Electric Cars.

[Learner]

  Motorway services providing  marshalls because of '"charge rage" according to the telegraph and a few others😁

Edited October 1, 2023 by Learner

[Ron Gray]

49 minutes ago, FlyinFlynn said:

As you slow down regen must surely become less effective, do you never apply your brakes to come to a complete stop? 

Speaking from my own experience, regen braking is effective until about 1 mph then the brake pedal is applied to come to a full stop. In iPedal it will automatically stop the car even if the brake pedal isn't used! There is even a brake disc cleaning function so I don't have to worry about the discs.

[Tim Kearsley]

In the Tesla regen is very marked and brings you to a complete stop. I've always tended to brake well in advance, so it wasn't that much of a change in "style" for me, but "one pedal" driving definitely takes a little bit of getting used to.  On the rare occasions that I charge the car to 100% regen is missing for a few miles (you can't put charge in a full battery!) and that catches me out when I suddenly realise I've got to use the brake pedal!

[Martin Harris - Moderator]

One thing that's struck me is the cleanliness of the front wheels, suggesting little brake pad wear.  The MG5 doesn't give true "one pedal" driving but I normally have regen at maximum and feather the brakes as it slows.

[MattyB]

3 hours ago, FlyinFlynn said:

It's a brave new world!.... Are you saying no one will ever drive like that after driving an EV?  I'm sure not everyone will take this on board and continue to drive in that manner.

No, I’m saying that everyone I know who owns an EV or hybrid with regenerative braking makes massive use of it when they drive their car. This is because a) it’s fun, b) it makes driving super simple and relaxing, and c) it maximises the range and efficiency of the car, giving you extra miles for free. Would it change your driving style permanently in all vehicles? I’ve no idea, though I did nearly overshoot the first junction of the journey in my wife’s manual Jazz the other day after I forgot it didn’t have regen!

 

3 hours ago, FlyinFlynn said:

As you slow down regen must surely become less effective, do you never apply your brakes to come to a complete stop? 

Different cars are set up differently. Mine has relatively strong regen as std in B mode, but if you just breathe on the brake pedal (not actually enough to engage the brakes, just light up the brake lights) it engages an even stronger level of regen that will decelerate the car pretty quickly. I don’t generally use this though, as with a bit of planning taking your foot out at the right point with the std level of regen is enough.
 

As you go slower the amount of regen does drop away a little, but it’s well capable of bringing you down to 1-2mph, the std “auto creep” speed. At that point all it takes is a tiny breath on the brake pedal to bring the car to a full stop if you can’t roll the junction due to other traffic. It took me ~20 miles or so to really optimise the technique, but I can now drive it on one pedal 99% of the time whether in full EV or hybrid mode.

 

PS - Although my Passat is not a truly 1-pedal machine, I have driven a Leaf, and in e-pedal mode the regen on that will absolutely bring you to a full halt, and pretty quickly too. I found it so strong it was initially a bit tricky to drive smoothly, but I’m sure you’d get the hang of it in 20-30 miles or so. It certainly seemed very efficient (>5miles/kWh for the test drive I took on a mixture of roads).

 

Edited October 1, 2023 by MattyB

[MattyB]

2 hours ago, Martin Harris - Moderator said:

One thing that's struck me is the cleanliness of the front wheels, suggesting little brake pad wear.  The MG5 doesn't give true "one pedal" driving but I normally have regen at maximum and feather the brakes as it slows.

This is literally the very best feature of driving an EV IMO. I’ve done just under 1k so far, and the alloys still look super clean with none of that horrible brake dust hanging in every nook and cranny. Cleaning the wheels on the car used to be my least favourite job, so I didn’t do it that often which meant my alloys on the old car were in a pretty bad way and would have cost a lot to put right…The wheels on this car should never suffer that fate!

 

Edited October 1, 2023 by MattyB

[Martin Harris - Moderator]

1 hour ago, MattyB said:

No, I’m saying that everyone I know who owns an EV or hybrid with regenerative braking makes massive use of it when they drive their car. This is because a) it’s fun, b) it makes driving super simple and relaxing, and c) it maximises the range and efficiency of the car, giving you extra miles for free. Would it change your driving style permanently in all vehicles? I’ve no idea, though I did nearly overshoot the first junction of the journey in my wife’s manual Jazz the other day after I forgot it didn’t have regen!

 

Different cars are set up differently. Mine has relatively strong regen as std in B mode, but if you just breathe on the brake pedal (not actually enough to engage the brakes, just light up the brake lights) it engages an even stronger level of regen that will decelerate the car pretty quickly. I don’t generally use this though, as with a bit of planning taking your foot out at the right point with the std level of regen is enough.
 

