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This sounds like nonsense. EVs coast just fine and have a neutral "gear". They can be towed the same way.

Anything that applies to EVs would also apply to ICEs with automatic gears and electronic parking brakes etc.
 

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This sounds like nonsense. EVs coast just fine and have a neutral "gear". They can be towed the same way.

Anything that applies to EVs would also apply to ICEs with automatic gears and electronic parking brakes etc.
Um, no. Neutral in an electric car is just a regen setting (i.e. =0%). It does not physically disconnect the motors like a manual or automatic gearbox does.

If you tow.an electric car the motors still have to dump energy somewhere.

So yes, I agree that EV are a hazard (as are normal cars which breakdown) and that different procedures need to be understood and planned for when recovering them, especially on smart motorways.

The issue is this article suggests that EV are a greater hazard. They're not. Just a different one.
 

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Um, no. Neutral in an electric car is just a regen setting (i.e. =0%). It does not physically disconnect the motors like a manual or automatic gearbox does.
Correct, the motor is permanently engaged with the wheels in an EV. However that doesn't mean it can't coast. When you put an EV into neutral while in motion (or set regen to 0 on some models) the car will coast perfectly well, better than an ICE, despite the motor being connected because parasitic friction is vanishingly low.
If you tow.an electric car the motors still have to dump energy somewhere.
Not true. EV's use 3 phase electric motors, when they are spun by coasting they generate 3 phase AC voltage. However if this voltage doesn't go anywhere (is isolated, eg no current is drawn from the motor) no power is generated. This is what happens when the car is in neutral as well.
So yes, I agree that EV are a hazard (as are normal cars which breakdown) and that different procedures need to be understood and planned for when recovering them, especially on smart motorways.

The issue is this article suggests that EV are a greater hazard. They're not. Just a different one.
No, the claims made in the article that electric cars inherently "stop very suddenly" when they "cease to function" is utter bollocks. They're perfectly capable of coasting in neutral. And what does cease to function mean ? Run out of charge ? Or an actual failure of the drivetrain ?

As far as towing goes, the restrictions on towing some EV's are very arbitrary, a bit like restrictions on towing with an EV. For example Nissan says you shouldn't tow a Leaf with its driven wheels on the ground, and yet my Peugeot Ion manual says you can tow it for up to 50 miles at 50mph with the driven wheels on the ground.

Why ? They both use the same style of permanent magnet motor and similar drive inverter designs...the difference is that Nissan is covering their arse in the very unlikely event that it does cause a problem.

In any case such restrictions don't apply to towing the car with the driven wheels off the ground. Typically cars would be towed with the front wheels off the ground anyway, which means it's not a problem for a FWD EV.
 

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This story has a number of inaccuracies. For a start, the Government haven’t “admitted” anything about EVs’ behaviour.

It was Baroness Lady Randerson who brought the matter up during a debate on Smart Motorways in the House of Lords. She said:

“Finally, I raise the issue of electric vehicles. When an electric vehicle ceases to function, it stops; it does not coast in the way that other vehicles do. Smart motorways are supposed to be the future, but the future is electric. Those vehicles stop very suddenly. They also cannot be towed; they have to be put on a low-loader, which is a much more complex and longer process that will put rescue teams in greater danger. So can we have special consideration for how these new motorway layouts will operate when there are lots of electric vehicles on the road?“

Baroness Vere of Norbiton, Parliamentary Under Secretary of State, Dept of Transport said simply she’d look into her colleague’s claims.

Baroness Vere vehemently supports Smart Motorways, despite admitting openly that people are being killed on them due to the lack of a hard shoulder, claiming in defence that drivers who’ve stopped on them in an emergency need “educating”.

Her concern regarding the claims around EVs were made in the context of removing obstacles that might hinder the path for the further expansion of Smart Motorways, the DoT’s current plan.

However, ICEs behave in a similar way when they breakdown only coasting a few metres before stopping.

As well meaning as Baroness Lady Randerson’s comments are in opposition to Smart Motorways, the inference of her comment seems to be that EVs stop abruptly the second they go wrong, which simply isn’t the case.

More poor journalism. One would think the Political Editor of a broadsheet would consult his Motoring Editor before writing a story about cars and roads. The result of his not so doing is a story that inaccurately bashes EVs rather than the bigger story he could’ve written about how the Under Secretary of State for the DfT is hell bent on building more motorways with no emergency lanes despite openly admitting people are being frightened, seriously injured and killed on them.
 

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Correct, the motor is permanently engaged with the wheels in an EV. However that doesn't mean it can't coast. When you put an EV into neutral while in motion (or set regen to 0 on some models) the car will coast perfectly well, better than an ICE, despite the motor being connected because parasitic friction is vanishingly low.
I agree you can coast (regen = 0) but how many of use drive around with regen at 0? Unlike an ICE, most of us drive around with at least some regen active, and so how many have the immediate response to shift to neutral if they detect a loss of drive power? In a ICE your engine braking in 5/6 gear is low enough to not be an issue.

