Author Topic: EV-based road transportation is not viable  (Read 73973 times)

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Offline vadTopic starter

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EV-based road transportation is not viable
« on: January 15, 2023, 04:48:07 am »
Battery-powered vehicles will not save us. Here is why by a mechanical engineer from Serbia:

https://youtu.be/k8CnlL8I4HE

He brings few interesting points: charging infrastructure is infeasible for many car owners (think the third world countries where urban population lives predominately in high density residential buildings), and CO2 emissions impact of EVs is comparable to impact of vehicles with internal combustion engine.

I agree with the author. ICE vehicles are not going anywhere any time soon. Not until global hydrocarbon reserves are depleted. Beyond that point, transportation industry will switch to alternative energy carriers. I doubt that lithium ion batteries will dominate as energy carriers by then. In my opinion, hydrogen infrastructure, where a gas station is replaced by a hydrogen station, is more practical.
 
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Offline Siwastaja

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Re: EV-based road transportation is not viable
« Reply #1 on: January 15, 2023, 07:24:14 am »
You are 10 years late with that criticism. It already happened, and it was viable after all. Sorry.
 
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Offline james_s

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Re: EV-based road transportation is not viable
« Reply #2 on: January 15, 2023, 07:48:16 am »
While it's true that ICE cars are not going anywhere any time soon, EVs have already shown to be practical for millions of people. I know at least half a dozen people that drive them, several have had them for quite a few years now.

It's always funny to me when I see someone predicting something will never work that has already been working for quite some time.
 

Offline MadScientist

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Re: EV-based road transportation is not viable
« Reply #3 on: January 15, 2023, 08:06:41 am »
Battery-powered vehicles will not save us. Here is why by a mechanical engineer from Serbia:

https://youtu.be/k8CnlL8I4HE

He brings few interesting points: charging infrastructure is infeasible for many car owners (think the third world countries where urban population lives predominately in high density residential buildings), and CO2 emissions impact of EVs is comparable to impact of vehicles with internal combustion engine.

I agree with the author. ICE vehicles are not going anywhere any time soon. Not until global hydrocarbon reserves are depleted. Beyond that point, transportation industry will switch to alternative energy carriers. I doubt that lithium ion batteries will dominate as energy carriers by then. In my opinion, hydrogen infrastructure, where a gas station is replaced by a hydrogen station, is more practical.

Hello you’re about 5 years too late millions of EVs on the road and more to come. Sure the steam engine will never catch on and the world only needs 7 computers !!!!
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Offline BravoV

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Re: EV-based road transportation is not viable
« Reply #4 on: January 15, 2023, 08:08:10 am »
You are 10 years late with that criticism. It already happened, and it was viable after all. Sorry.

Yep, the OP's knowledge and perspectives are way-way out dated.

Just watch this ... ( this video is made one year ago) ...


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Re: EV-based road transportation is not viable
« Reply #5 on: January 15, 2023, 08:54:12 am »
You are 10 years late with that criticism. It already happened, and it was viable after all. Sorry.
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Offline mikeselectricstuff

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Re: EV-based road transportation is not viable
« Reply #6 on: January 15, 2023, 09:24:32 am »
The viability of EVs is dependent on power infrastructure, but that can catch up.
There are plenty of solutions for people who can't charge at home - e.g. in the UK, in some areas every other lamppost on the street has a chargepoint built in
Last month in the UK EV;s outsold ICE cars, and there are more than a million on the road.   Also over 50% of electricity here is regularly coming from renewables, with only a tiny percentage of coal remaining.
In my opinion, hydrogen infrastructure, where a gas station is replaced by a hydrogen station, is more practical.
Hydrogen will never be viable outside of a few niche applications, it's just too inefficient.
Here's a good vid explaining why Hydrogen is not the answer

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Offline AVGresponding

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Re: EV-based road transportation is not viable
« Reply #8 on: January 15, 2023, 10:52:53 am »
The situation regarding the feasibility of EVs varies very much based upon where you live, your income, and what you use a vehicle for.

I work as an electrician for a metropolitan council in the UK. My journey to and from work is up and down steep hills, with significant quantities of tools and gear, as necessary. An electric vehicle capable of taking me to and from work is a long way outside my price range, and there is most definitely no charging infrastructure where I live (and no realistic possibility to add it, at this time), nor at the vast majority of places where I work.

