing batteries staying in the pool. I expect paying for each battery's worth at a time, but it doesn't have to be.
There are hurdles to overcome but I don't think your scenario is a likely one. I don't know if the offerings of CATL that include battery types with (claimed) 5 years with no capacity degradation are suitable but it does seem like batteries can be a very reliable technology. China seems more likely to try whilst it seems unlikely there will be any serious policy in the US to decarbonise transport - but very possibly serious policy to prevent it.
Other than hydrogen and hydrogen-as-ammonia the other available options seem to be bio-fuels and manufactured liquid fuels. Manufactured fuels seem to more often be variants of bio-fuels and/or tied to CO2 capture and/or Hydrogen as feedstock - which can look more like holding out for 'better' in lieu of doing anything now - oh, too bad, we have to keep making FF models.
I remain dubious of the economics and ability to scale up bio-fuels - agriculture for food needs to have priority.
Я не разбираюсь в автомобилестроении, но может вы мне подскажете: я видела велосипеды, у которых на колесе стоит приспособление, которое подключено к фонарю на руле. Колесо крутится при движении, и фонарь светит. Т.е. велосипед сам для себя вырабатывает необходимую электроэнергию. А можно ли то же самое сделать с автомобилем? Чтобы он сам себя заряжал вырабатываемой при движении энергией? Ну, приспособить что-нибудь такое похожее к колёсам?
И солнечные батареи на всю крышу, плюс скомбинировать с ветряком(автомобиль же испытывает давление воздуха при движении, причём немалое, как при урагане).
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Yes, for fleets, swapping would work a lot better.
Given that obesity is one of our top health challenges, I am not convinced that we should be prioritizing growing more sugars and oils for human consumption. I do agree that we cannot substitute all our current fossil fuel needs with biofuels (the scale doesn't work.) But a likely future involves vehicles like PHEVs to greatly reduce fuel needs, with the balance supplied by (expensive) biofuels.
I used about a gallon of gas a month in 2024, on average. At that consumption rate, US private vehicle demand could be supplied by biofuels.
Electric cars already do this. They "charge themselves" when braking. However, this does not work during normal driving, because the energy recovered is ALWAYS less than the energy used to drive the car. That's a law of thermodynamics.
Да, я знаю. Но разве основную энергию не могут давать солнечные батареи и ветрогенераторы?
Sure. In that case, the energy is supplied by those sources.
А если поставить их на крышу автомобиля? Это будет работать?