Gotta gas up..

That's a lot of mental gymnastics. 2 gallon equivalent would be a quantity in kWh.
Not really metal gymnastics IMO. It's pretty easy to see that an EV "MPH" charging event results in X kWhs of energy put in the battery that is good for Y miles, just like putting X gallons of gas in an ICE is good for Y miles - example was in post #126.

The metric of EV charging in "mph" is like going to gas pump and filling up at "mph", it would just be a lot faster with gasoline. It's a perversion of proper units in an apparent effort to dumb things down because people aren't used to using kWh on a regular basis. Ultimately, you'll get billed for the kWh provided, so I really fail to see the value of this "unit of obfuscation".
Sure it's making it easier (a dumbing down) for EV owner's to grasp the concept of charging, and how much range you'd get by charging at a certain rate for a certain time. Charging at a rate of "100 MPH" would put enough juice in the battery in 1 hour to be able to travel about 100 miles. Just like putting 4 gallons of gasoline in an ICE that got 25 MPG would give about 100 miles of travel. Hey, it works for what it's meant to do (give quick info) ... so what's so bad about that?
 
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Hey, it works for what it's meant to do (give quick info) ... so what's so bad about that?
Because it's using a unit defined for motion/speed and applying it to capacity, for which a measure (kWh) already exists. On top of that, it's simply inaccurate as range changes based on myriad factors already discussed. The proper unit, kWh, does not vary in accuracy, just like gallons or litres.

I stand by the fact that it is ridiculously clumsy and over-complicates something by trying to make it simpler; dumbing it down.

It's the equivalent of gas pumps giving you a rough measure of potential range based on what you are driving, rather than gallons or litres being put in the tank. But you are still billed based on a rate for gallons or litres and can just look at your estimated range on your display if you wanted that rough idea after the fact.

If you saw the example charger I showed, it quite clearly showed kW as the rate of charge and kWh as the volume. Perfectly logical and exactly what I'd expect. The kWh component and cost are the same as your gallons and cost on a traditional fuel pump. Nobody is going to have a hard time quickly wrapping their heard around that. This seems like an answer to a question nobody asked and that's why I'm taking such a strong issue with it. Let people learn kWh, it's going to help them out in a future that's looking to be more and more electrified.

And somewhat of a tangent here, but this, electrical illiteracy, is a huge impediment in having a well-based discussion about electricity systems. People don't understand what means what and even journalists are notorious for misrepresenting output (kW/MW/GW) as output capacity (kWh/MWh/GWh/TWh). I had a great dialogue with a woman who lived near an Ontario wind farm and just assumed that if they were spinning, they were making their rated capacity. It was difficult to bring her down to earth and explain that nameplate capacity does not equal actual output and that just because a wind turbine is rated for 3MW doesn't mean it's equivalent to a hydro-electric dam of the same capacity, nor does 900MW of wind compare to 900MW of nuclear or gas. This brought us around to output capacity, capacity factor...etc. This is all stuff she thanked me for explaining. Just think how much better informed consumers would be on these topics if they already had a fundamental understanding of the units because they interact with them every day like gallons or litres?

As I said earlier, the answer is never less knowledge.
 
Maybe the ICE car makers should remove the MPG and Range readouts and just show what percentage the gas tank is filled (like percent battery charge on an EV). Then the driver can just do the math to figure out how far he can go, lol.
Back when I had a proper analog fuel gauge and knew from experience how much was left at various points on the gauge, and could interpolate, I could do the math to figure how far I could go. Now I have what amounts to an ultra-low-resolution bar graph gauge, and can only make a rough guess.

As far as charging electrics, miles per hour of charge time is a useful approximate practical concept, even if you know exactly what kw·hr means (3,600,000 joules).
 
Because it's using a unit defined for motion/speed and applying it to capacity, for which a measure (kWh) already exists. On top of that, it's simply inaccurate as range changes based on myriad factors already discussed. The proper unit, kWh, does not vary in accuracy, just like gallons or litres.
Don't know why people are so hung up on that metric considering the context it's used for. Don't you agree that it takes a certain amount of energy capacity to go a certain distance, be it potential enegry stored in the form of electricity in the battery or liquid fuel in the tank? If the battery charges at "100 MPH" for 1 hour then it's essentially charging at X kWh and will give enough energy for that EV to travel ~100 miles if the software is accurate in expressing that metric.

The range changes based on the actual driving conditions regardless of what units of energy are used, or if the vehicle is EV or ICE.

