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Travesty! Write to your MP!

3K views 10 replies 8 participants last post by  TheDeuce 
#1 ·
#3 ·
amiller001 said:
Now if they made the outside lane 70mph for only green number plate electric vehicles there would be a sudden HUGE increase in EV purchases. If only...
I'd vote for you.
 
#5 ·
But EV's too are less efficient at 70mph than 60mph, quite considerably so. On a long drive 50-55mph is about the peak in terms of efficiency for both EV and ICE.

All about air resistance... Regardless of the power source. Albeit EV is obviously greener than ICE at any given speed.

Not suggesting that I agree with a reduction in speed limits though! The way I see it, progress has to be overall progress. Making cars a bit greener whilst also slowing them down is more like a trade-off. A bit like the early energy saving light bulbs were touted as progress - ignoring the fact that whilst saving the planet we all had to stand around in the gloom whilst they 'warmed up' and they cost way too much!

I would vote for leaving the speed limit where it is and bringing in usage based road tax. That way anyone who actually needs to make a trip can do so at the already established speeds. Those that don't really need to travel (covid has proven many really don't..) or those that frankly don't need to be in as much of a hurry, are persuaded to rethink. They could do that without monitoring speed or location of cars, just reporting on the burn rate of the energy source would be enough to set a limit that the driver could choose to break or not. And... if an EV manufacturer could enhance efficiency such that their car could travel at 70 whilst only using energy at the rate considered to be what is required to travel at 60, then that would also be healthy progress. So much more intelligent than a blanket speed reduction and it's not as if the connected technologies to drive such progress aren't already available.
 
#6 ·
Hi TheDeuce,

Sorry to break a bubble, but the most energy efficient travel speed for EVs is around 20mph. Look at the Koreans who pushed a Kona past 1000km range on a single charge...They did so at 30km/h, be sure that this speed was not randomly chosen...
Are you prepared to endorse, even intellectually, your reasoning?

Anyway, the measure is supposed to reduce toxic emissions (sooth, NOx etc) near the motorways. Clear that electric cars do not contribute to those...

The proposed measure is of course merely the result of some politicians who want to be seen doing something, anything... And this is what they came up with 🤕

In terms of CO emissions it makes about as much difference as switching air-conditioning on or off... I wonder when one will propose to outlaw airco?
 
#7 ·
Grunt said:
Hi TheDeuce,

Sorry to break a bubble, but the most energy efficient travel speed for EVs is around 20mph. Look at the Koreans who pushed a Kona past 1000km range on a single charge...They did so at 30km/h, be sure that this speed was not randomly chosen...
Are you prepared to endorse, even intellectually, your reasoning?

Anyway, the measure is supposed to reduce toxic emissions (sooth, NOx etc) near the motorways. Clear that electric cars do not contribute to those...

The proposed measure is of course merely the result of some politicians who want to be seen doing something, anything... And this is what they came up with 🤕

In terms of CO emissions it makes about as much difference as switching air-conditioning on or off... I wonder when one will propose to outlaw airco?
No bubble broken - I was going on the basis of highway cruising speeds as that's what the thread was based upon.

Sure, rolling at low speed and no air resistance, no energy lost to heat as very little current transferred to the motors, that should indeed be the optimum for range. Kind of hard to argue it's a realistic usage scenario though!

Can't really outlaw aircon, people drive for work and have a right to min/max temperature... All they can consider doing (other than legislate to encourage more EV tech and uptake) is to reduce the speed to enhance the economy - for all cars, EV's included. Doubt it'll fly though - this is the kind of idea that gets discussed for years and then at general election time it's the kind of idea that gets dismissed in return for appearing liberal and getting a few hundred thousand voters back on side. I think it's fairly obvious that most British motorists are happy enough at 70, don't wish to go any slower and feel pretty safe. Car economy has improved massively in the last 20 years without changing the speed limit.. Honestly, how much appetite is there really going to be to change a law everyone is settled with for the sake of a relatively small return in lowering energy usage?? I can't see it.

Lastly, in favour of EV's - one of the biggest draws for early adopters has been speed! You get to save energy 95% of the time and the other 5% you get to enjoy the wave of torque... That should be all the proof required that people are converted most easily to greener ways when they can do so without making a sacrifice in terms of fun/lifestyle. Converting more people to EV's would do far more than making ICE cars slightly less wasteful for the relatively short time they remain the majority of car on the road. As I said - I'm a fan of progress. Genuine progress, not compromise - it's not progress unless you can put one foot forward without the other taking a step back. Greener cars is progress, slower travel is a step back.
 
#8 ·
On the M6 roadworks there is an experimental 60mph limit with average speed cameras, it is a very orderly drive and I'm sure suits 90% of drivers. The downside of course is that it takes the fun out of driving and stops the aggressive drivers doing 90 plus, not just BMW/Audi drivers, white vans and any boy racer, it's hard to justify deliberate law breaking.
There are plenty of environmentalists who want cars restricted and will use any excuse to get their way.
 
#9 ·
Grunt said:
The proposed measure is of course merely the result of some politicians who want to be seen doing something, anything... And this is what they came up with

In terms of CO emissions it makes about as much difference as switching air-conditioning on or off... I wonder when one will propose to outlaw airco?
See below ID3 efficiency test results done by Bjorn Nyland. VW ID3 consumption goes up 50% when driving 75mph instead of 56mph.
So higher speed is a much greater factor than AC on/off certainly in the relative mild UK climate.

Results at 90 km/h (56 mph):
Energy consumption of 135 Wh/km (217 Wh/mile)
Range of 413 km (257 miles)

Results at 120 km/h (75 mph):
Energy consumption of 205 Wh/km (330 Wh/mile)
Range of 271 km (168 miles)
 
#10 ·
Jelle,

I know, I was joking :) But it wasn't really funny, so I can't be upset that you did not see it as joking!
Anyway, I will not be surprised the day a politician thinks that it may be a good idea to forbid airco...

(BTW, 52% is a big difference in consumption between 90 and 120 in that ID3. Aero drag will consumption per kilometer will increase with 33%, rolling resistance will increase less, perhaps 15%; so the rest of the increase comes from decreased drivetrain efficiency - more heat loss because the energy draw from the battery is higher. Or from different circumstances not accounted for, traffic/temperature/...)
 
#11 ·
Grunt said:
Jelle,

I know, I was joking :) But it wasn't really funny, so I can't be upset that you did not see it as joking!
Anyway, I will not be surprised the day a politician thinks that it may be a good idea to forbid airco...

(BTW, 52% is a big difference in consumption between 90 and 120 in that ID3. Aero drag will consumption per kilometer will increase with 33%, rolling resistance will increase less, perhaps 15%; so the rest of the increase comes from decreased drivetrain efficiency - more heat loss because the energy draw from the battery is higher. Or from different circumstances not accounted for, traffic/temperature/...)
The same politicians that implement laws to ensure the workforces have the human right to work within a certain temperature band? Some firms have subsequently been required to install permanent/temporary AC in offices. Why should a travelling employee in their EV company car be denied the same? The simplest thing to propose is always going to be a reduction in speed as the most wasteful part of road travel for any car is fighting air resistance at speed. As I've already said, for other reasons I can't see that proposal actually being successful - but if the greens are to push for any new measures, that is by far the most obvious and effective one. If all cars drove at 50 mph tops it'd make way more difference than the introduction of hybrid/EV has done so far!
 
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