110/120V Charging - some questions

The Model S has two different adapters it can use to charge from 120v sources. From a regular 15A breaker, it will draw 12A. If in a relatively warm garage (like 60F), that will get you about 3.5 miles of range per hour. You can boost that significantly if you have, or can install, a 20A breaker circuit that terminates in a NEMA 5-20 receptacle. Then you can use their 5-20 adapter which will draw 16A. This will get you about 5 miles per hour of charge in a warm garage.

Note that charging in a cold environment will reduce charge significantly as the car will use some energy warming the battery.

Note that most people would have 12 to 15 hours of charging time available to them every day.

Why is 120v your only option?

@Cosmacelf has answered most of the OPs questions very well, as usual, I just want to comment that many of those questions can be answered by going to Tesla Charging | Tesla Motors and exploring the information offered there.

Yes, the Model S allows you to adjust the amperage drawn during charging; you can control it.

No, you cannot access a history of your charging sessions nor can you export the data as far as I know, though perhaps the "Visible Tesla" app allows that? Search TMC for "Visible Tesla".

Trying to get by on 110V/12A charging for an S is difficult if you drive more than about 40 miles/day and cannot charge at work.

People who use 120 often supplement it with a trip to a quicker charging station on occasion. This really depends on how far you drive every day. If you are like many in my area who drive 50-60 miles on their daily commute, you'd be supplementing weekly (I imagine, I don't charge at 120).

60 * 5 = 300 miles driven on commute.
3 * 10 * 5 = 150 miles added nightly at 120
300 - 150 = 150 miles added from supplementary charging.

Of course, if there is a way to charge at or near work, then it becomes even easier.

theflyer said:

My questions are:

1) What amperage does the Tesla pull when using a 110/120V outlet? Is there any configuration available (e.g. With our Volt, we can select 8 or 12 Amps)?
2) Is there a record kept that I can access online or via smartphone as to the history of my charging sessions on 110/120v? (e.g. Start time, stop time, kWhs pulled)? Is that data downloadable in a format like CSV?
3) If the Tesla is garaged in a relatively stable temperature setting of 50-70 degrees, how many mph can I safely assume the Tesla would add when using 110/120V charging? In other words, if I charge the Tesla on 110/120v for 8 hours, how much range would that add (I know there is some loss to the active battery management system and that is what I'm seeking to understand)?

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1) The car will pull 80% of the maximum circuit capacity. Circuit breakers are designed to permit surges, but not constant operation at 100%. You can select less amperage be pulled (not more) as it's locked out at 80%. Charging off of 110/120 @ 15 or 20 Amps is pretty slow. Keep in mind, preheating or precooling the car will almost terminate all charging activity due to the limited circuit capacity.

2) If you have the App, it will allow you to start and stop charging and monitor the current draw as well as estimated time of completion. If you have an iPhone (not at Android as I've read on the forum), it will alert (audibly and visually) that the car has started/stopped charging.

3) There used to be a table that would show charging (in miles per hour) on the Tesla website, however, I can't find it at this time. You can search this forum as there are some very nice reader contributed lists that show the charging statistics for all levels of voltages and amperage. If I remember correctly, you can expect 5 miles per hour for a 120 @ 15 amps and 6 miles per hour for 120 @ 20 amps. If the battery is kept at a convenient temperature (the 50-70 certainly sounds right), active battery temperature management shouldn't come into play that much.

Here in New England, I've noticed on the car will become "cold soaked" and therefore require a heating of the battery with no charging happening until that cycle is completed. This can range from 15-20 mins to almost an hour with the current draw being 48A. I'm on a 60A 220V circuit and I usually get around the mid 30's in miles per hour of charge when the battery is at a "happy" temperature.

There are several methods of thought regarding using "local" superchargers (assuming you've paid for the supercharging option). Some believe that you've paid for it therefore you should be able to use it no matter where you are (even if it's in your backyard). Others believe it is for traveling only and you should not use your local charger (say at a nearby mall). Tesla does not appear to have a policy either way on use of superchargers. This is for you to determine right vs. wrong. My belief is that if you NEED them use them. Remember, there these are your gas stations. If I were to travel extensively in a day and deplete my range I would plug in at home. Say it were to become necessary to travel later in the day with less mileage than I was planning on driving. The supercharger certainly would be convenient for a quick "top off" to insure I make it back home.

