General > General Technical Chat
EV-based road transportation is not viable
tggzzz:
--- Quote from: rstofer on February 16, 2023, 10:15:04 pm ---
--- Quote from: tggzzz on February 16, 2023, 09:54:46 pm ---A charger must have the ability to read a payment device, authenticate credit availibility, debit someone's account, and communicate that to the user.
--- End quote ---
Gas pumps already do this and have for a long time.
--- End quote ---
There are indeed tens of thousands in nice roomy dry above ground cabinets.
That's very different to tens of millions buried below ground in cramped and wet holes.
--- Quote ---
--- Quote ---I would prefer to listen to the experience of someone used to working in/under roads than someone presuming it is easy. The last time I had that pleasure was, gulp, 42 years ago at BT Research Labs. Eye opening.
--- End quote ---
But it is already known how to do this. I don't know how but there are thousands of people who do. This is just a tiny detail. BTW, we did that at a company I worked for when we wanted to run an 8" chilled water line among 3 buildings without tearing up the lawn and buried utilities. Worked well!
--- End quote ---
My point remains.
tggzzz:
--- Quote from: tom66 on February 16, 2023, 10:46:14 pm ---
--- Quote from: nctnico on February 16, 2023, 10:36:43 pm ---Yes and no. EV charging stations typically don't accept debit or credit cards. OTOH every manned / unmanned gas pump does. For some reason companies that run EV chargers deemed it necessary to invent their own cards which are not interchangeable.
--- End quote ---
Err... how many have you used? Every new DC charger in the UK has to accept contactless payment, and a good majority of older ones do already. (They don't require PINs so no keypad is needed, just a contactless reader.) This also appears to the way the EU is going. The vast majority don't bother with RFID cards any more because yeah, it is a hassle, they just work with mobile apps. These apps vary from "dreadful" (BP Pulse, really, just best avoided) to "really good" (PodPoint). Perhaps expecting an oil company to make good EV charging infrastructure is foolish.
The ideal outcome I would see for EV charging is it being an extension of your home electricity bill. The electrons are all the same after all. Just pay the service fee for the charger (per kWh or maybe, for DC charging, a fixed fee) and you get whatever rate your supplier negotiated for your usage. And the service fees should be fixed to some reasonable rate covering normal wear and tear of the charging equipment.
--- End quote ---
Excellent. I'll charge my car from my neighbour's charging point.
tggzzz:
--- Quote from: Marco on February 16, 2023, 11:20:42 pm ---
--- Quote from: tggzzz on February 16, 2023, 09:54:46 pm ---A charger must have the ability to read a payment device
--- End quote ---
At the point you're filling the entire country with chargers, it's far cheaper to just give people without a mobile phone one with a free sim, which can only be used to access a payment portal. App can have a bluetooth mode with an in-app reserve for when mobile data is down.
Regardless of any other aspect of the design, it will massively simplify the charger.
--- Quote ---Numbers please, e.g. voltages, currents, components, x/y/z dimensions.
--- End quote ---
Papers for existing prototype systems you can look up yourself.
--- End quote ---
It is your assertion, so presumably you have knowledge of the existing literature and products. Demonstrate that knowledge.
--- Quote ---Lets say a 4 plate system with plates 10x10cm. Then with 2 mm of 100x relative permittivity insulator the series capacitance would be around 2 nF. At 100 kHz that's an impedance of 5k. Lets assume simple impedance matched resistive load to get some ballpark figure, 1800V RMS required for 3 kW. Ballpark doable with a high permittivity insulator, without it not so much.
--- End quote ---
1.8kV near water (and in water when something fractures) is not something to leave lying in pavements. Especially if there is only a thin shatterable ceramic between people and the electrode.
At 100kHz/3kW there will be significant conversion inefficiencies from 50Hz (or DC). Just when you need water to cool such a converter, there will be a drought.
The difference between theory and practice is that in theory there is no difference, whereas in practice there is.
So, let's see the specs of the prototypes, and how well they performed outside the lab.
tggzzz:
--- Quote from: Marco on February 16, 2023, 11:45:13 pm ---It's not for convenience, it's to be able to put the charging connector on the curb and take up no room.
I'm not saying it's _the_ solution, I'm just saying in high density older European towns every solution to curb side charging has a ton of problems. The simple solution of just putting a charging pole every 6 meters will not work, not because of material cost but simply because it will make the street completely unusable. Every not simple solution is pretty far out there.
PS. all the pop up charger test runs don't seem to have UI either, so presumably all app based. But even popup chargers will take up a ton of extra space on the curb, unless there's so many of them they can pop up in between cars.
