Electric cars

Martyn1981

AdrianC wrote: »

I think that article proves the point I've had shot down many times...

By finding points at which the grid runs conveniently close to the motorway, they've identified 50 places where 350kW chargers could be placed without major grid upgrading. There are currently nearly 90 motorway services on 2,200 miles of motorway - and that's half of the strategic road network, itself just under 3% of the total road network. They don't say how many chargers at each location. 350kW is 30A at 11kV. Per charger.

Oh, and the total cost for their "transmission action plan"? Half to one billion quid. The article doesn't link to anything about this plan, so we don't know if this is JUST for this project (£10-20m per site...? Not hard at all, if there don't happen to be pre-existing service areas at those 50 sites) or something bigger. And this will go "some way" to alleviating the concerns that we're regularly told in this thread simply don't exist outside of the minds of those who clearly have vested interests...

350kW will fully recharge a single 100kWh battery in 17min - theoretically... If by "fully", they're really talking about 80% charged, then 5min is the theoretical bare minimum for a nominal 36kWh battery. So if we look at 60-80kWh batteries in sensible-range EV cars, then we're looking at a throughput of about five cars per hour per charger, less once people have finished fannying about.

Happy to have a play if you want. So yesterday you suggested 0.2% of cars being EV's in your area, so let's go with that.

30,000,000 cars @ 0.2% = 60,000 cars

Let's assume 5% are being used at any one time for long distance driving and will need charging on router (probably too high a percentage, but 'wot the hell').

60,000 cars @ 5% = 3,000 cars

Now, if they can drive for 3 hrs, and need 12 mins to charge, then charging time is 12mins/192mins = 6.25%

3,000 cars @ 6.25% = 187 cars

assume 50% will be using other chargers / charging networks

187 cars @ 50% = 94 cars

spread over 50 charging stations = 1.9 charging points

These numbers may be wrong as I couldn't really bother doing them properly, but suggest to me that this rollout seems adequate, and will presumably grow/expand over time.

AdrianC

"Adequate" is damning with faint praise, isn't it? This is meant to be supporting a substantial change, after all...

And, no, a Tesla-style full-underbody battery is not even remotely like chassis construction. It's just a monocoque with an absolutely-non-structural battery strapped to the underside. Remember BetterPlace, or even this from five years ago?

Martyn1981

AdrianC wrote: »

"Adequate" is damning with faint praise, isn't it? This is meant to be supporting a substantial change, after all...

Why would you roll out more than adequate at any point in time?

AdrianC wrote: »

And, no, a Tesla-style full-underbody battery is not even remotely like chassis construction. It's just a monocoque with an absolutely-non-structural battery strapped to the underside. Remember BetterPlace, or even this from five years ago?

You still aren't answering the question. Almost all cars these days are monocoque's, so please explain why an EV having a 'stronger' floorpan with batts, and extra weight, makes it unsuitable for towing v's other cars?

If you want to go down the route of 'serious' towing, then obviously you want an EV that compares to a frame based vehicle, such as the Bolinger EV I mentioned earlier.

AdrianC

Where did you make "stronger" up from? The boot floor is fuller, not stronger, leaving little space for the towbar to mount. Very few manufacturers have developed EV-specific platforms, really only Tesla (and even they used their Mercedes partnership for much of the S and X underpinnings), due to the monumental cost of development of anything remotely competitive. Every other manufacturer is moving towards sharing modular platforms for very sound reasons.

BTW, are you American? Your enthusiasm for such antediluvian concepts as chassis, almost 85 years after the monocoque hit mainstream mass production (and especially referring to chassis as "frames") would suggest so.

Herzlos

Having batteries doesn't rule out towing, the Outlander PHEV is pretty good at it, albeit with only a 1500kg limit (same as most petrol SUVs, and big enough for most caravans):
https://www.practicalcaravan.com/reviews/tow-car/31402-mitsubishi-outlander-phev

Theoretically, with full torque from 0rpm, an electric motor should be much better for towing, if you have a way to mount the tow bar frame.

Tesla X can also tow, at 2100kg. So the problem isn't with EV's.

Sure, currently most of the smaller ones aren't rated for towing, due to type approval and the extra weight.

