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Discussion Starter #1
I came across this & it got me thinking.
Electric car energy efficiency - Wikipedia

Electric car absolute efficiency is rarely discussed. There is the general debate asking if Electric cars are really more efficient that ICE cars. However, EV vs EV efficiency is never really mentioned. According to the chart, an Ionic driver is in fact twice as green as a BYD6 or Tesla driver.
This seems odd. One would assume a fair % of potential EV buyers would be exceptionally environmentally conscious & these absolute comparisons would be vital. People can debate the EV vs ICE topic forever. EV vs EV is much more clear cut. While the EPA ratings may be wrong, they are likely to be equally wrong for all cars & therefore give a good comparison.

Who is leading the EV debate?. Do we need EVs to accelerate from 0-100khp in 2 seconds? Do we need cars with top speeds of 250km/h?. Where, when & how are we ever going to use these features? It this not just the marketing people yet again telling us what we want?. All this extra HP seriously contributes to excessive emissions from ICE vehicles. It does the same for EVs even if there are no tailpipe emissions.

If the UK speed limit is 70 Miles per hour (112km/h) why do Govt not force car makers to limit cars to this speed? It would save lives, help the environment & stop people breaking the law. However, it would pretty much destroy the marketing departments of car makers. The anti-smoking laws seemed radical when they were introduced but are normal now. Plain packaging is next in the smoking game. The results with smoking are impressive.

If such a rule were introduced cars would become ever more efficient. Car makers could eliminate all that extra weight that is added with the 500hp engine, massive brakes etc. Cars would become light again & everyone knows the path to efficiency is light weight.

Govts everywhere are pouring money into EV subsidies to improve the environment. Forcing car manufacturers to limit top speed to 70mph & forcing slower 0-100kph acceleration would have an instant impact & cost nothing.
Once we have autonomous cars they will have to obey speed limits so maybe someone should be thinking along these lines?.

Just a little Sunday rant !
 

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Counter-rant time.

Marketing people don't tell us what we want. They may guess what we want or research what we want, but then they tell us what they're offering and we decide whether we like it. If people want efficiency more than acceleration, that's what the market will deliver.

There's an argument to say a 70mph limit would be dangerous. For example, if you need to get out of the way of a truck on the motorway and breaking isn't an option...

Efficiency is different in different situations. Teslas are better on the highway than on urban roads. Lighter cars with worse aerodynamics would be the opposite.
 

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It has come up a few times, I know because I usually get into the discussion along with other members engaging.

The basic point is that it took about 50 years before the first fuel efficiency target was put in place (by Hitler, bizarrely enough, when setting targets for his KdF-Wagen; 7L/100km target). Before then it was just a case of asking 'how far can it go' which is exactly where we are with EVs today.

If you look at EV brochures there will be a mi/kWh or kWh/100km figure, so you can compare them. But as to whether people are looking down a list of cars comparing mpg like they can with ICE, that rather depends on someone producing such a list, like the one you have linked to. They are not the sort of thing you see in the back of car magazines yet!!

However, there are many complexities here you might not realise. The EPA figure is 'from the wall' and so other factors come to bear such as charging efficiency. Brochure pricing displays battery-energy consumption, so the two are not comparable.

Charging efficiency will vary with the charging means, so for example a rapid charge might lose up to 20% of the energy in the process of charging, while a slow charge for a car with a charger specifically designed for that charge rate would be nearer 10%.

In some cases, like the Zoe, the charger is substantially inefficient at low charge rates than higher ones, I have heard suggestions that it might be as low as 30% losses, because of the way the charging circuits are designed, for other cars it may be different.

Do you include those figures?

When I drove a Kia Soul and a Leaf one weekend, I could get better mi/kWh than from the Leaf, but according to the EPA table I should not have done. The efficiency maps of different motors vary considerably according to topology and design and, perhaps (I do not know for sure) a motor of one design will be more efficient than another for a particular route. [Brochure mileage 143Wh/km for Soul 30kWh, 150Wh/km for Leaf ... which is the reverse of EPA]

Once we have tables that compare EVs like we do for ICE, and once people have enough real choice to pick between them, then the question of which are more efficiency will become a more serious one. At the moment, passenger car EVs are generally very similar in their overall energy consumption, +/- 10%. The Ioniq seems more efficient, many people say this, and that's good that we can see more efficient cars. The Outlander is not very efficient by comparison to the Leaf (for example), but you could have guessed that!
 

