How does a electric car compare with a diesel performance

How does a electric car compare with a diesel performance

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Discussion

kambites

57,441 posts

167 months

Tuesday 11th December 2018
quotequote all
poing said:
It's why a lot of smaller ones are restricted in top speed, often to less than 100mph.
As the push for greater range continues, I think we'll see less of that because increasing battery capacity essentially gives you more power for free (or at least for negligible cost). Not that there's anything wrong with a UK market road car being limited to, say, 90mph.

Max_Torque

14,066 posts

163 months

Tuesday 11th December 2018
quotequote all
kambites said:
poing said:
It's why a lot of smaller ones are restricted in top speed, often to less than 100mph.
As the push for greater range continues, I think we'll see less of that because increasing battery capacity essentially gives you more power for free (or at least for negligible cost). Not that there's anything wrong with a UK market road car being limited to, say, 90mph.
It's more about the trade off between maximum torque (and hence gradeability) and the road speed at which peak power is gained for a vehicle with a single speed transmission. A typical electric machine with a CPSR of say 2.5:1 means that if you set peak power to 40mph, you run out of available motor speed at 100mph.

kambites

57,441 posts

167 months

Tuesday 11th December 2018
quotequote all
Indeed but the higher your peak battery draw (assuming battery is power limited, as usually seems to be the case), the higher up the speed range you can push peak power without compromising low-speed performance unacceptably.

For example I would guess that the two different power levels of the Kona EV will have slightly different gear ratios to allow the higher top speed of the more powerful model?

Edited by kambites on Tuesday 11th December 11:11

colin_p

2,069 posts

158 months

Tuesday 11th December 2018
quotequote all
I see a business opportunity.

Using diesel engined vans with diesel engined generators in the back to go out to and emergency charge dead flat and stranded electric cars.

And once that kicks off enough to fund some development, design a ICE generator pack that could go onto an EV roof rack.

You get to work, park up, pull the rip chord on the Briggs and Stratton that is strapped to the roof to start it up and then let it run all day in the works car park. I'm sure you could even have the roof-rack engine running whilst you are driving.

Afterall, them new power stations are not going to build temselves.

Max_Torque

14,066 posts

163 months

Tuesday 11th December 2018
quotequote all
kambites said:
(assuming battery is power limited, as usually seems to be the case),
The battery these days is not the limit, because they have got so big in order to give enough range, that the power requirements are easily handled, especially for transient events like WoT accels. IN any case, because the driving inverter acts as a voltage /current convertor, so you can pull peak power from the battery at any vehicle speed, whereas the eMachine can only make peak power once it has reach the minimum road speed that co-incides with the motors fundamental peak power speed.

(The big compromise is getting sufficient zero speed tractive efffort (stall torque) to pass the various sign off tests (like driving over a kerb, or out of a pot hole, or up a "US" drive etc) with a fully laded vehicle and still get a suitable top speed. The i3 for example is a 4 seater (rather than 5) simple to limit it's maximum mass and hence be able to pass those tests .)


Edited by Max_Torque on Tuesday 11th December 11:17

kambites

57,441 posts

167 months

Tuesday 11th December 2018
quotequote all
colin_p said:
I see a business opportunity.

Using diesel engined vans with diesel engined generators in the back to go out to and emergency charge dead flat and stranded electric cars.
You don't need the generator, just a diesel van and a tow rope. smile

essayer

6,270 posts

140 months

Tuesday 11th December 2018
quotequote all
kambites said:
You don't need the generator, just a diesel van and a tow rope. smile
You joke, but this guy (driven from the Netherlands to, so far, Australia in his converted EV) got stuck a few times, and got towed, regenerating while he did so:
https://twitter.com/WiebeWkkr/status/1054602522134...

Not as efficient energy-wise, but more efficient time-wise wink

Herbs

4,781 posts

175 months

Tuesday 11th December 2018
quotequote all
Surely that's what an i3 ReX is.

Plug Life

978 posts

37 months

Tuesday 11th December 2018
quotequote all
Herbs said:
Surely that's what an i3 ReX is.
Was, they stop selling it in Europe with the latest 120Ah model.

Register1

659 posts

40 months

Tuesday 11th December 2018
quotequote all
MrOrange said:
F4R said:
I was following a leaf once and both of us were stuck behind a slow moving HGV up a steep hill. To my amazement, the leaf successfully overtook it without any trouble. If you like diesel torque you'll love electric
A Nissan Leaf has 240lbft of torque. That’s more than my 3 litre, flat-6, Subaru Legacy Outback.
Still less than half of my wife's Touarag.

otolith

38,762 posts

150 months

Tuesday 11th December 2018
quotequote all
Comparing peak torque figures for powertrains with very different torque curves and gearing is pretty meaningless.

996TT02

2,973 posts

86 months

Tuesday 11th December 2018
quotequote all
otolith said:
Comparing peak torque figures for powertrains with very different torque curves and gearing is pretty meaningless.
Indeed. Which is why my vintage 'cruiser with a 2.8L n/a diesel engine is fantastic and completely unstoppable seriously offroad, fully laden 600kg+ taking gross weight to 2.6T whereas OH's Qashqai 1.5 turbo diesel was very nearly stuck up a moderately rough gradient with only the driver at the wheel. Nothing happens unless the motor is revved, and then you get crazy wheelspin.