Something else I've noticed myself doing is becoming a patron of those locations with charging stations. I'm right in the middle of two pretty good size malls/shopping centers. One does not have any charging capability and other does. The one that does not is easier to drive around and less busy. I've noticed myself preferring to travel to the one that does have charging facilities more often (depending on what I'm looking for). After all, mall management realizes that it's an attraction to those of us who have "gone green". BTW, as a side note, PlugShare can be your friend as well.

All in all, it's truly the most fun ride going! Anywhere! Ever! Just have a backup plan in the event that you're lacking sufficient charge...

theflyer said:

Update: The forum software pointed me to a number of useful threads. I see that a charge rate of 3ish miles per hour seems reasonable to assume (maybe a bit more, maybe a bit less depending on conditions). However, I'm still really confused as to how to control the amperage. Do you do that by an adapter or onboard software control?

Still need answers to questions 1 and 2.

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The maximum amperage (12) is set by the adapter. You can manually dial it lower in one amp increments.

You may be able to use Visible Tesla to get that kind of information. Otherwise, you can use the trip metres to see what the usage is while driving. Add 10-15% to that number to get the total usage.

One other thing. Get the 85. No one regrets having the extra range.

- - - Updated - - -

And here is the Visible Tesla thread.

@theflyer, you're welcome. One more thought, did you ever consider a kill-a-watt? I thought I remember seeing one that let's you put in your $/kwh and it will automatically tell you the cost...

http://www.p3international.com/products/p4400.html

andydoty said:

@theflyer, you're welcome. One more thought, did you ever consider a kill-a-watt? I thought I remember seeing one that let's you put in your $/kwh and it will automatically tell you the cost...

http://www.p3international.com/products/p4400.html

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From what I've read, Kill-A-Watt isn't robust enough for this kind of application.

You may not need to know the actual kWh used, because unlike the Volt, your a Tesla will almost always be charging whenever it is plugged in. It's unlikely you will ever completely fill the battery at 120V if you drive every day. So could you assume it's plugged in x hours per day and pay on that basis? You can do the calculation for your area but at typical 10 cents per kWh rates a Tesla costs about 15 cents/hr to charge on a 15A circuit (12A charging).

Could you make use of a Quick220? (Turns two 110s into a 220, Quick 220 Systems) Note that this won't on GFI outlets and the outlets need to be on different breakers. Steambrite makes a competing product.

Evbwcaer said:

Could you make use of a Quick220? (Turns two 110s into a 220, Quick 220 Systems) Note that this won't on GFI outlets and the outlets need to be on different breakers. Steambrite makes a competing product.

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I use this in my garage for 220 and it works for my Volt. Not sure how well it would work for sustained use. I believe after 4 hours of continuous draw it dials back to 80%

Are you in California? There is a law here that prohibits a condo association from disallowing installation of an electric car charger. You still have to pay the costs, but the association must allow it.

TexasEV said:

You may not need to know the actual kWh used, because unlike the Volt, your a Tesla will almost always be charging whenever it is plugged in. It's unlikely you will ever completely fill the battery at 120V if you drive every day. So could you assume it's plugged in x hours per day and pay on that basis? You can do the calculation for your area but at typical 10 cents per kWh rates a Tesla costs about 15 cents/hr to charge on a 15A circuit (12A charging).

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This probably makes the most sense. Just track hours you're plugged in, and assume you are drawing 12A*120V=1440W/hr you are plugged in.

The other option is to have an electrician install a kWh meter before the outlet, and read once/month. Might want a locking cover installed, too, so no one can run up your bill.

It's hard for me to grok the board members being anti-EV. I get being pro- or just ambivalent, but I don't really get anti. Unless you work for big oil. But that's a whole 'nother issue.

flankspeed8 said:

I use this in my garage for 220 and it works for my Volt. Not sure how well it would work for sustained use. I believe after 4 hours of continuous draw it dials back to 80%

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The OP's condo association would likely have an issue with the Quick220 (and its other cousins) as it violates electrical code and creates some insurance and liability implications. See the FAQ in my signature, below, for more information.