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On the subject of speed versus efficiency, actually EVs turn that on its head. Because an electric motor can deliver a lot more power over a short time (until it gets too hot) then delivering rapid acceleration becomes a doddle and does not impact overall efficiency because the rest of the time the same lightweight motor can just poodle around.

So delivering scorching 0-60 times does not at all imply poor efficiency.

Sustained high speeds might be more complicated, but it is not of the same order as ICE. With an ICE, more power generally means more engine, which means a bigger car to put it in, which in turn means more air resistance, which means more engine, etc. that is cyclic. Until you end up with a 'muscle car' and wonder why it isn't efficient any more.

EVs bypass all that nonsense, so long as you are not after sustained high speed, in which case EVs might not be the right choice anyway.
 

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I find your opinions on state control, errosion of freedom and removing choice to be somewhat insulting to a free democratic society.

In many cases of the law, it does not exist to stop you doing something illegal but to dissuade you from doing so and punish you if you do. The choice nearly always is exists because in nearly every case to remove that choice would be to errode other civil liberties.

A very good modern example of this is encrypted communication. Something our government has no clue about, how to manage or how to resolve. They think banning it might work, but that also massively impacts legal users and does little to solve the issue.

Once we have autonomous cars they will have to obey speed limits so maybe someone should be thinking along these lines?
Why do you think this?

My cruise control isn't limited to 70mph, there's no safety reason why it shouldn't be. If I choose to exceed the legal limit that is my choice. The increased risk to others, in the appropriate circumstances, is near nil.
 

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Discussion Starter #6
I find your opinions on state control, errosion of freedom and removing choice to be somewhat insulting to a free democratic society.

In many cases of the law, it does not exist to stop you doing something illegal but to dissuade you from doing so and punish you if you do. The choice nearly always is exists because in nearly every case to remove that choice would be to errode other civil liberties.

A very good modern example of this is encrypted communication. Something our government has no clue about, how to manage or how to resolve. They think banning it might work, but that also massively impacts legal users and does little to solve the issue.


Why do you think this?

My cruise control isn't limited to 70mph, there's no safety reason why it shouldn't be. If I choose to exceed the legal limit that is my choice. The increased risk to others, in the appropriate circumstances, is near nil.
I think this because when we have full autonomous cars the car manufacturer will be responsible for breaking the law, not the driver. If your autonomous car knowingly drives at 90 is a 50 zone & kills someone, it is not your issue, it the issue of the car maker. One case of this & they will be legally dead. Cruse control is set by you, your choice.

Did the Smoking ban insult you?. This is an erosion of freedom.
Not having fully automatic weapons available at LIDL in the UK is an erosion of freedom.
Do you not see a fair trade off between pubic safety & having less freedom if choice? How far do you want to take this? Should we all have free access to chemical & biological weapons?
I am not aware of too many products sold today that flagrantly set out to break the law the way cars do. It is like putting an automatic weapon in the hands of an 18 year old & asking him/ her to just fire one shot at a time.
 

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Another thought about Hyundai vs Tesla comparison: the Tesla S 75 has 2.3 times as much range as the Ioniq, so it needs to lug a whole load more batteries around. Range and efficiency are always going to be something of a trade-off.

I'm a bit uncomfortable high-powered hybrids (including mine, although it's a baby compared to some of the other offerings), but the Tesla has huge range and is pretty efficient, so I don't have a problem with the acceleration.
 

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I think this because when we have full autonomous cars the car manufacturer will be responsible for breaking the law, not the driver. If your autonomous car knowingly drives at 90 is a 50 zone & kills someone, it is not your issue, it the issue of the car maker. One case of this & they will be legally dead. Cruse control is set by you, your choice.
Why do you think the manufacturer will.be responsible for the vehicle? I see no barriers to allow user to control simple parameters (i.e. target speed, route, waypoints etc) of a vehicle they own.

Did the Smoking ban insult you?. This is an erosion of freedom.
Not really. It doesn't stop people from smoking, it just stopped their smoke impacting other people.

Not having fully automatic weapons available at LIDL in the UK is an erosion of freedom.
Indeed, and UK gun law is based on a long history of knee-jerk reactions to isolated incidents. FYI, civilians can own and fire fully automatic weapons in the UK. The hurdles are tall but like many weapons in the UK they are not banned.

Do you not see a fair trade off between pubic safety & having less freedom if choice?
I've made it clear I already do. But speeding isn't one of these instances.