DBMandrake said:
However if this voltage doesn't go anywhere (is isolated, eg no current is drawn from the motor) no power is generated. This is what happens when the car is in neutral as well.
Hence why I said energy, not electricity. Don't conflate the two. By not drawing electricity from the motors you are instead building up thermal energy.

DBMandrake said:
For example Nissan says you shouldn't tow a Leaf with its driven wheels on the ground, and yet my Peugeot Ion manual says you can tow it for up to 50 miles at 50mph with the driven wheels on the ground.
That's not arbitrary. They're completely different vehicles with different cooling and integration. If you said a 208 and Corsa had different instructions that would be arbitrary.

DBMandrake said:
In any case such restrictions don't apply to towing the car with the driven wheels off the ground. Typically cars would be towed with the front wheels off the ground anyway, which means it's not a problem for a FWD EV.
Not by a Highways Agency patrol. They'd use a fixed bar and tow to nearest refuge are. As you can imagine, that's a lot easier than calling a flatbed.

My point still stands, EV are a different hazard to highways safety, just like they are to fire safety, but by no means a greater hazard. You have to acknowledge these differences and plan accordingly.
 

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To mitigate against the effect of EV drivers running out of charge unexpectedly, it could be possible to install a type 2 AC charge point in each refuge layby on the smart motorway.

These could be normally disconnected, but remotely activateable from the control centres for the situations where an EV user has run out of charge due to traffic delays etc and give them enough charge to get to the next MSA.
 

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Thanks DBMandrake for pointing out the inaccuracies in that article. It would be a great advance for society if those short of a critical ability could cease to quote that Tory rag, yes you OP.
 

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Seems to me the answer is a great big "depends"...
Drive/neutral selection is electronic, so some failure modes would also disable the ability to engage neutral manually. The avarage driver would probably not be sufficiently on the ball to select neutral in time in the event of a sudden failure anyway.
Also things like failure of power semiconductors in the inverter could cause a permanent load on the motor causing rapid deceleration.
HOWEVER although there are a some plausible failure modes that would result in a dead stop ( probably no more than with an ICE) , the fact that most of these failures are in electronics, which are inherently way more reliable than the mechanical parts of ICE cars, means that any such failures are far less likely.
I don't know if there are any stats on EV failure modes on the road, but I don't recall reading about any at all in the various EV forums I browse.
 

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If you tow.an electric car the motors still have to dump energy somewhere.
Only if the motor or control electronics have failed to a state where there is a load on the motor.
An open-circuit motor can freewheel just fine with no need to dump energy. I believe at least some EV motors use an electrically excited field rather than permanent magnets, and this type of motor would also freewheel regardless of any electrical failure if the field supply is disconnected.
 

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Pathetic article, there is a lot more that can ‘fail’ on an ICE vehicle than an EV.

What if a cambelt snaps while bombing along in the inside lane of a motorway as just one example? Some pretty severe ‘engine braking’ gonna happen there until you drop the clutch,easily cause a pile up.
The problem here is the Smart motorway IMHO they are just damn dangerous, the hard shoulder was invented for very good reason.
 

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"Government admits" - sounds like a Daily Mash article header.. I saw that this morning on my phone but couldn't read the whole article, but my, isn't the Telegraph sounding more like the Mail and Express every day. Soon they'll be having BLOCK letters in their headlines.
 

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According to the visible part of an article on the Government's house rag "electric cars hazard motorways government admits"
If for understandable reasons you don't want to read the article it is based around a house of lords government spokesman commenting during a debate that "she was "astonished" to discover that electric vehicles tend to "stop very suddenly" when they cease to function, rather than coasting like conventional cars, and that they can take longer to be removed from motorways."
Clearly she was put up to this by someone as whilst clearly well educated has no involvement with engineering or electric vehicles.
We perhaps have to accept that there is some truth behind the second point of EVs needing suspended tows for significant distances, but it's not the case between the originally promised emergency refuges on "smart" motorways. And where does the "stop very suddenly" bit come from? EVs coast like other vehicles.
Perhaps the fact that the minister got her peerage from Cameron for leading Project Fear and that she formerly led the Girl's School Association and was a banker in the financial crash shows her calibre.
 

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First statements is pretty much true, once the power is lost, most if not all EVs will come very quickly to a complete halt and I'm not sure if the brake lights turn on. They will come to a complete stop quickly because the gear is engaged. Would be an idea if the manufacturers make a 10-15 seconds countdown before the car actually shuts down completely.

The towing prohibition is not valid only for EVs, but almost any high-value car is prohibited to be towed. Flatbeds are required generally nowadays for many cars, not only for EVs, so that's a bit of a misleading remark.
 

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She has clearly got to the heart of the problem without quite realising it, any vehicle stopping on a motorway without a hard shoulder is a problem, especially when drivers ignore lane closed signs and speed restrictions.

You have to wonder if a directorship of an oil company is in the pipeline.
 

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Surely this is an excellent argument for mandatory charge points in sufficient numbers and in working condition at MSAs to meet the needs of ev vehicles.
Any good risk assessment involves a risk reduction plan. So in a risk assessment of smart motorways the provision of charge points at MSAs that work and are available in adequate numbers will be mandated.
 
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