Home Charging Speed

[DucRider]

208V is three phase power, at home with a dual legged (or whatever that's called) breaker you get 240V so with your math the numbers would be.

2.40 * 11.5 = 27.6
2.40 * 7.7 = 18.48

Huh?
2.08 is the miles per kWh
The 11.5 (kW) is calculated for 48A @ 240V

Sponsored

 

[Trekkie]

Huh?
2.08 is the miles per kWh
The 11.5 (kW) is calculated for 48A @ 240V

Not a number I'm used to seeing, helps to have the units especially when they can be easily mistranslated since 208V vs 240V is a thing

I'm taking the amount of time it takes to charge and the range numbers on the dash, across the three EVs I have owned it is *always* 25 miles of range when charging 240v @ 32A regardless of the efficiency of the vehicle. Just taking time / range reported by the car. When I was still driving to work they had 208V @ 6A and it adjusted exactly the same ratio accordingly wether it was my Bolt EV or the X.

That's why I'm saying it doesn't make sense how the numbers are derived.

 

[DucRider]

I'm not comparing the wh/mi numbers, I'm stating exactly what the car reports when my charger is plugged into it and how long it takes to charge the battery.

yesterday I charged my Tesla X with a 75kwh battery. it charged for 6 hours 4m, added 152.35 miles of range. that comes out to 25.3 miles per hour.

yesterday I charged my Fiat 500E. It doesn't have fancy data logging like the tesla does, but when I plugged it in it said it'd be charged in 2hr 45m, based on its limited dash information that meant 25 miles in an hour of charging.

Your Model X gets less range per kWh than the 500e, and the R1T will get significantly less than either.

By your theory, all EVs would consume the the same per mile.

I think what you are seeing is although your EVSE is capable of providing 32A @240V (7.68 kW), the Tesla may be charging at a higher rate than the Fiat (6.6 kW)

 

[DucRider]

Not a number I'm used to seeing, helps to have the units especially when they can be easily mistranslated since 208V vs 240V is a thing

I'm taking the amount of time it takes to charge and the range numbers on the dash, across the three EVs I have owned it is *always* 25 miles of range when charging 240v @ 32A regardless of the efficiency of the vehicle. Just taking time / range reported by the car. When I was still driving to work they had 208V @ 6A and it adjusted exactly the same ratio accordingly wether it was my Bolt EV or the X.

That's why I'm saying it doesn't make sense how the numbers are derived.

Wow!
That means my R1T will get 488 miles of range!
It takes 19.5 hours to charge the R1T @ 32A
19.5 hours x 25 miles = 488 miles of range.

Don't know why Rivian isn't letting people know.

EVs don't all get the same range per kWh

Look at the MPGe and kWh/100 miles numbers.

 

[Pherdnut]

Plugging into a vanilla outlet at work should add another 50 miles.

 

[Rhidan]

I'm not comparing the wh/mi numbers, I'm stating exactly what the car reports when my charger is plugged into it and how long it takes to charge the battery.

yesterday I charged my Tesla X with a 75kwh battery. it charged for 6 hours 4m, added 152.35 miles of range. that comes out to 25.3 miles per hour.

yesterday I charged my Fiat 500E. It doesn't have fancy data logging like the tesla does, but when I plugged it in it said it'd be charged in 2hr 45m, based on its limited dash information that meant 25 miles in an hour of charging.

You are comparing the wh/mi numbers. Adding "152.35 miles" in a Tesla X will take less energy than adding "152.35 miles" in a Rivian R1T because it takes more wh per mile to travel that same 152.35 miles in a Rivian.

 

[CommodoreAmiga]

208V is three phase power, at home with a dual legged (or whatever that's called) breaker you get 240V so with your math the numbers would be.

2.40 * 11.5 = 27.6
2.40 * 7.7 = 18.48

"Split-phase" is the term I think you're looking for.
It's two legs of 120V AC (relative to ground) that are 180 degrees out of phase from each other.

208V three-phase has three legs of 120V AC (relative to ground) that are 120 degrees out of phase from each other.

 

[Trekkie]

You are comparing the wh/mi numbers. Adding "152.35 miles" in a Tesla X will take less energy than adding "152.35 miles" in a Rivian R1T because it takes more wh per mile to travel that same 152.35 miles in a Rivian.

Look i don't claim to know what I'm talking about, but that doesn't address my next data point which was that a Fiat 500E with a dinky ass battery charges up to its max range at the same rate, 25 miles of range in 60m of 240v/32a.

It's much more efficient than the X.

I don't have the Bolt any more, but it also would add 25 miles of range in an hour of 240v/32a charging.

it was in the 3.2 miles/kw range that was the number I could get out of it.

even third party chargers have tools that tell you 'per mile' as a metric of charging based on amperage, see here: https://www.chargepoint.com/drivers/home/

that's why I'm so confused by the numbers being used for Rivian, it will definitely take more time as the battery is bigger (132 kwh?) or even more with the max pack in the 180 kw range, but the number of miles seems to be constant across other car manufacturers.