As part of the clean air initiative the council are looking at changing all their vehicles to electric; this is proving to be a massive and costly undertaking, where, as an example, a new bin wagon costs around £180k for a euro 6 derv, and around £500k for an EV. Then you have the cost of the charger on top, another £50k.
For a fleet of, say for the sake of argument 50 bin wagons, this is a huge increase in cost, at a time when they are already running a deficit (and have been for years), and are facing further funding squeezes by central government.

And that is before we get to the capital investment part; so far that's just been periodic replacement and running cost increases. They've had an EV wagon on loan, to test it, and it's so far not been very well liked; it has a short run time, and because the electrical infrastructure at the depot can't handle it, the charger can't even fast charge. And that's just one truck.
I expect there are estimations going on as to the cost of upgrading the electrical infrastructure for all the depots where they will want to use them, and I know we are replacing all the boards at one of the depots pretty soon, but that will still only get them one charger running at low power at that depot. Why? Because the supply from the substations isn't big enough to do more, at any of the depots. So that means new mains from the substations, at a cost of probably at least £5m per depot, maybe more, and that's assuming spare capacity at the substations, which isn't a given.

Now, I'm not anti-EV, I'm not saying it can't be done, and I'm not saying it shouldn't be done. I am saying it's going to be bloody expensive, and it certainly isn't going to be finished by 2030.
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Offline tom66

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Re: EV-based road transportation is not viable
« Reply #9 on: January 15, 2023, 11:06:46 am »
It's certainly seeming pretty viable so far.

Though we do need to get better chargers - the problem isn't so much the speed as it is the reliability.

Maybe ~1% of petrol pumps are out of service at any one time, but the fraction of EV chargers out of service seems much greater, around 10%, and worse, they tend to take months to get fixed.  Often the EV chargers are one or two to a station, so a charger out of service reduces capacity considerably. 

If you have a driveway or off road parking and can install a charger, then barring a few odd cases like the guy who travels 300 miles every day (not my idea of fun), they're entirely viable vehicles to use as daily drivers.  For apartment blocks and on-street parking, more lamp-post chargers as Mike mentions, will be required, but I'd agree the infrastructure isn't there yet. 

On cost, new technologies are still very expensive.  But, the prices are already falling.  Brand new MG4 Electric with a 50kWh battery is about £25k.  That is pretty much the same price as a petrol Golf.

For those who buy used vehicles, I've been watching with interest how these are slowly dropping.  The Tesla Model 3 can now be had for under £30k, as can the ID.3 (VW's electric Golf).

Also, there's no ban on old fuel vehicles, I expect we will have them until well into the 2040's, but it is a good idea to stop selling new fuel powered vehicles (at least for passenger cars).
 

Offline mendip_discovery

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Re: EV-based road transportation is not viable
« Reply #10 on: January 15, 2023, 11:16:06 am »
The situation regarding the feasibility of EVs varies very much based upon where you live, your income, and what you use a vehicle for.

I work as an electrician for a metropolitan council in the UK. My journey to and from work is up and down steep hills, with significant quantities of tools and gear, as necessary. An electric vehicle capable of taking me to and from work is a long way outside my price range, and there is most definitely no charging infrastructure where I live (and no realistic possibility to add it, at this time), nor at the vast majority of places where I work.

As part of the clean air initiative the council are looking at changing all their vehicles to electric; this is proving to be a massive and costly undertaking, where, as an example, a new bin wagon costs around £180k for a euro 6 derv, and around £500k for an EV. Then you have the cost of the charger on top, another £50k.
For a fleet of, say for the sake of argument 50 bin wagons, this is a huge increase in cost, at a time when they are already running a deficit (and have been for years), and are facing further funding squeezes by central government.

And that is before we get to the capital investment part; so far that's just been periodic replacement and running cost increases. They've had an EV wagon on loan, to test it, and it's so far not been very well liked; it has a short run time, and because the electrical infrastructure at the depot can't handle it, the charger can't even fast charge. And that's just one truck.
I expect there are estimations going on as to the cost of upgrading the electrical infrastructure for all the depots where they will want to use them, and I know we are replacing all the boards at one of the depots pretty soon, but that will still only get them one charger running at low power at that depot. Why? Because the supply from the substations isn't big enough to do more, at any of the depots. So that means new mains from the substations, at a cost of probably at least £5m per depot, maybe more, and that's assuming spare capacity at the substations, which isn't a given.