I stand by the fact that it is ridiculously clumsy and over-complicates something by trying to make it simpler; dumbing it down.
For what it's meant for, it really doesn't make anything that clumsy or over-complicated ... it's actually trying to make it less complicated by dumbing it down, and it's useful for what it's meant to express. There are plenty of other metrics also available on every EV to know what's going on with the battery charging rate, capacity and resulting range.

It's the equivalent of gas pumps giving you a rough measure of potential range based on what you are driving, rather than gallons or litres being put in the tank. But you are still billed based on a rate for gallons or litres and can just look at your estimated range on your display if you wanted that rough idea after the fact.
What if a gas pump connected wireless to your ICE when you pulled up to the pump, and the pump computer sees that the average MPG of your ICE is getting 25 MPG over many tank fulls of stored data. The pump readout then shows how many potential miles of range you are pumping into your tank based on the vehicle's MPG history instead of the number of gallons on the readout, and the faster the gas was pumped into the tank, the higher the readout showing the "refueling rate". That's basically what EV "MPH" is showing while the battery is charging. What's so bad about that? I'm betting if gas pumps did that people would easily understand the concept.

If you saw the example charger I showed, it quite clearly showed kW as the rate of charge and kWh as the volume. Perfectly logical and exactly what I'd expect. The kWh component and cost are the same as your gallons and cost on a traditional fuel pump. Nobody is going to have a hard time quickly wrapping their heard around that. This seems like an answer to a question nobody asked and that's why I'm taking such a strong issue with it. Let people learn kWh, it's going to help them out in a future that's looking to be more and more electrified.
I'm sure anyone who owns and uses an EV will figure out all the available metrics to fully understand the vehicle. EV MPH charging rate is one of them, at least for those Tesla guys.

As I said earlier, the answer is never less knowledge.
EV "MPH" charging rate isn't the only metric available ... many ways to skin the EV battery charging cat and the resulting estimated driving range.
 
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I don’t think I know anyone except myself who talks about mpg let alone kWh. They get gas and look at the price to pay. With ev they look at the graphic of the battery charge level, or wait until the charger turns off, then pay or leave if it’s free. They don’t care about the rest of it. Their calibration is a car seems to take more gas or a car takes less gas and that’s the extent of it.
 
My 2 cents....
I certainly don't see any problem with different display readouts on a car like a Tesla. It's just a programming task that could be end user configurable. Easy peasey; I have been doing this kinda thing forever as a business app developer. A useful app gives information based on end user need. The programmer provides the tool, the end user picks up and uses the tool based on their need.

I believe most people don't care about amps, kWh, gallons, whatever, beyond unit cost. Costco gas is a winner because it is usually low cost per gallon, resulting in lower operation cost. However, these cars are different; most EV charging is done at home. Owners probably need to understand time-of-use prices more than quantity.
 
Tried to sift through all of this. I saw something similar when Canada went metric in 1976. The gas pumps went to litres ( Canadian spelling) and the road signs went to kilometres.( Canadian spelling). The old boys were hopeless with it.

Even today, over 40 years later some people will still talk about mpg instead of litres per 100 km. My Burb burns 16 litres per 100 km. My Taurus burns 10 litres per 100 km. I once rented a Volkswagen Golf and burned 7 litres per 100 km. Wow.

How many mpg? Couldn’t care less. :)

We’re in new territory with all this. Lot’s of people will never get it.
 
Tried to sift through all of this. I saw something similar when Canada went metric in 1976. The gas pumps went to litres ( Canadian spelling) and the road signs went to kilometres.( Canadian spelling). The old boys were hopeless with it.

Even today, over 40 years later some people will still talk about mpg instead of litres per 100 km. My Burb burns 16 litres per 100 km. My Taurus burns 10 litres per 100 km. I once rented a Volkswagen Golf and burned 7 litres per 100 km. Wow.

How many mpg? Couldn’t care less. :)

We’re in new territory with all this. Lot’s of people will never get it.

But they've all adapted from Mph to km/h, which is very much the corollary in going from gallons or litres to kWh. My position is that people should learn the proper units, units which, in this case, they should already be at least somewhat familiar. Perverting an existing unit to avoid that process isn't doing anybody any favours, regardless of the valiant efforts put forth by Zee to justify it.

On that note, I'm bowing out of this thread.

Merry Christmas everyone.
 
On that note, I'm bowing out of this thread.

Merry Christmas everyone.
Overkill, you added a ton (maybe a kWh?).
You have inspired me to learn just what a kWh is.

It is easy for me to read stuff I agree with or perhaps even know.
It is the new stuff that allows me to learn.