How far do you want to take this? Should we all have free access to chemical & biological weapons?
Why are we comparing a mode of transport to a weapon specifically designed for no other purpose than open warfare?

I am not aware of too many products sold today that flagrantly set out to break the law the way cars do. It is like putting an automatic weapon in the hands of an 18 year old & asking him/ her to just fire one shot at a time.
Name an object. Anything. Knife? Steel rod? Rolled up newspaper? A peanut?

Say "I'm going to hurt someone with this", pick it up and walk into the street.

You just broke the law.
 

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I am not aware of too many products sold today that flagrantly set out to break the law the way cars do.
Your points about smoking and guns make perfect sense, but you lost me with this.

On private land or on the autobahn, speed in unrestricted by the law. I have a 150mph-capable car, but I don't break the speed limit.

On the flip side, I have bought several knives which are designed to be lethal and I could quite easily use to kill someone. I've chosen not to.

There's a debate to be had, but regulating cars to prevent them breaking the speed limit is nonsense. How are you going to regulate them to not run someone over at 25mph? How are you going to regulate them to not allow someone to use a mobile phone, smoke dope, drink more than the legal limit, park on double-yellow lines, drive away from an accident, etc, etc, etc?
 

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Discussion Starter #10
It has come up a few times, I know because I usually get into the discussion along with other members engaging.

The basic point is that it took about 50 years before the first fuel efficiency target was put in place (by Hitler, bizarrely enough, when setting targets for his KdF-Wagen; 7L/100km target). Before then it was just a case of asking 'how far can it go' which is exactly where we are with EVs today.

If you look at EV brochures there will be a mi/kWh or kWh/100km figure, so you can compare them. But as to whether people are looking down a list of cars comparing mpg like they can with ICE, that rather depends on someone producing such a list, like the one you have linked to. They are not the sort of thing you see in the back of car magazines yet!!

However, there are many complexities here you might not realise. The EPA figure is 'from the wall' and so other factors come to bear such as charging efficiency. Brochure pricing displays battery-energy consumption, so the two are not comparable.

Charging efficiency will vary with the charging means, so for example a rapid charge might lose up to 20% of the energy in the process of charging, while a slow charge for a car with a charger specifically designed for that charge rate would be nearer 10%.

In some cases, like the Zoe, the charger is substantially inefficient at low charge rates than higher ones, I have heard suggestions that it might be as low as 30% losses, because of the way the charging circuits are designed, for other cars it may be different.

Do you include those figures?

When I drove a Kia Soul and a Leaf one weekend, I could get better mi/kWh than from the Leaf, but according to the EPA table I should not have done. The efficiency maps of different motors vary considerably according to topology and design and, perhaps (I do not know for sure) a motor of one design will be more efficient than another for a particular route. [Brochure mileage 143Wh/km for Soul 30kWh, 150Wh/km for Leaf ... which is the reverse of EPA]

Once we have tables that compare EVs like we do for ICE, and once people have enough real choice to pick between them, then the question of which are more efficiency will become a more serious one. At the moment, passenger car EVs are generally very similar in their overall energy consumption, +/- 10%. The Ioniq seems more efficient, many people say this, and that's good that we can see more efficient cars. The Outlander is not very efficient by comparison to the Leaf (for example), but you could have guessed that!
Yes, for sure, include charging efficiency if such data is available. EPA data is not correct but it gives decent comparative numbers. No efficiency number can ever be correct as efficiency depends how a person drives, on weather conditions, topology, traffic & a myriad of other factors. EPA compares like with like. When we compare these numbers on a combined cycle the Ionic is seriously more efficient than (say) a fiat 500. My surprise is that the audience buying EVs does not take this more seriously as you would presume being ''green'' is a key motivator for moving to an electric car?.
 

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Discussion Starter #11
Why do you think the manufacturer will.be responsible for the vehicle? I see no barriers to allow user to control simple parameters (i.e. target speed, route, waypoints etc) of a vehicle they own.


Not really. It doesn't stop people from smoking, it just stopped their smoke impacting other people.


Indeed, and UK gun law is based on a long history of knee-jerk reactions to isolated incidents. FYI, civilians can own and fire fully automatic weapons in the UK. The hurdles are tall but like many weapons in the UK they are not banned.


I've made it clear I already do. But speeding isn't one of these instances.


Why are we comparing a mode of transport to a weapon specifically designed for no other purpose than open warfare?