--- End quote ---
I'm glad someone acknowledges the physical impracticality of solutions dreamed up by others :)
If something pops up between cars, then sooner rather than later it either won't pop up or will pop up under cars!
tggzzz:
--- Quote from: tom66 on February 16, 2023, 10:07:12 pm ---
--- Quote from: tggzzz on February 16, 2023, 04:58:55 pm ---Zero surprise here! I only mentioned a (very) few places I could think of that I had been to :)
tom66 lists his location as "Cambridgeshire". Having lived there I would characterise it as
* a few small old bits
* lots of new bits
* lots of space, even in the old bits
* bloody boring, except for Ely and Cambridge centresIn other words it does not represent typical UK townscapes.
Given that, it isn't surprising if tom66 (and some people from the US on other fora) don't understand the impracticalities of their vision in "other places". Dismissing other people's completely valid experiences of "other places" does not reflect well on them or their position.
--- End quote ---
tom66 spent most of his student life in Leeds and used to park on a terraced street near Headingley Stadium with a small car. (Match days were not fun - do not move your car, you will not be able to park again.) tom66 also grew up in Hampshire in a small village with mostly street parking. Currently I do have a driveway (it was a non-negotiable requirement when buying the house) but probably not enough space for a second car without remodelling the drive somewhat so when we do have two electric cars we will just alternate charging requirements between these cars. The street I currently live on is alike many in semi-urban England - a mix of street parking and driveways, representative of the "25% of people*" not having access to off street parking. I look at my street as being pretty representative of most, a mix of detached, semi-detached, terraced and bungalows, mostly built before the 1950's before cars were very popular, but actually not that difficult to serve for charging requirements.
I do not currently live in Cambridgeshire, I moved to Northamptonshire six months ago. I would describe Northamptonshire as one of the most 'normal' counties I have lived in. It very much just looks like England.
--- End quote ---
In that case I find it remarkable (but not surprising) that you propose schemes that aren't practical in places that are familiar to you.
--- Quote ---I do not see street charging for EVs as unsolvable but like many problems it will need solutions appropriate to the area. Pavement gulleys (and sure, let's fine people who leave their cables out, I'm absolutely okay with that, but let's also fine people who park unnecessarily on the footway, too),
--- End quote ---
That's a fail right there. If the police and courts don't have the time to fine people that obstruct pavements, then why do think they will have time to fine people that leave trip/grounding hazards across pavements?!
Wake up and smell the coffee!
--- Quote ---pop up chargers, small posts, lamppost charging. and for those who have it, charging at home. Nothing about this is impractical, especially given there's at least 10-15 years before EVs become even a significant proportion of total vehicles on the road, and if you look at bigger cities the solutions are already appearing.
--- End quote ---
The impracticalities have been stated, and some others on this forum recognise them. Horses, water, drink.
--- Quote ---I'm also not sure exactly what your proposed alternative *is*, if your assumption is EVs cannot work for the vast majority due to charging headaches. We cannot continue to burn petrol, because climate change is a thing, ...
--- End quote ---
And there's the failure of your critical thinking analysis.
You incorrectly presume I don't support EVs.
You incorrectly presume I have a solution to intractable problems.
And you want me to respond to strawman arguments. Not going to happen.
--- Quote ---most people do depend on their car so public transport alone won't pick up the slack, so we do have to figure this out. So, what, do you want to see ...
--- End quote ---
What do I want to see?...
Like MacKay, I don't care which solutions are adopted, provided they add up and work in practice.
I get sick and tired of people thinking (I use that term loosely) that because the easy 10% can be cherry-picked, then that means the remaining 90% is solvable.
I also get sick and tired of people finding it acceptable to leave 10% (?25%?, whatever) of people severely disadvantaged. I know "I'm all right Jack" libertarianism is fashionable, but I find it loathesome.
--- Quote ---*25% is better than the earlier 50% figure I'd quoted from the AA, but they were probably not including anything but driveways in their estimation. Driveways are the easiest problem to solve for EV charging, but off-road parking in a shared lot is probably the second easiest, though requires more negotiation between parties (LA, landlord/land owner/etc.)
--- End quote ---
Off-road parking is not a problem w.r.t. installing chargers - it is low-hanging fruit that will be cherry-picked.
Powering it is less easy, e.g. in West London where the grid infrastructure is already insufficient for building new housing developments. Upgrading that distributed grid infrastructure is a major challenge, very expensive and very disruptive.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version