Just don't overamp me with inspiration!
 
None of this would be a problem if you have a Pee Chee. With the Pee Chee you can solve any mathematical equation.
 
Overkill, you added a ton (maybe a kWh?).
You have inspired me to learn just what a kWh is.

It is easy for me to read stuff I agree with or perhaps even know.
It is the new stuff that allows me to learn.

Just don't overamp me with inspiration!
Agreed, Overkills posts and knowledge on the power stuff is hugely contributory to the discussion.
 
But they've all adapted from Mph to km/h, which is very much the corollary in going from gallons or litres to kWh. My position is that people should learn the proper units, units which, in this case, they should already be at least somewhat familiar. Perverting an existing unit to avoid that process isn't doing anybody any favours, regardless of the valiant efforts put forth by Zee to justify it.

On that note, I'm bowing out of this thread.

Merry Christmas everyone.
If you ever get a Tesla, better turn off the "MPH" charging info, or put a piece of black tape over it ... :LOL:

j/k Overkill ... have a great Christmas bud.
 
Overkill, you added a ton (maybe a kWh?).
You have inspired me to learn just what a kWh is.
It's easy. One kWh is the amount of energy that would power a device using 1 kW for 1 hour. A kW of juice flowing for 1 hour.

If the device used 0.5 kW (500 W), then 1 kWh of energy would power it for 2 hours ... and so on.
 
It's easy. One kWh is the amount of energy that would power a device using 1 kW for 1 hour. A kW of juice flowing for 1 hour.

If the device used 0.5 kW (500 W), then 1 kWh of energy would power it for 2 hours ... and so on.
OK.. How much different is it if I putt around vs testing 0-60 and 100mph on the freeway?
That hour thing makes no sense to me. Sounds like it assumes a given load.
 
OK.. How much different is it if I putt around vs testing 0-60 and 100mph on the freeway?
That hour thing makes no sense to me. Sounds like it assumes a given load.
I think most folks understand that with an ICE or an EV - how you drive impacts range …
Even the guy who jacked a Hell Cat … outran the law and almost the news helicopter (was zoomed out) met his fate by running out of gas from the high speed chase 👀
 
OK.. How much different is it if I putt around vs testing 0-60 and 100mph on the freeway?
That hour thing makes no sense to me. Sounds like it assumes a given load.
If you do high load current draw from the battery, then 1 kWh is going to be used up faster. If the draw from the battery was for example 10 kW continuous, then it would only take 6 minutes to use 1 kWh of energy. That's 60 min divided by 10 (10 times 1 kW). But if the draw was only 1 kW then 1 kWh of stored energy would power it for 1 hour. If the draw was 2 kW, the then 1 kWh would last 30 minutes. It's just how much juice for X amount of time that you are using out of a finite amount of stored juice, and the use conditions (load draw from the battery) has an impact on the depletion time of the battery.
 
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I think most folks understand that with an ICE or an EV - how you drive impacts range …
Even the guy who jacked a Hell Cat … outran the law and almost the news helicopter (was zoomed out) met his fate by running out of gas from the high speed chase 👀
OK. So I guess the primary need is to see how much you buy when charging?
Because from a driving standpoint, remaining distance (miles, km) would be far more useful.

The remaing gallons, kWh or whatever is not what is important. What is important is the distance you can travel.
 
OK. So I guess the primary need is to see how much you buy when charging?
Because from a driving standpoint, remaining distance (miles, km) would be far more useful.
Yep … People get through life with relative comparison …
I made it to Houston and back on a half tank before …
Don’t see why they can’t do something similar with EV
My half charge got ‘er done … full charge back home …
Folks so often are running the same routes anyway …
 
This has got to be one of the silliest posts ever. What most cars have are % of full, same as a Tesla. But with a Tesla, because it can charge at different rates (due to % of full and more specifically, voltage input), it is important to know rate of charging as well. Here is a scenario. Say I am on a trip and I run my battery down and it's time to go home. I live 30 miles away. I go find a charger and plug in. Now I really only need approximately 30 miles worth of power. So in this case, since I just want to get home, it is nice to know, will it take 15 minutes to get the miles worth I need....or 2 hours. That is the purpose of this guage. It's basically gauging time to charge. Now we all know, this is not the most accurate measure. But.....it does give me an idea of when the wife can expect me home. It's nothing more that that.....an approximate measure. Stop with the engineer speak...and the "not accurate speak". It's not applicable. Until we can gas up an EV quickly, this is a needed measure....
 
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