Charging an hour cost at home?

[stew18]

New Tesla guy here,

Sorry if this is a repeated question but I did look at previous posts with no luck. I’m sure it’s here somewhere.

I purchased a Model 3 LR and when charging at home I had my electrician change a 220 outlet that was set up for a welder to a NEMA 14-50? I think that’s right? I currently am getting about 33 miles per hour of charge.

I live in Washington State and I pay an average of 10 cents per KWh. All I want to know is what it is costing me an hour to charge at home? Seems like a simple question but I have gotten anywhere from 5 cents to 50 cents an hour as an answer.

Any correct answer would be welcome

Thank you

 

[GtiMart]

I believe you are pulling 32A from your 14-50 plug, at 240V. (it's not 220... ). Multiply 32A x 240V and you get 7680W, or around 7,5kW (watts are volts times amps). If you pay 10 cents per kWh, it means it costs 10c if you use 1kW during 1 hour. You are using 7.5kW, so you are paying around 75c for one hour of charging.

 

[ZilWin]

I believe you are pulling 32A from your 14-50 plug, at 240V. (it's not 220... ). Multiply 32A x 240V and you get 7680W, or around 7,5kW (watts are volts times amps). If you pay 10 cents per kWh, it means it costs 10c if you use 1kW during 1 hour. You are using 7.5kW, so you are paying around 75c for one hour of charging.

And you can verify the exact numbers by looking at the Charging screen while the vehicle is charging it will display the actual voltage and amperage. You can then use those numbers to do the arithmetic GtiMart described.

 

[stew18]

I believe you are pulling 32A from your 14-50 plug, at 240V. (it's not 220... ). Multiply 32A x 240V and you get 7680W, or around 7,5kW (watts are volts times amps). If you pay 10 cents per kWh, it means it costs 10c if you use 1kW during 1 hour. You are using 7.5kW, so you are paying around 75c for one hour of charging.

GtiMart,

Thank you for your quick response. I appreciate the correction of 240v from 220. Electricity is very confusing for me to understand and really I don’t feel safe changing the batteries in my TV remote .

I have always hated math story problems so your very thoughtful and relatively easy answer brought back some high school PTSD

Anyway, if i am getting approx 33 mph of charge and we’re to charge it from 0% to 100% it would be about 8 bucks, give or take.

thanks for dumbing this down - it really does help

 

[Kimmi]

STATS tells me it costs $0.06 for every added mile to my 2021 LR.

 

[stew18]

STATS tells me it costs $0.06 for every added mile to my 2021 LR.

STATS? You must pay more in Cali? At .06 that comes out to $21 a charge. Does that seem right? Again, I am only good at math if I’m typing the right numbers in my calculator

 

[jjrandorin]

GtiMart,

Thank you for your quick response. I appreciate the correction of 240v from 220. Electricity is very confusing for me to understand and really I don’t feel safe changing the batteries in my TV remote .

I have always hated math story problems so your very thoughtful and relatively easy answer brought back some high school PTSD

Anyway, if i am getting approx 33 mph of charge and we’re to charge it from 0% to 100% it would be about 8 bucks, give or take.

thanks for dumbing this down - it really does help

If the goal was to figure out how much a "full tank" costs you, a LR tesla model 3 has (very very roughly) a 75kWh battery pack. Since your electricity costs is a nice round number of 10c a kWh, 75kWh times 10c = 7.50, or $7.50, roughly. Brand new model LR Model 3s have slightly more than 75kWh (probably like 80-82) so yeah $8 to go from 0-100%

The cars display "miles" but thats for our convenience. It doesnt charge in miles, it just does a conversion to tell us a number on the screen for a given charging rate. So, it will cost you between 7.50 and 8 to go from 0-100, but you will usually not be doing that, nor will you actually be getting "33 miles" from "33 miles added" to the vehicle, which adds complexity to this for sure.

