Can It Be This Simple?

[Beasts]

Just visited our S in the garage to check a few things and noticed the synopsis of our most recent charging session. On the right hand side of the screen in front of the driver one line was "Gained +41kW Hr." Hadn't noticed that before but I decided to take that number and multiply it by our cost/kWHR and came up with $4.47 for a 130 mile trip. About the price for a gallon and a half of regular gas. The trip was mostly at highway speeds (62 to 76 mph) at a temperature of around freezing using mostly the seat heaters. The charger was set to the same maximum % setting just before and after the trip. Never saw that bit of information mentioned in the Owner's Manual but it sure is nice to check fuel consumption in dollars and cents. Maybe this is just common knowledge to most of you but it was a pleasant surprise to me.

 

[GtiMart]

If you really wanted to be precise, you'd need to measure the energy from the wall as there are charging losses. Looking at the gain in the battery doesn't account for that. At least you are accounting for other energy expenses idling in park, that sort of thing, which I think is good. As a rule of thumb, I think you can add 8-9% to that for a reasonable charging loss on 240V at a reasonably high Amp setting at home. To be more precise you'd need the precise charging efficiency.
If you're not a geek like me then what you're doing is enough

 

[Beasts]

If you really wanted to be precise, you'd need to measure the energy from the wall as there are charging losses. Looking at the gain in the battery doesn't account for that. At least you are accounting for other energy expenses idling in park, that sort of thing, which I think is good. As a rule of thumb, I think you can add 8-9% to that for a reasonable charging loss on 240V at a reasonably high Amp setting at home. To be more precise you'd need the precise charging efficiency.
If you're not a geek like me then what you're doing is enough

Just so that I am understanding this correctly, are you saying that the losses occur after the current enters the wall charger or after it enters the car? The charging seems to occur consistently at 48 Amps. Is this loss primarily in the form of heat? Not that I don't believe you but it sure is frustrating to think that the charging loss is that high. Sometimes, like it or not, the truth is a real bummer. I try to be precise.

 

[OxBrew]

Just so that I am understanding this correctly, are you saying that the losses occur after the current enters the wall charger or after it enters the car? The charging seems to occur consistently at 48 Amps. Is this loss primarily in the form of heat? Not that I don't believe you but it sure is frustrating to think that the charging loss is that high. Sometimes, like it or not, the truth is a real bummer. I try to be precise.

If you're not at IDK 70° outside, there's some energy going to heat the batteries a bit, and small parasitic loads to run the minimum internal charging controls on board the car during charging.

I don't care. I used to plug in block heaters all the time on ICE cars, warm them up, gas on a really hot day has a lot less density than the middle of winter per gallon.

All that noisy junk is a wash in my opinion.

 

[GtiMart]

I believe most is lost in the conversion from ac to dc, votage adaptation, and that happens in the car (onboard charger).. But I am not an expert. Others will explain it better.

Battery heating is a separate thing, spending energy actively to heat the battery. That should only happen if the battery gets close to freezing.

 

[roblab]

Just charge it up and enjoy the drive. No matter how you slice it, you're paying from half to a fourth on electricity compared to what you used to pay for gasoline. In other words, way less. It doesn't do any good to advertise these numbers to the general public, especially the macho truck owners, as it just makes them mad that they aren't smart enough to save money on fuel. They get around this lack by cussing out electric vehicle owners and throwing rocks at their cars (yes, that's exactly what happened). Oh, and by the way, my car is way prettier than their big truck, and I probably can carry just about everything they carry by pushing it into my car, which has about 60 cubic feet of storage (Have you seen the "basement" under the trunk floor??) ... compared to 50 cubic feet in a Ford F150 (don't know how they measure that). Plus, my load doesn't get wet.

 

[Beasts]

Just charge it up and enjoy the drive. No matter how you slice it, you're paying from half to a fourth on electricity compared to what you used to pay for gasoline. In other words, way less. It doesn't do any good to advertise these numbers to the general public, especially the macho truck owners, as it just makes them mad that they aren't smart enough to save money on fuel. They get around this lack by cussing out electric vehicle owners and throwing rocks at their cars (yes, that's exactly what happened). Oh, and by the way, my car is way prettier than their big truck, and I probably can carry just about everything they carry by pushing it into my car, which has about 60 cubic feet of storage (Have you seen the "basement" under the trunk floor??) ... compared to 50 cubic feet in a Ford F150 (don't know how they measure that). Plus, my load doesn't get wet.

Can't help but see the "basement" since I still don't have a trunk floor! And I'm sure you're not forgetting much less maintenance, much quieter and a whole lot faster and better handling. But, lest I forget, it doesn't have the noise that makes it macho. The sacrifices we make.
As far as the charging figures, it just helps me feel better to have the numbers. I have no problem loving the car, the numbers just give me the science to remind me that there are real solid, rational, environmental factors to compliment my enjoyment, my emotions. Yeah, I think that about covers it.