Toyota 188nm torque, Nissan 260nm.

Now electric must be something else altogether, with the torque being where it is.



underphil

1,089 posts

156 months

Tuesday 11th December 2018
quotequote all
Register1 said:
MrOrange said:
F4R said:
I was following a leaf once and both of us were stuck behind a slow moving HGV up a steep hill. To my amazement, the leaf successfully overtook it without any trouble. If you like diesel torque you'll love electric
A Nissan Leaf has 240lbft of torque. That’s more than my 3 litre, flat-6, Subaru Legacy Outback.
Still less than half of my wife's Touarag.
The last V8 Formula One engines also had half the torque of your wife's Touareg. Maybe Renault were missing a trick not using the Touareg engine

cptsideways

13,011 posts

198 months

Tuesday 11th December 2018
quotequote all
colin_p said:
I see a business opportunity.

Using diesel engined vans with diesel engined generators in the back to go out to and emergency charge dead flat and stranded electric cars.

And once that kicks off enough to fund some development, design a ICE generator pack that could go onto an EV roof rack.

You get to work, park up, pull the rip chord on the Briggs and Stratton that is strapped to the roof to start it up and then let it run all day in the works car park. I'm sure you could even have the roof-rack engine running whilst you are driving.

Afterall, them new power stations are not going to build temselves.
Try a 17ton truck with a lorry engine in the back & a huge diesel genset & a rapid charger. About 200l of diesel a day it used.

CubanPete

2,117 posts

134 months

Tuesday 11th December 2018
quotequote all
gazza285 said:
Do you have a drive? Can you guarantee a parking spot near enough? What if you live in a block of flats?
You're clutching at straws now gazza.

Some ICE cars are too big / too small / too slow / too expensive to insure. We can all find an example where something isn't appropriate for something else. Not sure what point you are trying to make but you have made it, so please take a rest.

colin_p

2,069 posts

158 months

Tuesday 11th December 2018
quotequote all
cptsideways said:
colin_p said:
I see a business opportunity.

Using diesel engined vans with diesel engined generators in the back to go out to and emergency charge dead flat and stranded electric cars.

And once that kicks off enough to fund some development, design a ICE generator pack that could go onto an EV roof rack.

You get to work, park up, pull the rip chord on the Briggs and Stratton that is strapped to the roof to start it up and then let it run all day in the works car park. I'm sure you could even have the roof-rack engine running whilst you are driving.

Afterall, them new power stations are not going to build temselves.
Try a 17ton truck with a lorry engine in the back & a huge diesel genset & a rapid charger. About 200l of diesel a day it used.
I'm talking about charging an electric car, are you talking about running a fairground, with all the pretty lights?

CubanPete

2,117 posts

134 months

Wednesday 12th December 2018
quotequote all
I'd love an electric car, or even two.

We would still need a 'distance car' as parents and inlaws live several hours drive away (and a weekend car!).

We have a massive drive gazza, so that isn't a problem, the irony is our commutes are too short to make the upfront capital cost or monthly payments worth it as the fuel savings wouldn't pay back. As they become available on the used market for smaller sums it is something we will almost certainly do.

Evanivitch

4,731 posts

68 months

Wednesday 12th December 2018
quotequote all
colin_p said:
I see a business opportunity.

Using diesel engined vans with diesel engined generators in the back to go out to and emergency charge dead flat and stranded electric cars.

And once that kicks off enough to fund some development, design a ICE generator pack that could go onto an EV roof rack.

You get to work, park up, pull the rip chord on the Briggs and Stratton that is strapped to the roof to start it up and then let it run all day in the works car park. I'm sure you could even have the roof-rack engine running whilst you are driving.

Afterall, them new power stations are not going to build temselves.
The RAC tried that, and then abandoned it very quickly. Much easier to tow/flatbed to the nearest charging point.

essayer

6,270 posts

140 months

Wednesday 12th December 2018
quotequote all
CubanPete said:
We have a massive drive gazza, so that isn't a problem, the irony is our commutes are too short to make the upfront capital cost or monthly payments worth it as the fuel savings wouldn't pay back. As they become available on the used market for smaller sums it is something we will almost certainly do.
Not sure if you commute to a station, but some stations (the Indigo ones, usually) offer free parking to EVs, for now at least!

MrOrange

1,698 posts

199 months

Wednesday 12th December 2018
quotequote all
CubanPete said:
I'd love an electric car, or even two.

We would still need a 'distance car' as parents and inlaws live several hours drive away (and a weekend car!).

We have a massive drive gazza, so that isn't a problem, the irony is our commutes are too short to make the upfront capital cost or monthly payments worth it as the fuel savings wouldn't pay back. As they become available on the used market for smaller sums it is something we will almost certainly do.
Don’t just focus on the fuel cost. It’s the total running costs: free/subsidised parking, zero RFL, no congestion charge/emission penalty, simpler vehicle (= opportunity for lower servicing costs and longer vehicle life)

Distance car? Rent one, its mostly a better option anyway as you can rent an eco-mile muncher designed just for that journey’s needs. My daughter has no car (lives in town) and when she needs to travel distance she rents an 70mpg eco-box for about a tenner a day.

Weekend car can then be a pure hobby thing. V8, open topped, CO2 spewing monster


Edited by MrOrange on Wednesday 12th December 11:57