Give it a generation or 2 and there will be some solid, high range towing EV's available for the few people who only have a single vehicle and do a lot of towing.

AdrianC

Herzlos wrote: »

Having batteries doesn't rule out towing, the Outlander PHEV is pretty good at it, albeit with only a 1500kg limit (same as most petrol SUVs, and big enough for most caravans)

Yes, it's a lot easier to find the space for the batteries under a largeish SUV without such a trade-off on boot space, so less need to remodel the boot floor pressings.

Compare that towing limit to 2000kg for the diesel Outlander, though, or 2500kg for a DiscoSport.

Sure, currently most of the smaller ones aren't rated for towing, due to type approval and the extra weight.

Yup.

Herzlos

AdrianC wrote: »

Yes, it's a lot easier to find the space for the batteries under a largeish SUV without such a trade-off on boot space, so less need to remodel the boot floor pressings.

But not impossible, they just haven't decided to do so yet, because so few cars are used for towing.

Compare that towing limit to 2000kg for the diesel Outlander, though, or 2500kg for a DiscoSport.

Or 3500kg for a Pathfinder, or 1200kg on a Duster. Different things have different capacities.

If you only need to pull a small-medium caravan or trailer, 1500kg is usually plenty.

Sure, if you need to tow > 2000kg, there's currently no EV that can do so. But there's also very few diesels that can that aren't large SUVs or pickups.

I'm sure it won't be long before there's an electric Disco or Pickup with a huge capacity.

I can't find any stats on tow cars in the UK - any idea how many there are? Anecdotally, I reckon I see less than about 1 in 20 cars with a visible tow ball, maybe as low as 1 in 50. I don't really go looking though.

Gloomendoom

AdrianC wrote: »

BTW, are you American? Your enthusiasm for such antediluvian concepts as chassis, almost 85 years after the monocoque hit mainstream mass production (and especially referring to chassis as "frames") would suggest so.

In Martyn's defence, he is actually using the correct terms. All cars, even modern ones, have a chassis although it is usually integrated with the body and not bolted to a separate frame (or chassis frame to give its correct full term). Sub-frames are still commonly used and a halfway house between a body-on-frame and unibody (monocoque) construction.

Martyn1981

AdrianC wrote: »

Where did you make "stronger" up from? The boot floor is fuller, not stronger, leaving little space for the towbar to mount. Very few manufacturers have developed EV-specific platforms, really only Tesla (and even they used their Mercedes partnership for much of the S and X underpinnings), due to the monumental cost of development of anything remotely competitive. Every other manufacturer is moving towards sharing modular platforms for very sound reasons.

The skateboard chassis of EV's would suggest to me that they are stronger than a typical monocogue. But if you are saying 'only as strong' then that's still not an answer as to why you have/tried rule out EV's for towing. I'm just wondering if your statement had any truth to it, or was just negative spin, that's all?

AdrianC wrote: »

BTW, are you American? Your enthusiasm for such antediluvian concepts as chassis, almost 85 years after the monocoque hit mainstream mass production (and especially referring to chassis as "frames") would suggest so.

Seems like a diversion to me, perhaps to avoid answering the question.

But no, I'm not American, though my first car was an American import with a 400ci engine. The infamous 'screaming chicken' from the 'hood' is actually in front of me hanging on the wall at this moment.

BTW, before I restored it to trophy winning condition it actually had a tow bar fitted, though it (ironically) is one of the few cars I've owned or driven that I haven't used for towing.

So back to EV's battery position and weight making them unsuitable for towing .........

AdrianC

Herzlos wrote: »

Or 3500kg for a Pathfinder, or 1200kg on a Duster. Different things have different capacities.

Mmm. A DiscoSport is an Outlander rival, though, and I think comparing an Outlander with an Outlander is reasonably appropriate.

I'm sure it won't be long before there's an electric Disco or Pickup with a huge capacity.

3t tow capacity for a FFRR or RRS hybrid, compared to 3.5t for the non-hybrid.

I can't find any stats on tow cars in the UK - any idea how many there are?

I doubt you'll get better than a wild guess.

Anecdotally, I reckon I see less than about 1 in 20 cars with a visible tow ball, maybe as low as 1 in 50. I don't really go looking though.

That's probably not an unrealistic number, but don't forget that many towbars are removable and very subtle.