Is it just me?

[Mactech]

EVs turn stored electric energy into kinetic energy, then turns the kinetic energy back to stored electric energy when braking.

The energy loss is from kinetic and electric energy turning into heat. The heat is dissipatedvat from the tyres as result of friction with the road, from the car's exterior as result of wind resistance, from the electrical motors, and from the battery cooling system. This accounts for the energy losses when driving on level ground.

When driving uphill, some if the stored electric energy is converted to potential energy. When driving downhill, the potential energy is turned back into stored electric energy, again with losses resulting from heat dissipation.

Overall, an EV as a car is much more energy-efficient than a comparable ICE car, because there are far less losses resulting from heat dissipation.

However, the issue with the energy efficiency of EVs is in fact not with the car itself, but with the overall process of converting fuel to energy. The EV will see many losses even before the electricity reaches the battery. The higher efficiency of the car itself does not compensate fully for the losses between the power plant and the home or public charger.

In any event, EVs do not use the brake discs for braking, instead they brake using the resistance of the electromagnetic field inside the motor, which is a frictionless process (hence the greater efficiency).

Exactly!

 

[markjay]

I forgot to mention the electric consumers in the car, e.g. radio, wipers, lights, aircon, heating, electric windows etc. Plus, some cars have a battery heater to enable fast charging in cold climate. My car is actually equipped with a heat pump, that captures heat from the battery and uses it to heat the cabit in winter.

 

[TC350]

But the fact remains the grans driving style would be rewarded with much better fuel economy and/or EV range. But she’d be much later to the party than the common tea leaf!

I’m not convinced that the gran would get to the party long after the thief. It depends on the roads. If the gran planned every move well ahead on roads with lots of hazards that needed to be negotiated, she wouldn’t need to slow as much as the thief. Getting from A to B quickly doesn’t necessarily mean driving fast.

 

[markjay]

I’m not convinced that the gran would get to the party long after the thief. It depends on the roads. If the gran planned every move well ahead on roads with lots of hazards that needed to be negotiated, she wouldn’t need to slow as much as the thief. Getting from A to B quickly doesn’t necessarily mean driving fast.

True. For all we know, the gran might have been a Road Rally ace driver in her youth....

 

[HappytalkAgain]

Getting from A to B quickly doesn’t necessarily mean driving fast.

Would you consider a career on an F1 Pit wall?

 

[Bobby Dazzler]

True. For all we know, the gran might have been a Road Rally ace driver in her youth....

I did some circuit driving with Bron Burrell at Silverstone a few years ago. If she was the gran in question then even five decades later you’d need to be handy at the wheel to beat her in a road race. She’s not lost it, and he talent hasn’t faded one but. Her weapon of choice was an E 63 S AMG.

 

[TC350]

Would you consider a career on an F1 Pit wall?

You may have heard of a Scottish guy who wasn’t too shabby at F1 and said, "Good driving for me is smooth driving,"

JACKIE STEWART SHOWS WHY GREAT DRIVERS ARE SMOOTH DRIVERS

There are many ways of insulting people, says former championship race car driver Jackie Stewart, and one of the surest is to tell them they are bad drivers. ``They won't believe you,'' he said. ``It's tough for people to admit they don't do it right.''

www.deseret.com

 

[HappytalkAgain]

You may have heard of a Scottish guy who wasn’t too shabby at F1 and said, "Good driving for me is smooth driving,"

JACKIE STEWART SHOWS WHY GREAT DRIVERS ARE SMOOTH DRIVERS

There are many ways of insulting people, says former championship race car driver Jackie Stewart, and one of the surest is to tell them they are bad drivers. ``They won't believe you,'' he said. ``It's tough for people to admit they don't do it right.''

www.deseret.com

No one ever won a race meandering though eh???

 

[Pontoneer]

I call them 'stickies'.

As they stick with you doing that over long stretches.

I like to keep my windscreen clean ; sometimes I see them in my mirrors copying me when I do it .

 

[Pontoneer]

It would be so much easier to tick in and follow at the same constant speed.

Maybe they’re hyper milers drafting, and taking it in turns to lead and follow.



PS I always think that terms should be draughting rather than drafting.

One drafts a memo , or a document , but to do with air flow or any form of fluid mechanics , I'm sure draughting is the correct term .

 

[Bobby Dazzler]

One drafts a memo , or a document , but to do with air flow or any form of fluid mechanics , I'm sure draughting is the correct term .

Me too but it does seem to be referred to as “drafting”, perhaps an Americanism due to it’s use in NASCAR.