As you go slower the amount of regen does drop away a little, but it’s well capable of bringing you down to 1-2mph, the std “auto creep” speed. At that point all it takes is a tiny breath on the brake pedal to bring the car to a full stop if you can’t roll the junction due to other traffic. It took me ~20 miles or so to really optimise the technique, but I can now drive it on one pedal 99% of the time whether in full EV or hybrid mode.

 

PS - Although my Passat is not a truly 1-pedal machine, I have driven a Leaf, and in e-pedal mode the regen on that will absolutely bring you to a full halt, and pretty quickly too. I found it so strong it was initially a bit tricky to drive smoothly, but I’m sure you’d get the hang of it in 20-30 miles or so. It certainly seemed very efficient (>5miles/kWh for the test drive I took on a mixture of roads).

 

Similar to my experience - for doubters out there, think of the effectiveness of prop brakes on our ESCs…

 

Similarly, coaches have used electric retarders for decades, working on similar principles. 

[Paul De Tourtoulon]

I don't think that you can generalise, I drive my V 8 like a hearse, my 308 diesel like a lorry and I drove the ev Fiat 500 the other day, and I was a real hooligan,

[Frank Skilbeck]

Replaced our 2004 Colt with a 71 Mini EV just a few weeks ago, cost an additional £40 for the remaining 7 months, not too bad considering the performance and cost increase. My 2018 320D Touring had gone up by 40% earlier in the year. 

 

Mini has full stop regen braking, hardly use the friction brakes, note the brake lights come on with the regen braking. Regen braking is fully proportional great for descents.

[John Lee]

You can see from this report from my phone app that I recover about 62% of the energy used with regeneration:

 

 

12 hours ago, Learner said:

  Motorway services providing  marshalls because of '"charge rage" according to the telegraph and a few others😁

 

Of no concern to me. In 6 years of driving PHEV & pure EV's I've never charged at a motorway services. Nor did I fill up with petrol or diesel at those places in the preceding years.

 

With a little forethought there are better options.

[Gary Manuel]

13 hours ago, Ron Gray said:

Being a new EV owner regen braking has meant having to slightly adjust my driving style but, like Tim, I now hardly use the brakes, it’s brilliant. Not too sure about iPedal though.

iPedal is permanently on for me. Just takes a bit of getting used to.

[Learner]

25 minutes ago, John Lee said:

 

 

 

 

 

Of no concern to me. In 6 years of driving PHEV & pure EV's I've never charged at a motorway services. Nor did I fill up with petrol or diesel at those places in the preceding years.

 

With a little forethought there are better options.

At the moment while theres a 30 to 1 ic to ev ratio there are choices if you have the time and are prepared to look. Maybe harder in the future as that figure reverses.

[Outrunner]

50 minutes ago, Gary Manuel said:

iPedal is permanently on for me. Just takes a bit of getting used to.

 

What's an iPedal?

[Gary Manuel]

15 minutes ago, Outrunner said:

 

What's an iPedal?

Press pedal to accelerate, ease foot of pedal to use regenerative braking. It can bring the car to a complete stop and hold it on a hill. If you drive carefully, there is no need to use the footbrake unless you need extra braking force.

[Paul De Tourtoulon]

1 minute ago, Gary Manuel said:

Press pedal to accelerate, ease foot of pedal to use regenerative braking.

Useful for making your passenger sick,,,

[Gary Manuel]

25 minutes ago, Paul De Tourtoulon said:

Useful for making your passenger sick,,,

It's very smooth actually, but I suppose if you really wanted to.......

[Erfolg]

I appreciate that regenerative braking is a good feature. Yet, it is not essential for energy efficiency. In my case I drive a diesel car, it averages 55 mpg. I am still using the original brake pads and tyres at 55, 000 miles. Driving style is important, particularly with respect to tyre particulate production, now the latest plague.

 

I have just read that "Copart" that 50% of electric vehicles of low mileage EVs, exhibit battery damage. It is not clear why, other than these are low damaged vehicles. the ABI (association of British Insurers) has written that at present it is costing 33% more to repair EVs compared to IC vehicles. It seem that EV design has some way to go. 

 

I have also read that half the value of a EV is the battery. I am not convinced that many EVs are not overpriced. It suggests that a a typical £40,000 vehicle (often a low cost for an EV), that it cost £20,000 to build the rest of it. Then there is the EU suggestion that Chinese manufactures are dumping EVs as they are often much cheaper. Hmm who is doing what?

 

The changing the sales point of IC vehicles from 2030 to 2035 is probably a good one for the UK. It appears that the EU saw the UK as where the money would come from due to a constrained market, to fund the change to manufacture of EVs. All whilst the European IC engine, gearbox etc plants could be run to the end of their natural production life. Now that cash cow is not as easily exploited. Particularly as the data on pollution of the latest IC vehicles is pretty good, even compared to whole life energy audits. 

