[Speculation] Model 3 0.237 kwh/mile!

[KarenRei]

As pointed out in the other thread: you're not so much paying for power as paying for amortizing the $100-175k supercharger.

And yes, their power will be industrial rates, but it'll also be time-of-use linked, and they'll have high service fees because of the high, unpredictable, inflexible peak power draws.

 

[scaesare]

Doesn't matter. You put some amount of energy into the car from the wall. Then some amount leaves to propel the car. There are losses everywhere.

This is true if you are specifically considering what comes in and out of your outlet. The overall amount of energy consumed includes any losses due to call IR, etc...

However, that's not what the car reports. It's measuring overall power deliver outside the cell, and thus the numbers that are used for mileage and energy usage reporting by the car what the battery delivers to the car.

This is also how a cell is rated. A given amount of power at a specific current is drained from the battery. That amount of energy delivered externally by the cell is what's measured. Given that IR losses vary with current, this will always be a nominal rating, in that the usage will vary. But the point is that a cell/pack is measured by the power it produces. Often time manufacturers do this at a rather low current level to maximize the rating.

If the cell itself stores 15Wh of energy, but loses 1Wh as a result of internal IR, it's rated at 14Wh, not 15. Thus if a pack has a theoretical energy storage of 80KWh, yet only delivers 75 at the measurement test case current draw, then it's a 75KWh pack. The car doesn't suddenly draw more energy, the pack simply can deliver less.

However the car's power monitoring on the dash displays, the drive train, any accessories, etc... all only see the effective power the pack delivers.

So, for energy calculations from the wall, sure, IR/pack losses matter. But so do charger losses. And the energy lost in the cabling of your HPWC. And the cabling from the charge port to the chargers Etc... none of that has a bearing on how efficient the car is at moving down the road, hence my statemen that it doesn't "directly play in to the power/mileage efficiency of the car."

 

[Reciprocity]

Induction motors are better over a wider operating range. PM motors are more efficient within a narrow range.
Tesla may surprise with a new hybrid type motor, we shall see. Probably not tonight though

We know these are the same motors used in the Semi, does that lend any hints into the form that any improvements might be taking. Something that would be good for a very large vehicle. Tesla would make a different motor for the Semi if the model 3 or S motors where less then ideal.

 

[Reciprocity]

$0.2/kWh is actually pretty cheap compared to other fast charging. Here, electricity is about $0.1/kWh at home, while you pay $0.3/minute for 50 kW CHAdeMO. Even assuming you manage to utilize it fully, that's $0.36/kWh, but usually a small EV can only utilize it like 50% on average over a charging session, which means it's closer to $0.7/kWh. And with a cold battery, it can be much worse.

The charging companies *really* don't want you to think they're selling electricity. They would like it if you think of them as selling mobility.

It also varies based on where you are at. It will also go down if they add solar to more Superchargers.

 

[Reciprocity]

I'm on ComEd's RTTP ( real time pricing) program even though I have Solar. Look where my Cursor is at 1AM. Its 1 cents per KWH. You should get on the RTTP program. Its free for everyone. Otherwise you will be charged the ALL day average + $.03 per KWH.

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You should get on the RTTP program. Its free for everyone. Otherwise you will be charged the ALL day average + $.03 per KWH.

Yeah im in that program. You are not adding in the transmission (delivery) costs or other fees. Take your main bill and divide the total paid by the total KWh consumed. You can also download your green button data and see by half hour increments. I pay about 10.6c on average and I am in the same RRTP program and its RRTP btw, not RTTP.

 

[TIppy]

I guess you missed that note about the kwh prices don't include your personal capacity charge. Those charges are include in fixed-rate costs but not in hourly. So the hourly rate is what you pay in addition to your capacity charge.

 

[Reciprocity]

Ok ok. I was just quoting the Price of Electricity. I have solar. I haven't had a bill nor any delivery nor any other costs for 4 years. I need to be charging ComEd delivery charges.

Awesome.. mine is getting installed soon, I cant wait. RRTP is a great program, average is 16c in my area and I have been paying 10.6c for the last 18 months. Huge savings for really doing nothing but trying to lower usage during the day and shift it to the night.

 

[Garlan Garner]

Yeah im in that program. You are not adding in the transmission (delivery) costs or other fees. Take your main bill and divide the total paid by the total KWh consumed. You can also download your green button data and see by half hour increments. I pay about 10.6c on average and I am in the same RRTP program and its RRTP btw, not RTTP.


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If you produce More electricity that you use - via solar....you don't have any of those charges. I forgot.

 

[scaesare]

Are you sure about that? I don't think that's correct. I'm pretty sure the inverter is used for regen.

That's part of why the Renault Zoe has fast charging - it uses the drive unit inverter for charging, instead of having a standalone charger.

The inverter indeed.

The early Roadster based on the A/C Propulsion design had a charger/inverter design that used some common components, so in that sense one could say any regen involved the charger, but it's not been that way for some time.