Name an object. Anything. Knife? Steel rod? Rolled up newspaper? A peanut?

Say "I'm going to hurt someone with this", pick it up and walk into the street.

You just broke the law.
You are actually saying that speeding does not effect other peoples lives. WOW ! Tell that to the relatives of all those killed & seriously injured by speeding drivers. I am not advocating stopping people from driving just driving in an illegal manner. In a civil liberties context I believe smoking & speeding can both be judged in terms of the safety of others.

As we do not have clear legislation about Autonomous cars yet I can only speculate about what the rules might be. I very much doubt the car will have functionality to allow it break speed limits. We live in a litigious society. I am sure the manufacturer would eventually be held liable.

I am comparing a car to a weapon simply because you brought up freedom of choice. Should the public be allowed to do absolutely anything they want to do? Should they have absolute choice. I believe, in some circumstances, especially when the safety of others is concerned, liberty should be somewhat curtailed.
 

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Logical fallacy arguments are rarely all that compelling, the above included.

What do you propose we tell all those relatives who’ve lost loved ones to accidents where excess speed wasn’t a factor?

The most important safety component in a car is the nut behind the steering wheel. We’ve discussed it before, but dumbing down responsibility for driving will only lead to more accidents through erosion of skill and reliance on technology, which unfortunately and just like people is fallible.
 

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Discussion Starter #13
Counter-rant time.

Marketing people don't tell us what we want. They may guess what we want or research what we want, but then they tell us what they're offering and we decide whether we like it. If people want efficiency more than acceleration, that's what the market will deliver.

There's an argument to say a 70mph limit would be dangerous. For example, if you need to get out of the way of a truck on the motorway and breaking isn't an option...

Efficiency is different in different situations. Teslas are better on the highway than on urban roads. Lighter cars with worse aerodynamics would be the opposite.
Possibly the marketing people are not to blame but someone sets an agenda. The majority of start-up EV companies seem to focus on super-cars. I do not think the Joe public is telling them they want a supercar?. Magazines & TV want super-cars & people seem to like to look at them but very few people will ever have enough money to buy one. The green agenda suffers because it it not very sexy & maybe marketing just follows this. As a rule, lighter cars are more efficient but the average car weight gets heavier all the time as we all want bigger cars. People of course need a massive off road car to drop the one child to school every day !
 

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Discussion Starter #14
Logical fallacy arguments are rarely all that compelling, the above included.

What do you propose we tell all those relatives who’ve lost loved ones to accidents where excess speed wasn’t a factor?

The most important safety component in a car is the nut behind the steering wheel. We’ve discussed it before, but dumbing down responsibility for driving will only lead to more accidents through erosion of skill and reliance on technology, which unfortunately and just like people is fallible.
How is it a fallacy?
Road traffic injuries
Are 1.25 Million people not killed every year by cars & is speeding not a major contributor?

Fully agree that the nut behind the wheel is the weakest link. Fully disagree with your conclusion. I would have confidence that autonomous cars in a connected world will crash less than humans. We will see in the future.
 

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Discussion Starter #15
Your points about smoking and guns make perfect sense, but you lost me with this.

On private land or on the autobahn, speed in unrestricted by the law. I have a 150mph-capable car, but I don't break the speed limit.

On the flip side, I have bought several knives which are designed to be lethal and I could quite easily use to kill someone. I've chosen not to.

There's a debate to be had, but regulating cars to prevent them breaking the speed limit is nonsense. How are you going to regulate them to not run someone over at 25mph? How are you going to regulate them to not allow someone to use a mobile phone, smoke dope, drink more than the legal limit, park on double-yellow lines, drive away from an accident, etc, etc, etc?
My point is that you CAN easily limit speed in cars. You simply change a setting in the EMU & the car will not be able to go over 70mph. I believe most sat navs now know the speed limit everywhere so they can easily control car speed in any speed zone. Again, it is not hard. Cars are computers on wheels these days so getting the sat nave to send a signal to the throttle is somewhat simple.
It is impossible to limit the use of knives, it is possible to limit the speed of cars.
All whole series cars must have airbags & seat belts. We do not get a choice. Why is speeding different?
 

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Are 1.25 Million people not killed every year by cars & is speeding not a major contributor?
More people die from eating fatty pork based products, where is the bacon ban?

What about dementia, how’s about we invest time and money in problems that need solving rather than ones that dont.