Now, I'm not anti-EV, I'm not saying it can't be done, and I'm not saying it shouldn't be done. I am saying it's going to be bloody expensive, and it certainly isn't going to be finished by 2030.


I agree.

We have had a EV visit our village since I was a kid, they got phased out for Derv as costs for replacing the EV was silly and the issues around making noise at 4am were gradually ignored.

As I said elsewhere I can't have an EV yet due to charging solutions. So I have a nice 20yr old vehicle for daily use, I can't go into 2 of the larger cities anymore (Bath & Bristol) so they won't get my custom. Though they will bend the rules when they need the use of my 20yr old vehicle.

I suspect we will need to look at upgrading for work but I can't see my MD being OK for me to stop halfway to a job to charge up the EV van for 1hr or so. There are many problems to solve and I don't think politicians know this, they are like the CEO that just says solve this by next week or I want 2 red lines but using blue ink.

With my Tin-foil hat on, so far to me, it looks like the times of old are coming back. Only the wealthy will have transport, the poor can only use public transport and they must work in the local places.
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Offline AVGresponding

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Re: EV-based road transportation is not viable
« Reply #11 on: January 15, 2023, 11:29:21 am »
I probably shouldn't have mentioned 2030 as it's not really relevant to the points I'm trying to make.

I can't afford a usable electric car. I can barely afford to run my existing car. My daily cost me £1250 a little over 2 years ago, and that's the sort of budget I'm likely to be limited to when I need to get another. A new car of any description is simply out of the question, and would be for anyone else on the tools here. Good luck finding an EV for that money. As a council worker, I'm public sector, and like much of the public sector workforce, over the last 12 years or so, I've had a 25-30% real-terms pay cut. Yes, I have seen the figures; it's not an exaggeration.

The infrastructure isn't there. To get there, is going to be very expensive, and very disruptive (lots of roadworks, everywhere). Charging points in lamp-posts is a joke; if all of them get used at once, hell if even a significant proportion get used at once, it'll trip the local supply. Most of those lights are running on a supply that was designed to power 400W (at most, and usually a lot less) lamps, not 10kW chargers, and even though most have been "upgraded" to LED (another contentious issue, for a different thread), the spare capacity is either quite small, or not there at all, as they've been altered to account for lower power.

The reality is that the infrastructure in this country is a long way from being able to support a 100% EV transport system, and all I'm seeing (at least in terms of local city/town/village infrastructure) to move us in that direction is baby steps at best.
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Offline mendip_discovery

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Re: EV-based road transportation is not viable
« Reply #12 on: January 15, 2023, 11:30:23 am »
There are plenty of solutions for people who can't charge at home - e.g. in the UK, in some areas every other lamppost on the street has a chargepoint built in

I have an issue with this statement as it gets banded about by the EV fanboys to shut up anyone who says they can't charge up at home. It might work in some areas but its not a solution open to all.

We have lamposts here, they are all on the other side of the pavement so the cable would have to drape across the pavement. In the past 2 years, 2 new ones have been installed as prior to that 500m has been covered by 1 lamp post. Now that 500m has 3. So 3 lamposts are to charge 17 cars. So though this maybe a solution for some areas its going to be costly to upgrade in my area. The roads and pavements are not wide enough to accommodate it. Though if our parish council have anything to do with it they would much prefer to have the road cleared of cars for it makes it hard for them to drive the luxobarge they have though the village.
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Offline tom66

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Re: EV-based road transportation is not viable
« Reply #13 on: January 15, 2023, 01:02:34 pm »
I have an issue with this statement as it gets banded about by the EV fanboys to shut up anyone who says they can't charge up at home. It might work in some areas but its not a solution open to all.

We have lamposts here, they are all on the other side of the pavement so the cable would have to drape across the pavement. In the past 2 years, 2 new ones have been installed as prior to that 500m has been covered by 1 lamp post. Now that 500m has 3. So 3 lamposts are to charge 17 cars. So though this maybe a solution for some areas its going to be costly to upgrade in my area. The roads and pavements are not wide enough to accommodate it. Though if our parish council have anything to do with it they would much prefer to have the road cleared of cars for it makes it hard for them to drive the luxobarge they have though the village.

Lamp post charging is part of the solution but we'll probably need more than lamp posts, that's true.