 

[AWDtsla]

However, that's not what the car reports. It's measuring overall power deliver outside the cell, and thus the numbers that are used for mileage and energy usage reporting by the car what the battery delivers to the car.

The car severely underreports actual consumption. This is a bug, not a feature. Certainly not any basis for an argument, nor is anything you posted after this.

Your argument is similar to someone trying to argue that all gasoline that gets sprayed into cylinder that exceeds stochiometric ratio should not be counted against fuel consumption, since it didn't actually get burned by the engine to produce power. So why count that gasoline? Why count the electrons that got lost as heat inside the battery? Didn't make it to the motor, durrrr!

Dumbest thing I heard on the internet today. So far.

 

[scaesare]

The car severely underreports actual consumption. This is a bug, not a feature. Certainly not any basis for an argument, nor is anything you posted after this.

Your argument is similar to someone trying to argue that all gasoline that gets sprayed into cylinder that exceeds stochiometric ratio should not be counted against fuel consumption, since it didn't actually get burned by the engine to produce power. So why count that gasoline? Why count the electrons that got lost as heat inside the battery? Didn't make it to the motor, durrrr!

Dumbest thing I heard on the internet today. So far.

Your insult aside, the fact is true. What is measured by the car (and not only displayed on the dash, but what the BMS reports via CAN, which is significantly more accurate) is what comes out of the pack, which is after IR losses.

You analogy fails, in that the issue is not energy lost within the motor/drivetrain we are talking about. This is more akin to a gasoline tank.

All gasoline tanks deliver less fuel to the engine than is supplied to the tank. There are evaporative losses (which are minimized), as well as to limits of the pickup tube to get every last drop. It's not 100% efficient at delivering all all gas to the vehicle. So too, no battery delivers 100% of the input energy.

So certianly from the perspective of what you pump such losses are included. From the perspective of the energy efficiency of the drivetrain/aero/rolling resistance, etc... the distance it can travel on a gallon of gas it consumes doesn't change.

That's my point with the battery, the losses it incurs internally doesn't somehow magically change the efficiency of the drivetrain's ability to move the car down the road. THAT was my point.

Otherwise in the same way that a gasoline tank that might suffer more evaporative losses if you let it sit a week would seem to have worse gas mileage, so too a battery that was left to self-discharge for a week would seem to have less efficiency.

 

[KarenRei]

I've not been taking part in this debate, but I have to side with scaesare. If we want an analogy to a gas tank:

Production: energy wasted in producing electricity vs. energy for petroleum production, petroleum distribution, and refining

Product distribution: grid losses vs. energy to distribute gasoline to stations and loss of fuel (evaporative, spillage) in the process.

"Wall" to vehicle losses: charger / wiring / pack / parasitic losses vs. evaporative losses at the station and spillage

Storage losses: parasitic drain and self discharge vs. evaporation over time

Vehicle to wheels losses: parasitic losses and losses in the wiring/inverter/motor/geartrain vs. internal combustion losses (including incomplete combustion) + (somewhat higher) geartrain losses.

For ICE vehicles you generally don't give two MPGs (pump to tank vs. tank to wheels) because the numbers are so similar, while for EVs there's more of a distinction. But if you're measuring pack to wheels, pack capacity is measured as if you had connected a watt meter to a short circuit on the pack. What's happening inside the pack doesn't matter.

 

[ItsNotAboutTheMoney]

I think Tesla will need to do variable pricing eventually, but probably not at the start. Apartment dwellers in LA need to be discourage from charging at 9pm on a hot day.

It would make a big difference here.
Augusta and (the future) Freeport are in CMP (Southern Maine) area.
Brewer is in the Emera (Northern Maine,) area.
Emera is significantly more expensive than CMP.

 

[TIppy]

Pack capacity does depend on what's going on inside. As the power delivered increases, more of the stored energy is dissipated in internal resistance. The capacity will be greater at low power draw vs high. The efficiency is Rload / (Rload + Rbattery).

As for the efficiency outside the battery, a battery with a higher internal resistance will require more current to be drawn to deliver the same power if the batteries have the same open circuit voltage. Power losses increase with current squared.

 

[Reciprocity]

I've not been taking part in this debate, but I have to side with scaesare. If we want an analogy to a gas tank:

Production: energy wasted in producing electricity vs. energy for petroleum production, petroleum distribution, and refining

Product distribution: grid losses vs. energy to distribute gasoline to stations and loss of fuel (evaporative, spillage) in the process.

"Wall" to vehicle losses: charger / wiring / pack / parasitic losses vs. evaporative losses at the station and spillage

Storage losses: parasitic drain and self discharge vs. evaporation over time

Vehicle to wheels losses: parasitic losses and losses in the wiring/inverter/motor/geartrain vs. internal combustion losses (including incomplete combustion) + (somewhat higher) geartrain losses.

For ICE vehicles you generally don't give two MPGs (pump to tank vs. tank to wheels) because the numbers are so similar, while for EVs there's more of a distinction. But if you're measuring pack to wheels, pack capacity is measured as if you had connected a watt meter to a short circuit on the pack. What's happening inside the pack doesn't matter.