STATS? You must pay more in Cali? At .06 that comes out to $21 a charge. Does that seem right? Again, I am only good at math if I’m typing the right numbers in my calculator

California electric costs will be from 15-16 kWh cents for "super off peak in the middle of the night 12midnight to 6am) to more than 50 cents a kWh from 4-9pm under some plans... so yes, our cheapest electricity is significantly more than you pay, and most people out here are probably paying an average of 30-40c a kWh when its all added up.

That same full tank for an average californian is likely 15 (cents a kWh) X 75 = $11.25, to somewhere around $37.50 (50c a kWh X 75), depending on when they charge, if they are on a time of use plan, etc. This still works out cheaper than gas, because our gas is likely much more than yours, too. Premium unleaded is like $4.55 a gallon right now around me, while regular unleaded is 4.25 a gallon right now.

Gas buddy says that regular unleaded is 3.19 a gallon in washington state right now. That means for a 15 gallon tank of regular gas, where you are is $51.04 on average, and where I am, for the same thing, is 63.75, or, enough to fill up your model 3 daily with just the difference.

Conversely, its bright and sunny out here most of the time, which is why so many people are getting solar.

 

[stew18]

I believe you are pulling 32A from your 14-50 plug, at 240V. (it's not 220... ). Multiply 32A x 240V and you get 7680W, or around 7,5kW (watts are volts times amps). If you pay 10 cents per kWh, it means it costs 10c if you use 1kW during 1 hour. You are using 7.5kW, so you are paying around 75c for one hour of charging.

New guy here with a follow up question,

it appears most of you are well versed in all things Tesla so here goes another charging question.

if I charge to a certain percentage a get a message that says this is a bad idea on a continual basis or something like that.

Of course I do t want to damage my battery but I did see someone tweeted (is that the right word?) Elon asking if it was bad on the battery to charge to 100% and he said it wasn’t at all and that he just decreased the regenerative breaking?

Where is the truth here?

thanks again

 

[stew18]

If the goal was to figure out how much a "full tank" costs you, a LR tesla model 3 has (very very roughly) a 75kWh battery pack. Since your electricity costs is a nice round number of 10c a kWh, 75kWh times 10c = 7.50, or $7.50, roughly. Brand new model LR Model 3s have slightly more than 75kWh (probably like 80-82) so yeah $8 to go from 0-100%

The cars display "miles" but thats for our convenience. It doesnt charge in miles, it just does a conversion to tell us a number on the screen for a given charging rate. So, it will cost you between 7.50 and 8 to go from 0-100, but you will usually not be doing that, nor will you actually be getting "33 miles" from "33 miles added" to the vehicle, which adds complexity to this for sure.




California electric costs will be from 15-16 kWh cents for "super off peak in the middle of the night 12midnight to 6am) to more than 50 cents a kWh from 4-9pm under some plans... so yes, our cheapest electricity is significantly more than you pay, and most people out here are probably paying an average of 30-40c a kWh when its all added up.

Conversely, its bright and sunny out here most of the time, which is why so many people are getting solar.

Thank you for the confirmation. I was to figure out how much to fill it. It is about 95 miles to work and I use about 110 to 120 charged miles. So at about 6 bucks for a round trip I’m doing good. That was costing me 35 to 40 in gas.

is there an app or something I can get that will tell me how much usage I am using out of that one outlet?

 

[Kimmi]

STATS? You must pay more in Cali? At .06 that comes out to $21 a charge. Does that seem right? Again, I am only good at math if I’m typing the right numbers in my calculator

SCE charges $0.25/kWh

 

[Rocky_H]

if I charge to a certain percentage a get a message that says this is a bad idea on a continual basis or something like that.

Yes. Take a look at the charging limit screen. See where it has those two sections designated? 50%-90% is marked as "DAILY". And 90%-100% is marked as "TRIPS". If you charge in that TRIPS area for a few days in a row, it will show you that warning, because that is unhealthy and damaging for the battery to use that a lot. Sometimes you need that extra range, so use it sometimes as needed, but not constantly.

Of course I do t want to damage my battery but I did see someone tweeted (is that the right word?) Elon asking if it was bad on the battery to charge to 100% and he said it wasn’t at all and that he just decreased the regenerative breaking?

Where is the truth here?