Speed limit hasn’t changed for decades and road deaths have declined dramatically as cars have on the whole gotten faster.

The link is clear then let’s get rid of speed limits less people will die.
 

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Possibly the marketing people are not to blame but someone sets an agenda. The majority of start-up EV companies seem to focus on super-cars. I do not think the Joe public is telling them they want a supercar?. Magazines & TV want super-cars & people seem to like to look at them but very few people will ever have enough money to buy one. The green agenda suffers because it it not very sexy & maybe marketing just follows this. As a rule, lighter cars are more efficient but the average car weight gets heavier all the time as we all want bigger cars. People of course need a massive off road car to drop the one child to school every day !
I guess the startup super car is down to economics. If you're going to build a car without a production line, it's probably better for it to be premium. If you're a startup, you probably want the maximum publicity that a serious, sensible car might not generate. You're not going to generate many sales without a production line, so you're not targeting the biggest demand.

On the subject of large cars being used for the school run, maybe that's something else we should legislate against? After all, everyone should have a small car for the school run...
 

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You are actually saying that speeding does not effect other peoples lives. WOW ! Tell that to the relatives of all those killed & seriously injured by speeding drivers. I am not advocating stopping people from driving just driving in an illegal manner. In a civil liberties context I believe smoking & speeding can both be judged in terms of the safety of others.

As we do not have clear legislation about Autonomous cars yet I can only speculate about what the rules might be. I very much doubt the car will have functionality to allow it break speed limits. We live in a litigious society. I am sure the manufacturer would eventually be held liable.

I am comparing a car to a weapon simply because you brought up freedom of choice. Should the public be allowed to do absolutely anything they want to do? Should they have absolute choice. I believe, in some circumstances, especially when the safety of others is concerned, liberty should be somewhat curtailed.
Speed does not kill. We moved past that theory in the 19th Century.

It's entirely possible, and happens every day, to travel in excess of 70 mph in a modern car, on a modern road in reasonable weather conditions.

What you seem to confuse is speeding with loss of control or failing to drive to the conditions. The law also does this in most cases.

Regarding liberty, we all draw our lines at different points. So far you've completely failed to define your line, so I ask, where do you draw the line on the following, in broad terms: civil surveillance, freedom of movement (which includes motoring) and the right to defend yourself from harm?

Unless you've ever been involved in a Safety Case or the commercial aspects of Limitations of Use (I have) I can understand why you might draw such an extreme line on manufacturers control. Let me be clear, there is greater liability on the manufacturer limiting the use of their product than there is if they allow the user to make their own decisions.

Your comparison of a car with a WMD is entirely misplaced. One is designed for a single purpose, the other is designed for a wide, wide variety of uses that could be accident or otherwise lead to harm.

A car is already a licensed, registered, insured and inspected item. It's performance is limited by market forces and its safety features are generally driven by market forces too with a soft-touch approach from government.

Your assumption that speed is responsible for deaths is a gross misunderstanding of cause and effect.
 

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Discussion Starter #19
More people die from eating fatty pork based products, where is the bacon ban?

What about dementia, how’s about we invest time and money in problems that need solving rather than ones that dont.

Speed limit hasn’t changed for decades and road deaths have declined dramatically as cars have on the whole gotten faster.

The link is clear then let’s get rid of speed limits less people will die.
Well, if there were a law against eating pork I hope there would be enforcement. We do have laws against speeding. We have available technology to ensure speeding laws are obeyed (such as limiting the speed of a car using the EMU).
30 years ago everyone (where I lived) thought drink driving was perfectly fine. Thankfully attitudes have changed to drink driving, clearly they have not changed toward speeding. I presume a lot of money is invested in Dementia.
 

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My point is that you CAN easily limit speed in cars. You simply change a setting in the EMU & the car will not be able to go over 70mph. I believe most sat navs now know the speed limit everywhere so they can easily control car speed in any speed zone. Again, it is not hard. Cars are computers on wheels these days so getting the sat nave to send a signal to the throttle is somewhat simple.
It is impossible to limit the use of knives, it is possible to limit the speed of cars.
All whole series cars must have airbags & seat belts. We do not get a choice. Why is speeding different?
Are you serious? You want the speed limit in a satnav to be the method to enforce compliance with the actual speed limit? So when the satnav thinks there's a 50mph zone on a motorway that was removed weeks ago, you should be limited to 50mph? Are you going to sue the satnav providers if their limi databases aren't accurate?
 
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