 

[Rivuylkill]

but the number of miles seems to be constant across other car manufacturers.

Think of it like putting gas in an ICE vehicle.

Let's say the pump puts in 1 gallon of gas every hour. No matter what car you put it in or how big that tank is, it gets 1 gallon per hour.

In a prius, that gallon might get you 50 miles, so you get 50 miles/hour.

In a f150, that gallon might get you 17 miles so you get 17 miles/hour.

Electricity is roughly the same, if you put in the same amount of energy/hour but that how that energy converts to miles varies by car.

Also, about consistency across other manufacturers, it's really not consistent it's just close since all the EVs to date are at least within similar ballparks. Just output from a quick google of miles / hour on a nema 14-50 220v charge

Model 3 ~ 30
ID4 ~ 22
Model S ~ 23
Mach E ~ 20
Audi Etron sportback ~ 22
F150 Lightning ~ 13

 

[CommodoreAmiga]

Look i don't claim to know what I'm talking about, but that doesn't address my next data point which was that a Fiat 500E with a dinky ass battery charges up to its max range at the same rate, 25 miles of range in 60m of 240v/32a.

Battery SIZE has nothing (for purposes of this discussion) to do with how much range you get per hour of charging.

You could have a 20kWh or 200kWh battery... 32A of input current will get you the same range-gain-per-hour on both packs. Now the 200kWh pack will take 10x longer to charge, but you'll also get 10x range.

48A @ 240V is 11,520W or 11.5kW. EPA says it takes 480W of from-the-wall power to go 1 mile (accounts for charging inefficiencies) so that 11.5kWh would get you 11,520W / 480W = 24 miles of range gained, per hour.

Your Fiat 500E has an EPA rating of 300W per mile. So the same charger (assuming Fiat can take 48A -- I haven't checked that) would get you 11,520W / 300W = 38.4 miles of range gained, per hour.

At 32A, Rivian would be 7,680W / 480W = 16 miles per hour.
At 32A, Fiat 500E would be 7,680W / 300W = 25.6 miles per hour.

 

[SeaGeo]

(assuming Fiat can take 48A -- I haven't checked that)

It can't. Which explains why it's not flying off the charts at 40+ "mph" charging on level 2.

You'd think Fiat would quote the max charge rate in their manual, but no. "<less than 4 hours" on a 240v charger with a 24 kW hour batter. So roughly speaking I'd assume it's limited to 25A and 6 kW.
A little more googling and I'm seeing 6.6 kW quoted.

At 84 miles of range for the U.S. variants, and 4 hours of charging, that's about 21 miles per hour.

 

[Trekkie]

I think the fiat woud inflate like a balloon and float off if you tried to do 48a. Good thing the charger in the car determines the amps.

it is a great teenager learning to drive car. They can’t get to far, it doesn’t do fast charge so if they run it down it’s 3 hours on 240v. But boy the guys at fiat really hated evs and just shoved the engine in there. Was bummed the new one didn’t come to the US it really is a fun go cart to drive.


though in truck country you sure feel like you’re gonna be a hood ornament some days.

 

[TheSasquatch]

Man all of these fancy calculations and talking about Fiats and Bolts...

..but could some just please tell me whether I need to purchase the $500 wall charging appliance in order to charge at the higher rate? My Model 3 just needs the [included] cord with the NEMA adapter. Rivian isn't telling us what the heck is included but is pushing the purchase of the wall appliance.
Do I need it if I have a NEMA 1430 in the garage already for my Tesla?

So crazy how many threads I've scoured with all of these fancy calculations but no one just simply answers that question

Thanks fellas (and womens)

 

[SeaGeo]

Man all of these fancy calculations and talking about Fiats and Bolts...

..but could some just please tell me whether I need to purchase the $500 wall charging appliance in order to charge at the higher rate? My Model 3 just needs the [included] cord with the NEMA adapter. Rivian isn't telling us what the heck is included but is pushing the purchase of the wall appliance.
Do I need it if I have a NEMA 1430 in the garage already for my Tesla?

So crazy how many threads I've scoured with all of these fancy calculations but no one just simply answers that question

Thanks fellas (and womens)

They include the mobile charger. I don't remember amperage, but they quote about 16 mph for the rivian. So about 7 kW at 32amps roughly.

 

[TheSasquatch]

They include the mobile charger. I don't remember amperage, but they quote about 16 mph for the rivian. So about 7 kW at 32amps roughly.

So if I want the 25mi/hour I have to buy the $500 wall appliance? What does that do that the cord and internal charger in the truck not generate on their own? I was kind of thinking the wall charger was just a gimmicky thing that allowed you to use the app to control / status things.
So most people have the wall appliance included in their order? Tesla doesn't need the big dumb wall appliance to get a faster charge. Weird.

Sponsored