As for tripping the local supply.  The majority of these lamp post chargers are 3-4kW.  No EV (in the EU/UK) charges over 7kW on single phase anyway.  Lamp posts typically hang off the street ring main, which usually has enough capacity to add charging to, they are not running on a dedicated street lamp feed (some exceptions apply - old switched feeds being the most common example.)  Some areas will need upgrades if they are right up at capacity limits, but this same ring main powers houses and businesses, so adding a few kW of load every ~30m doesn't sound impossible to me.  The big challenge is fast chargers that pull 50-100kW, those are going to need a lot more work to install.

Using averages here: a normal driver does about 9,000 miles per annum.  Round to 10k to be generous and assume 3.5 miles per kWh which is below the average economy for an EV.  So annually the consumption is about 2,900 kWh.  (That's actually about the same as a house, using Ofgem's median.)  So how many chargers do you need? How long does each car need to charge for?  If the cars get charged every six days (on average - 164 miles per charge) then they'd need 47kWh of charge, at 4.6kW (20A street charger) that's about 10 hours of charging.  So a street needs to accommodate about 10 hours per week of charging per vehicle.  If you say 12 hours per day are viable hours to park and find a space with a charger (9am - 9pm, people don't usually want to be hunting at 3am for a spot) then you'd need approximately 1 charger for every 6-7 vehicles. 

Looking at some streets in London which have this technology already installed, they are at around 1 in 20 vehicles.  So they have a way to go, but it's not as if you will need a charger for every possible space and need to handle 100kW per road in charging demand.

In terms of economics: if that charger is busy every day of the week for 10 hours and dispenses 46kWh per day, then at a 5p/kWh margin, it makes £800 a year.  That's probably enough to make back its costs pretty quickly - though the cost figures for the lamp post chargers aren't given it's hard to imagine that modifying an existing lamp column costs much more than about £3-4k.  Installing a new charger is probably the most expensive option but if a whole street is done over the course of a day or two then the per device cost can be quite reasonable. 
 

Offline AVGresponding

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Re: EV-based road transportation is not viable
« Reply #14 on: January 15, 2023, 01:32:09 pm »
I think you're wildly optimistic about how much spare capacity there is.

And once again, "miles" or "kilometres" is a completely meaningless way to express the charge in a battery. Miles on the flat? Miles uphill? What about ambient temperature, variations in the mass of the load?
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Offline tggzzz

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Re: EV-based road transportation is not viable
« Reply #15 on: January 15, 2023, 01:38:54 pm »
I have an issue with this statement as it gets banded about by the EV fanboys to shut up anyone who says they can't charge up at home. It might work in some areas but its not a solution open to all.

We have lamposts here, they are all on the other side of the pavement so the cable would have to drape across the pavement. In the past 2 years, 2 new ones have been installed as prior to that 500m has been covered by 1 lamp post. Now that 500m has 3. So 3 lamposts are to charge 17 cars. So though this maybe a solution for some areas its going to be costly to upgrade in my area.

Such areas include West London... "It was reported earlier this year that new housing developments in Hounslow, Ealing and Hillingdon would have to be paused due to strain on the electricity network, with no spare capacity for new connections until at least 2035." It looks like that has been overcome politically. Cough.
https://www.standard.co.uk/news/london/west-london-electricity-shortage-housing-hounslow-ealing-hillingdon-b1031501.html

Quote
As for tripping the local supply.  The majority of these lamp post chargers are 3-4kW.  No EV (in the EU/UK) charges over 7kW on single phase anyway.  Lamp posts typically hang off the street ring main, which usually has enough capacity to add charging to, they are not running on a dedicated street lamp feed (some exceptions apply - old switched feeds being the most common example.)  Some areas will need upgrades if they are right up at capacity limits, but this same ring main powers houses and businesses, so adding a few kW of load every ~30m doesn't sound impossible to me. 

For that to be believable you have to specify how many lamp posts are fed from the "street ring main" - whatever that might be.

A quick glance indicates that an LED streetlight consumes ~0.1kW peak power. Therefore adding a 7kW charger is a rather large increase in peak power consumption!

N.B. peak power consumption is the relevant measure, since multiple cars will need to be charged at the same time, e.g. overnight. Mean is as irrelevant as the mean output of wind farms w.r.t. "keeping the lights on". No, the wind isn't always blowing somewhere! As a rule of thumb and taking the UK's entire wind generating capacity into account, for ~1% of the time (i.e. 3 days/year) the wind power output will be ~1% of peak or 3% of mean.