 

Of significance to us modellers (those with Balsa wood, egg box, infill) in the ImechE mag, there was a article indicating that the viable life of Wind Turbine blades is as calculated or lower (limited by fracture mechanics, of composite, crack propagation). Apparently the Resin matrix is a significant disposal issue.

 

 

Edited October 2, 2023 by Erfolg

[Nigel R]

15 minutes ago, Erfolg said:

It suggests that a a typical £40,000 vehicle (often a low cost for an EV)

 

Note, MG4 hatch is £27k.

 

It's about the cheapest electric hatch, mind. Brand snobs will need to pay near £40k for a hatch.

 

[Paul De Tourtoulon]

Our local post office sorting centre has a few electric delivery vans, I only hope that like their petrol vans that they are sold off on the cheap, that will be a good

car to take my toys to the playing field and our ( dare I say it ) electric bikes.

[Frank Skilbeck]

1 hour ago, Erfolg said:

I appreciate that regenerative braking is a good feature. Yet, it is not essential for energy efficiency. In my case I drive a diesel car, it averages 55 mpg. I am still using the original brake pads and tyres at 55, 000 miles. Driving style is important, particularly with respect to tyre particulate production, now the latest plague.

 

55 mpg on a diesel is roughly around 1.2 miles per kwh based on the energy a gallon of diesel holds.

 

Yes I managed to get over 72,000 miles out of a set of brake pads on my 520D, but even if you keep off the brakes on an IC car the coasting and compressing air still turns kinetic energy into heat, where as an EV (or hybrid) converts some of it back into fuel, so it is a substantial factor in energy efficiency especially in a start/stop environment, unless that is you put your car into neutral every time you slow down and let it coast to a stop that way. (although many regular ICE cars now charge the 12v battery when you slow down, but the effect on overall efficiency is negligible)

[John Lee]

As well as stop-start driving there are substantial regenerative savings when operating in an undulating environment, you use energy in the climb but regain much of it in the decent. It always tickles me on the return journey after slope soaring that upon descending from the mountain & rejoining the main road I have a couple more miles of range than that I started with.

[Erfolg]

I do not dispute at all that regenerative braking makes sense. 

 

Although I have noted that when coasting (whilst in gear) the mpg (on the mpg indicator) goes to infinity (obviously not true, breaking  all the laws of physics). I also note that BMW recommend that you should coast towards a stop, rather than brake. I have also read that it is more efficient to coast in gear than out of gear. I must admit, I do not see the logic.

 

I vaguely remember that in physics or was it applied maths, when another student suggested that you should be able to infinitely coast from one hill to another, using that mgh=0.5mv^2. The tutor said the obvious fly in the ointment that not all hills and depressions are a true sinusoidal wave. Yet the real problem is that to many components of the real world model such as drag, friction, rotational losses and other factors are ignored, in these applied maths problems.

 

I have mentioned it previously that when returning home on a particular journey, it was raining hard and that my normal motorway 80 mpg had dropped to about 30 mpg. It surprise me that pumping water past the tyres was so costly.

 

I must admit, I have had some issues with Windmills. Where I live there are two Windmills (last year one lost it sails, getting national coverage), there was one more, in the immediate locality. I have pondered in the past, how would you model the economics of wind powered flour production versus then steam powered flour mills (now electric). At first thoughts it seems free energy would always win, yet has not.

 

For some years now I have thought, working out what works and why, is not always as obvious as it would first appear.

[Nigel R]

22 minutes ago, Erfolg said:

I have also read that it is more efficient to coast in gear than out of gear. I must admit, I do not see the logic.

 

The motion does the work of keeping the engine spinning, rather than using fuel to do so, obviously the balance of transmission losses and pumping losses vs fuel used at idle, is such that coasting in gear wins.

[john davidson 1]

Coasting in gear provides a braking effect ( greater or less depending on the gear, low gear equals more) try a four stoke motor bike. Coasting in neutral is probably frowned on because of less control?

[Frank Skilbeck]

Yes on a fuel injected IC car when you coast in gear no fuel is injected until the rpm drops to just above tickover rpm, so yes you get infinite mpg in that phase, but in an electric car you reverse the energy flow.

 

On my 320D automatic when you switch to eco mode it actually coasts in neutral until you touch the brakes then it engages the gearbox and then keeps it engaged (or use the flappy paddles), on the Mini EV you feather the throttle, hold it down a bit it coasts like an IC in neutral, lift off a bit more like an IC in gear, but with some recharge, come off completely and it's like moderate braking with more recharge. It was weird for the first day, now it's natural.