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Tesla Model 3 Is The Most Efficient Electric Car On Highways

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I think Panasonic makes the batteries for the Prius. At least they used to do. And I think they make laptop batteries. And I know they make consumer batteries. I didn't know they ran the Gigfactory. But I'm pretty sure they make a lot more batteries than just for Tesla.
 
I highly disagree.
The best example I know of that shows the nonsensical results that come of MPGe is this,
The Long Ranger, a petrol generator towed behind a Toyota RAV EV

upload_2018-8-22_20-31-45.png


Given:
1. The thermo efficiency of petrol to electricity in the towed generator is quite a bit less than the therm conversion of petrol to mechanical in a Petrol RAV.
2. Conservation of energy still rules

Result: A gallon of petrol will push a petrol RAV further than a gallon of petrol in the Long Ranger.
Guess which car has the much higher MPGe ?
 
I would imagine the traditional battery makers like Panasonic are taking it seriously.



I guess the 3AWD came out while I was away. Is it getting fewer miles per charge than the RWD? I thought the Dual-Motor Model S got slightly more range than the RWD version??? What's going on there?
You are right that the MS dual motor versions get slightly better range than similar battery sized RWD. That was accomplished through the "Torque Sleep" feature, whereby the car while cruising at freeway speeds can switch torque to the front motor, that has a slightly higher ratio reduction gear, and allow the rear motor to free wheel without using any power. This is possible because the motors are three-phase induction AC, with stator electro magnets.

M3 uses a permanent magnet rear motor and the same induction front motor as MS dual motor cars. The front motor can be turned off when not required, but the permanent magnet rear motor cannot (it is always either delivering power or doing regen), so torque-sleep is not possible.
 
I think Panasonic makes the batteries for the Prius. At least they used to do. And I think they make laptop batteries. And I know they make consumer batteries. I didn't know they ran the Gigfactory. But I'm pretty sure they make a lot more batteries than just for Tesla.
Panasonic currently mainly produce car batteries for Tesla. They do have a contract to make batteries in the future for Toyota. However, the point is that the improvement in EV battery technology is mainly due to the efforts of Tesla. You can think of it as Tesla is the Architect and Panasonic is the construction company.

List of electric-vehicle-battery manufacturers - Wikipedia
 
3LR is 3814lbs which makes a difference in efficiency vs. 4072lbs.
I covered it here (post #54) and agin weight is NOT the case since the Model 3 AWD has the same efficiency and weights 4072 which is MORE than my ELR weighs, not less.

Corrected:
Tesla Model 3 AWD (Dual Motor and P3D) 4072 lbs
Cadillac ELR 4070lbs

Link to post:
Tesla Model 3 Is The Most Efficient Electric Car On Highways
Post:
JulienW said:
True that I quoted the AWD weight, BUT efficiency is the same and my point still stands. It not more efficient than my ELR because it weighs less. It is more efficient because Tesla is MILES ahead in EV controls, motors, systems and batteries.
 
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MPGe sucks and needs to be forgotten. There is no G(allon) in EV and MPGe needs to go the way of the last ICEage. EV's need to be rated in miles per kWh (or Kilometers per kWh for the rest of the world, we are so backwards for not adopting metric). The Model 3 is SUPER efficient at 122 MPGe and is equivalent to over 4.2 miles per kWh. Of course Tesla famously does it the Apple way (their way) and uses Wh per mile but the calculation is the same and is 238 Wh per mile.

My ELR "sucks" (electrons) and is only rated at 3 miles per kWh/333 Wh per mile.

Well, I agree with half of this statement.

MPGe is certainly a silly way to try to fit EVs into a gas paradigm, but it's somewhat useful in persuading the unwashed masses that EVs are worth looking at.

If we're going to get rid of it, though, I certainly wouldn't go with miles per kWh - I'd use the inverse, Wh per mile or kWh per hundred miles.

We aren't filling tanks from empty, or to full, and most trips are much less than the car's range.

Wh per mile means you're mostly multiplying instead of all the dividing we do, and puts the trip length in the priority position.
 
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It's possible that a better battery chemistry will come out eventually, but who is taking battery technology seriously besides Tesla?

Anyone who wants to make a smartphone or tablet. Folks like Apple and Samsung have a lot more to gain from incremental improvements in battery technology, and a lot more margin to make it happen.

I'll be shocked if a new battery technology reaches mass market in the EV market before it is deployed in phones/tablets (unless it requires an inconvenient temperature range or very tight temperature control that isn't practical in a phone.)
 
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but it's somewhat useful in persuading the unwashed masses that EVs are worth looking at.
The ends justify the means, eh ? ;-)

I have yet to find utility in MPGe if a gasser is compared to an EV:
It says nothing about relative fuel costs;
It says nothing about relative tailpipe emissions or CO2 pollution

And if you want a cheap laugh, read how people mangle MPGe in plug-in hybrids. E.g., C&D, which has still not figured out that electricity consumption should be included in hybrid mode.
 