And then, as you note...

Quote
The big challenge is fast chargers that pull 50-100kW, those are going to need a lot more work to install.
... except it is more than simple local installation work, it is the entire generation and grid infrastructure.
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Offline mendip_discovery

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Re: EV-based road transportation is not viable
« Reply #16 on: January 15, 2023, 03:23:20 pm »
tom66 you make a good argument but can you also redo the maths but this time including the chap who lives two doors up he owns a BMW and an Audi, every time he drives away he has to try his best to make his mark on the road. I expect if we did go electric he would hog the local charger.

I still hope that they might go for swappable batteries so you pull up and fit new charged battery and drive off. This would save a lot of issues around charging and would even out the issues around affordability as the batteries would be rented and allow the cars to be that bit cheaper and meaning the running gear could live on longer that the battery.

An EV currently is very expensive and my thoughts are by the time they are down to the <£5k they will be at 1/3 battery life and be close to the MOT saying the battery is unsafe and the car need to be scrapped. But I am open to the idea that they will get cheaper I just hope we don't have a period of purposeful obsolescence just to sell people a shiny new car.
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Offline mikeselectricstuff

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Re: EV-based road transportation is not viable
« Reply #17 on: January 15, 2023, 03:59:22 pm »
I think you're wildly optimistic about how much spare capacity there is.

And once again, "miles" or "kilometres" is a completely meaningless way to express the charge in a battery. Miles on the flat? Miles uphill? What about ambient temperature, variations in the mass of the load?

Not super-accurate, but certainlly a long way from "meaningless"
These factors can be avaraged to give a figure that is meaningful enough for most purposes. Flat vs. uphill makes little difference as much of what you spend going uphill comes back on the way down via regen braking.
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Online bdunham7

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Re: EV-based road transportation is not viable
« Reply #18 on: January 15, 2023, 04:04:53 pm »
You are 10 years late with that criticism. It already happened, and it was viable after all. Sorry.

You have to be careful to address the proper question.  I didn't watch the whole video, but enough to know that the question is not "will/do EVs work for some or even many people?", but rather "will EVs replace ICE-powered vehicles entirely (globally) in the near or foreseeable future".

The answer to the first is "yes, they work fine for me and many others".  I've had one for nearly a decade now.  The answer to the second is "no, not with technology that is currently available or forseeable in the near future".  I know plenty of people for whom EVs are not currently a viable option nor will they be under anything like current circumstances.
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Offline tggzzz

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Re: EV-based road transportation is not viable
« Reply #19 on: January 15, 2023, 04:12:38 pm »
I think you're wildly optimistic about how much spare capacity there is.

And once again, "miles" or "kilometres" is a completely meaningless way to express the charge in a battery. Miles on the flat? Miles uphill? What about ambient temperature, variations in the mass of the load?

Not super-accurate, but certainlly a long way from "meaningless"
These factors can be avaraged to give a figure that is meaningful enough for most purposes. Flat vs. uphill makes little difference as much of what you spend going uphill comes back on the way down via regen braking.

Can you push energy into the battery as fast as you can pull it out? If not then regen braking will only be that efficient for short durations (e.g. start stop in cities) or on gentle hills.

I wouldn't trust a Tesla salesman to give an answer. In my experience they can't even manage to turn on a screen demister, simply parrot the company line about "typical" range, and spout incoherent DoubleSpeak about whether or not Teslas are self-driving. I doubt other salesmen are any better.
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Offline mikeselectricstuff

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Re: EV-based road transportation is not viable
« Reply #20 on: January 15, 2023, 04:20:34 pm »

Can you push energy into the battery as fast as you can pull it out? If not then regen braking will only be that efficient for short durations (e.g. start stop in cities) or on gentle hills.

Generally speaking, mostly, minus conversion losses. The power is going through the same motor and inverter electronics. maximum DC charger rates are a similar order of magnitude to motor powers, e.g. on my Kona, max DC charge is 77kW and the motor is 150kW max.
I don't recall offhand the max I've seen it regen, but pretty sure it was well over 50kW
 Of course driving style is a factor - slam on the brakes too hard and the friction braking will take over, and there are aero & friction losses.
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Offline tom66

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Re: EV-based road transportation is not viable
« Reply #21 on: January 15, 2023, 05:03:43 pm »
Can you push energy into the battery as fast as you can pull it out? If not then regen braking will only be that efficient for short durations (e.g. start stop in cities) or on gentle hills.