This is all very smart and detailed but I am a very simple person. If gas could be as cheap as Solar + EV, it would be. So since it isnt, means it cannot. Market forces would have driven the costs down if they could be driven down after 100 years of gasoline, you should be seeing about as efficient in terms of production as you are ever going to see. Certainly there could be some minor improvements as you see with fracking, but for all intense and purposes, gas prices will not go down much and more then likely will rise. Now electricity will continue to go up in cost as well, but not for those with Solar and places where renewables dominate. At some point you hit a tipping point and the de facto prices always go up will start to become prices going down for a long period of time until they hit the point of diminishing returns with Solar and wind and batteries at nearly 100% market penetration.

But even if Gas and EV had the same cost per mile. EV would still be better because EV are much cheaper to maintain and as battery prices come down, much cheaper to manufacture. I think the number is around $100/KWh at the pack level. Once it goes bellow that number, the EV is cheaper to manufacture because they are much simpler. I should clarify that they are much simpler once you have the technology, which contributes greatly to the $100 price. Its hard to have one without the other. You need a great BMS and really efficient inverters and motors. But these things are simpler then to manufacture once you have the technology, compared to an Ice power train. That is not to discount or say that those things are easy to invent and to make work extremely will. But once you have them, the marginal cost to build the EV would be cheaper at that point then the ICEv. Also, the batteries can continue to get cheaper and the ICEv has already hit a point of diminishing returns where technology can make them cheaper to build.

 

[scaesare]

Pack capacity does depend on what's going on inside. As the power delivered increases, more of the stored energy is dissipated in internal resistance. The capacity will be greater at low power draw vs high. The efficiency is Rload / (Rload + Rbattery).

Agreed, hence my point earlier:

The car doesn't suddenly draw more energy, the pack simply can deliver less.

Pack capacity is what's affected.

 

[JeffK]

This is all very smart and detailed but I am a very simple person. If gas could be as cheap as Solar + EV, it would be. So since it isnt, means it cannot. Market forces would have driven the costs down if they could be driven down after 100 years of gasoline, you should be seeing about as efficient in terms of production as you are ever going to see. Certainly there could be some minor improvements as you see with fracking, but for all intense and purposes, gas prices will not go down much and more then likely will rise. Now electricity will continue to go up in cost as well, but not for those with Solar and places where renewables dominate. At some point you hit a tipping point and the de facto prices always go up will start to become prices going down for a long period of time until they hit the point of diminishing returns with Solar and wind and batteries at nearly 100% market penetration.

But even if Gas and EV had the same cost per mile. EV would still be better because EV are much cheaper to maintain and as battery prices come down, much cheaper to manufacture. I think the number is around $100/KWh at the pack level. Once it goes bellow that number, the EV is cheaper to manufacture because they are much simpler. I should clarify that they are much simpler once you have the technology, which contributes greatly to the $100 price. Its hard to have one without the other. You need a great BMS and really efficient inverters and motors. But these things are simpler then to manufacture once you have the technology, compared to an Ice power train. That is not to discount or say that those things are easy to invent and to make work extremely will. But once you have them, the marginal cost to build the EV would be cheaper at that point then the ICEv. Also, the batteries can continue to get cheaper and the ICEv has already hit a point of diminishing returns where technology can make them cheaper to build.

I like the thought, but the first part is unfortunately untrue. Gasoline has been artificially priced for years. Even with that, you can still buy a gas car with a range greater than the longest range Model 3, enough gas to last the life of that car and all maintenance for less than the cost of solar plus EV (plus additional electricity or battery storage depending on your setup).

I'm hoping the price of solar comes down in the not too distant future. Once the price of solar and batteries comes down then it'll be a no brainer and far superior to gas I agree.

 

[EchoDelta]

What are your disagreements about.
Its always strange when people disagree with you - with no explanations.

Agree it's worth explaining.
I disagreed with your stance of the implications $usd 0.20 / kWh . (Note I didn't flag as wrong, as you clearly stated subjective opinions, vs fact, and didn't generalize, thx).My subjective stance is that it seems a price that is still valuable, fair+ethical.

 

[JeffK]

My subjective stance is that it seems a price that is still valuable, fair+ethical.

Not fair/ethical if they are claiming that the fees aren't for profit... In my area $0.20 per kWh would mean they were jacking up the price 500%.

I understand charging near residential rates because they have to pay for their infrastructure and maintenance but beyond that would be profit.

@Garlan Garner is a little spoiled because he's lucky enough to have solar . But for the rest of us poor saps, we have to pay normal rates.

Here in Indiana they have to charge by minute. Under 60 kWh is $0.08 per minute. The higher the power then the less I pay.

 

[kingjamez]

Not fair/ethical if they are claiming that the fees aren't for profit... In my area $0.20 per kWh would mean they were jacking up the price 500%.

I understand charging near residential rates because they have to pay for their infrastructure and maintenance but beyond that would be profit.

It's not profit until they amortize the cost of the SC install.

-Jim