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The ends justify the means, eh ? ;-)

I have yet to find utility in MPGe if a gasser is compared to an EV:
It says nothing about relative fuel costs;
It says nothing about relative tailpipe emissions or CO2 pollution

And if you want a cheap laugh, read how people mangle MPGe in plug-in hybrids. E.g., C&D, which has still not figured out that electricity consumption should be included in hybrid mode.
I disagree. The Model 3 is 130 MPGe or more than double that of a Prius. In our area gas for a Prius is $.047/mile and the Model 3 is $.021. So the Model 3 has less than half the fuel costs of Prius. Right in line with what you expect from MPGe.
 
I think yo
I believe "vampire drain" is the price you pay for an EV that will outlast most other EVs. Battery management costs a little bit of electricity, but likely results in a battery back that will retain 90+% of it's range after 300K-500K miles. Well worth it, IMHO. The Leaf has little to no vampire drain... and very little longevity as a result.[/QU I have monitored my RWD Model 3 vampire drain over many hours and it appears to be quite repeatable (numerous firmware updates along the way) and it is about 1.2% (3.7 miles?) per 24 hours. The measurements have been made this summer in Austin TX with the car in my very hot garage - many days over 100 degrees F. If I left the car for 30 days I would lose about 111 miles so unless I was driving to an airport and it was 100 miles away it doesn't seem like this would be an issue. To me this amount of vampire drain is just not much of an issue. While I agree it would be great if there was no vampire drain what it is currently for my car certainly wouldn't change my choice of vehicles. Since my car just upgraded to firmware .32 I am starting a new four day vampire test and if it significantly changes I will update this thread.
 
Anyone who wants to make a smartphone or tablet. Folks like Apple and Samsung have a lot more to gain from incremental improvements in battery technology, and a lot more margin to make it happen.

I'll be shocked if a new battery technology reaches mass market in the EV market before it is deployed in phones/tablets (unless it requires an inconvenient temperature range or very tight temperature control that isn't practical in a phone.)
Companies like Apple and Samsung have no incentive to produce better batteries. Battery degradation is preferable when selling consumer electronics because people buy them much more often than a vehicle.
 
I disagree. The Model 3 is 130 MPGe or more than double that of a Prius. In our area gas for a Prius is $.047/mile and the Model 3 is $.021. So the Model 3 has less than half the fuel costs of Prius. Right in line with what you expect from MPGe.
That is a happy coincidence.

The MPGe of a car does not change with the price of fuel.
Glamisdunner has reported that he pays up to 13 cents a mile ( 52 cents a kWh) to fuel his Model 3 in Escondido, CA, or about 2.5x what a Prius would cost. Does that mean the Model 3 in his area has an MPGe of ~ 20 ?

And for the reverse, I fuel up our car with PV that costs about 0.5 cents a mile. Is my MPGe about 550 ?

I suppose we could ask for a window sticker that says "MPGe: 20 -- 500. YMMV"
That should about cover it.
 
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The best example I know of that shows the nonsensical results that come of MPGe is this,
The Long Ranger, a petrol generator towed behind a Toyota RAV EV

View attachment 328042

Given:
1. The thermo efficiency of petrol to electricity in the towed generator is quite a bit less than the therm conversion of petrol to mechanical in a Petrol RAV.
2. Conservation of energy still rules

Result: A gallon of petrol will push a petrol RAV further than a gallon of petrol in the Long Ranger.
Guess which car has the much higher MPGe ?

Presumably the rating applies to the car, and does not take into account where the electricity comes from. With any EV, the source of the electricity is a factor. I've read, though I cannot cite a source and don't know the accuracy of it, that even a coal-fired power plant is cleaner and more efficient than a car's gasoline engine, because of issues of scale. Natural gas is cleaner than coal. Wind, solar and hydro are cleaner than both.

But calculations of MPGe cannot realistically take into account the source of the electricity because it's so different in different places, and even between a home with solar and one without.

We need a system for comparing efficiency between gas cars and EVs. Average cost per mile would be one way, but MPGe avoids having to consider regional cost differences.

Anyone who wants to make a smartphone or tablet. Folks like Apple and Samsung have a lot more to gain from incremental improvements in battery technology, and a lot more margin to make it happen.

I'll be shocked if a new battery technology reaches mass market in the EV market before it is deployed in phones/tablets (unless it requires an inconvenient temperature range or very tight temperature control that isn't practical in a phone.)

Yes.

Not sure why my post "posted" into sreams post?

Check the placement of the quote and unquote tags. If those are in order, I've occasionally had a glitch where the cursor jumped to a different spot, deleted a chunk of text, and started typing there. If I catch it in time the Undo button in the Edit menu can restore the lost text and I can resume.

Good argument for proofreading before posting.