The "truth" is that Elon Musk does have to sell cars.
So he isn't going to tell people to NEVER use above 90%. I kind of recall that Tweet, but it was about telling people to not be afraid of using a full charge sometimes if they need it. It's still definitely damaging to do that constantly for your daily charge. The main thing lithium ion batteries don't like is sitting at the top or bottom end a lot of time.

 

[Jeremy3292]

82/0.85*0.13 = $12.54 to fully charge from 0% to 100%

Model 3 LR has an 82 kWh battery pack / 85% charging efficiency (15% lost) * $0.13 cents per kWh (my local cost) = answer.

 

[Frank99]

Where is the truth here?

thanks again

Simple answer:
Lithium-Ion batteries degrade just a little bit every time you charge to 100%, or discharge below 10%. Tesla recommends that you set your everyday charging limit to 90% to minimize this degradation, but tell you not to fret about charging to 100% if you need to for a trip. Seems like good advice, and you can probably expect 250,000 miles out of your battery pack if you follow it. Of course, you may only get 200,000 miles if you disregard it and charge to 100% every day.

I'm an engineer and have done a lot of reading on this subject. As a result, I set my normal charge limit a bit lower at 80% because of the heat here in Phoenix, and plug in before the car gets below 20%. On the 5 or 6 road trips I do a year, I have no problem charging to 100% - but I find that I seldom do. From where I am, there's little to no advantage in doing so because of the locations of the Superchargers - charging to 100% doesn't let me skip one. I have no problem drawing the battery down to 10% or lower (pulled into one Supercharger with less than 1% left on the battery), but I generally charge enough at the previous SC that I arrive with 10-20% battery at the current SC.

Don't sweat it too much. People around here can get all wrapped around the axle about precisely how to manage the battery to maximize it's lifetime, but the truth is that the battery will last longer than you've probably owned any other car in your lifetime.

 

[jjrandorin]

New guy here with a follow up question,

it appears most of you are well versed in all things Tesla so here goes another charging question.

if I charge to a certain percentage a get a message that says this is a bad idea on a continual basis or something like that.

Of course I do t want to damage my battery but I did see someone tweeted (is that the right word?) Elon asking if it was bad on the battery to charge to 100% and he said it wasn’t at all and that he just decreased the regenerative breaking?

Where is the truth here?

thanks again

The discussion on battery health, charging percentages, etc is in this thread:

Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

Yes this is normal. It is possible the estimate is off a little and the actual rated range is something as high as ~330 rated miles, but generally speaking capacity loss like this is normal. You have a BMS-estimated 71kWh. How many miles on the odometer? It will likely be quite slow from...

teslamotorsclub.com

if you have further questions on that topic (range, battery health, etc) please post them in that thread. Thanks.

 

[Gasaraki]

Would would just charge to 80% everyday if you don't need the range. 90% and over are for long trips.

 

[stew18]

Simple answer:
Lithium-Ion batteries degrade just a little bit every time you charge to 100%, or discharge below 10%. Tesla recommends that you set your everyday charging limit to 90% to minimize this degradation, but tell you not to fret about charging to 100% if you need to for a trip. Seems like good advice, and you can probably expect 250,000 miles out of your battery pack if you follow it. Of course, you may only get 200,000 miles if you disregard it and charge to 100% every day.

I'm an engineer and have done a lot of reading on this subject. As a result, I set my normal charge limit a bit lower at 80% because of the heat here in Phoenix, and plug in before the car gets below 20%. On the 5 or 6 road trips I do a year, I have no problem charging to 100% - but I find that I seldom do. From where I am, there's little to no advantage in doing so because of the locations of the Superchargers - charging to 100% doesn't let me skip one. I have no problem drawing the battery down to 10% or lower (pulled into one Supercharger with less than 1% left on the battery), but I generally charge enough at the previous SC that I arrive with 10-20% battery at the current SC.

Don't sweat it too much. People around here can get all wrapped around the axle about precisely how to manage the battery to maximize it's lifetime, but the truth is that the battery will last longer than you've probably owned any other car in your lifetime.

Thank you my friend I appreciate you taking the time