 

[Pontoneer]

More cars on the roads compared to the "good ole days?"

Like this dip into driving on the A4 forty years ago, perhaps? It does look a little bit quiet.

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I know that film , always liked his use of the horn ..... and again !

 

[HappytalkAgain]

I know that film , always liked his use of the horn ..... and again !

You’re back mate. When did you sneak in??

 

[Pontoneer]

Who would want to take photos on this 1960's camera?

You can't even use it to put selfies to your Insta !

View attachment 145541

I still have my Instamatic 500 , which I used mainly to shoot square format slides on . I 'could' still use it as I bought a refillable 126 cassette , into which I could load 35mm film , but these days it is gathering dust in my living room , along with a few other cameras I used down the years . I still occasionally shoot medium format , but apart from that , haven't shot any film in years .

 

[Pontoneer]

You’re back mate. When did you sneak in??

I've been around for a while , just look in every now and again , thanks .

 

[Pontoneer]

I have to disagree with that!
Acceleration changes electrical energy into potential energy. Braking changes that energy into heat, to warm the planet and disappear from the vehicle.
I believe braking is the no 1 range killer on a EV's, it's just a waste of energy, and worse still, I slows you down!
Observation and anticipation is the key to hone on the range... spelling mistake intentional...this time!

That applies to any kind of driving , no matter the fuel source .

 

[Pontoneer]

That's not how EVs work... braking doesn't generate heat because there's no (or very little) friction, other than between the road and the tyres. EVs have regenerative braking. That's why driving an EV in city traffic is very economic, the more braking the more energy goes back into the battery. I get back into the battery about 25% of the electriity used, when driving around central London. And, when driving downhill, the car actually charges the battery as it is slowing down the car, increasing the remaining mileage. Acceleration is the big killer here. That, and high speed (70mph) motorway driving due to little braking and also due to air resistance.

Don't they have friction brakes as well as regenerative ( eddy current ? ) brakes like on trains ?

 

[Pontoneer]

Gawd I feel old. I can remember doing 70 on Park Lane and Embankment.

Someone else would have been driving, of course. A SAAB 900 Turbo, methinks.

Different times.

Ah - SAAB 99 Turbo would be another ULEZ exempt car ; think maybe the 900 just a little too new ?

 

[Pontoneer]

Yes, if we assume we are going to travel, then we must move, therefore acceleration is mandatory. The rate we accelerate is discretionary. Because we travel on roads, slowing down and stopping is something that happens. In an EV driven with some forward observation, the kinetic energy in the moving car can be returned to the battery with a reasonably efficiency. Using the brakes just completely wastes that energy as heat.
So I maintain that it is braking that is biggest danger to the range, as it is a complete energy loss.

If I remember my high school physics correctly , and I am peering through 50 odd years of cobwebs here , the amount of energy required to accelerate a given mass from one speed to another speed does not change with the rate of acceleration ; therefore , say , applying a force of 1N for 10 seconds should be exactly the same as applying a force of 10N for 1 second to achieve the same velocity . To then maintain that velocity only requires enough force to overcome losses , be it mechanical friction or air resistance .

I know that in practice , gentle acceleration tends to produce the best fuel economy , and avoiding unnecessary deceleration and re-acceleration through observation and planning is the best way .

 

[Pontoneer]

EVs turn stored electric energy into kinetic energy, then turns the kinetic energy back to stored electric energy when braking.

The energy loss is from kinetic and electric energy turning into heat. The heat is dissipatedvat from the tyres as result of friction with the road, from the car's exterior as result of wind resistance, from the electrical motors, and from the battery cooling system. This accounts for the energy losses when driving on level ground.

When driving uphill, some if the stored electric energy is converted to potential energy. When driving downhill, the potential energy is turned back into stored electric energy, again with losses resulting from heat dissipation.

Overall, an EV as a car is much more energy-efficient than a comparable ICE car, because there are far less losses resulting from heat dissipation.

However, the issue with the energy efficiency of EVs is in fact not with the car itself, but with the overall process of converting fuel to energy. The EV will see many losses even before the electricity reaches the battery. The higher efficiency of the car itself does not compensate fully for the losses between the power plant and the home or public charger.

In any event, EVs do not use the brake discs for braking, instead they brake using the resistance of the electromagnetic field inside the motor, which is a frictionless process (hence the greater efficiency).

Except where the electricity is generated from 'free' sources such as hydro-electric , wind , photo-voltaic or wave energy ; if one ignores the materials and energy required to create the infrastructure in the first place ...