I wouldn't trust a Tesla salesman to give an answer. In my experience they can't even manage to turn on a screen demister, simply parrot the company line about "typical" range, and spout incoherent DoubleSpeak about whether or not Teslas are self-driving. I doubt other salesmen are any better.

Regen braking on my PHEV, which has a much less efficient battery than a normal EV (because it's so small) is about 75% round trip efficiency.  That is, if I put 1kWh into climbing a hill, I get about 750Wh going back down it on the way home - that's for a hill on a country road at about 40 mph speed limit.

It's less efficient the faster you go, because air drag dominates.  Climbing up the M62 in West Yorkshire towards Manchester usually had the power meter pegged at about 40% (this is with the engine on, but it's measuring overall system power regardless.) Whereas coming down the hill, the engine usually can shut off, but the regen is usually around ~5% power.   So there is much more power going in than going out.  I found the e-Golf to be more efficient here (fully battery EV) as it had aero skirts and rims, but it was around 10%.  So not dramatic.

For how people are driving, 3.5 miles per kWh seems to be a reasonable fleet average.  If you live in a city, you're probably closer to 5 miles per kWh, whereas if you are on the motorway going 85 mph, you might only get 2.5 miles per kWh.   
« Last Edit: January 15, 2023, 05:05:21 pm by tom66 »
 

Offline nctnico

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Re: EV-based road transportation is not viable
« Reply #22 on: January 15, 2023, 05:12:40 pm »
There are plenty of solutions for people who can't charge at home - e.g. in the UK, in some areas every other lamppost on the street has a chargepoint built in

I have an issue with this statement as it gets banded about by the EV fanboys to shut up anyone who says they can't charge up at home. It might work in some areas but its not a solution open to all.
Agreed. Public charging is horribly expensive as well. I'm 80% sure my first non-ICE car will be powered by hydrogen because that is better suitable & cheaper for my use compared to BEV. But first long haul trucking needs to accellerate implementing hydrogen fueling stations. Long haul trucks typically have ranges from 1200km to 2500km on a single tank. There is no way to match that using batteries.
« Last Edit: January 15, 2023, 05:17:42 pm by nctnico »
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Offline tggzzz

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Re: EV-based road transportation is not viable
« Reply #23 on: January 15, 2023, 05:16:29 pm »

Can you push energy into the battery as fast as you can pull it out? If not then regen braking will only be that efficient for short durations (e.g. start stop in cities) or on gentle hills.

Generally speaking, mostly, minus conversion losses. The power is going through the same motor and inverter electronics. maximum DC charger rates are a similar order of magnitude to motor powers, e.g. on my Kona, max DC charge is 77kW and the motor is 150kW max.
I don't recall offhand the max I've seen it regen, but pretty sure it was well over 50kW
 Of course driving style is a factor - slam on the brakes too hard and the friction braking will take over, and there are aero & friction losses.

Well 77kW vs 150kW is a factor of 2, which is about what I would have guessed without doing any research. Hence I believe it :)

That may well be fine in the Fens, or Cambridge where people get off bikes to go over a hump-backed bridge over a railway and the "dale" in Borrowdale invites the observation "Contour? What contour".

It might be a limitation in the Pennines or lakes - or in any country where anything higher than 2000ft/650m would not be classed a "mountain".
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Offline tggzzz

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Re: EV-based road transportation is not viable
« Reply #24 on: January 15, 2023, 05:21:42 pm »
Can you push energy into the battery as fast as you can pull it out? If not then regen braking will only be that efficient for short durations (e.g. start stop in cities) or on gentle hills.

I wouldn't trust a Tesla salesman to give an answer. In my experience they can't even manage to turn on a screen demister, simply parrot the company line about "typical" range, and spout incoherent DoubleSpeak about whether or not Teslas are self-driving. I doubt other salesmen are any better.
...
Climbing up the M62 in West Yorkshire towards Manchester usually had the power meter pegged at about 40% (this is with the engine on, but it's measuring overall system power regardless.) Whereas coming down the hill, the engine usually can shut off, but the regen is usually around ~5% power.  ...

I presume that is the same speed up hill and down dale :)

What would the power meter show going at the same speed on the flat with zero wind?
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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