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Newbie says hi and home charging question

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Hi all,

I'm a newbie here from San Jose, CA. I made my M3 reservation on 4/1/16. According to Tesla's official delivery estimate, my delivery date is sometime in Q1 next year(for the long range option). So I have some home charging related questions. Apologies if those have been asked before. If there's a similar post or blog somewhere on this forum, please share the link and ignore this one.

I own a town house with a connected two car garage. I share the walls one each side with my neighbors. I have in the unit dryer which I believe it's 240v. But the outlets in the garage are 120v.

1. Do I have to modify the 120v to 240v to charge the model 3?
2. If so what's the cost of getting 240v in my garage?
3. Can model 3 be charged with 120v?

I'm leaning towards the long range option, premium upgrades, 19" wheel, red color and maybe enhanced self driving, but not FSD.

Thanks.

Shaun
 
120v charging is pretty darn slow. It's okay if you don't drive all that far each day. It's definitely worthwhile to get a 240v to the garage for an EV, but you might can live with 120v for awhile if needed and if you don't have too long of a daily commute. On 120v, you will restore maybe 3 or 4 miles per hour of charging. Say you tend to be plugged in for 10 hours each night. That would be somewhere from 30 to 40 miles of range restored each night. Not much. With a 240v outlet, you'll be able to charge more like 20 to 25 miles of range restored per hour, meaning you can pretty much fully charge from empty to full overnight. Now those are Model S numbers. Since the 3 is more efficient, it might do slightly better in each case.
 
I own a town house with a connected two car garage. I share the walls one each side with my neighbors. I have in the unit dryer which I believe it's 240v. But the outlets in the garage are 120v.

1. Do I have to modify the 120v to 240v to charge the model 3?
2. If so what's the cost of getting 240v in my garage?
3. Can model 3 be charged with 120v?
Congratulations on making the move to an EV. You will not regret it.

I went through the same decision process that you are now going through, so let me answer your questions from my viewpoint. Others may disagree, but everyone's circumstances are different.

First some clarifications:
- if you have an electric dryer, I assume it will be on probably a 240v., 30 amp circuit (you didn't say)
- Is your dryer in the garage? (probably not since you said all outlets in the garage are 120v.)
- is your electric panel located in the garage?
- how many miles will you be driving your model 3 per day, per week, per month?

1. You can charge your car on 120v. but you will probably not be happy with the slooooooooow charge rate. If you have a proper 240v. outlet you can charge at 30 miles+ per hour. A proper 240 v. outlet will be on a 50 amp circuit which is much different than a dryer outlet. If you run a 50 amp circuit to a convenient location for charging, then you can have your electrician install a NEMA 15-40 240v. outlet or a Tesla HPWC (High Power Wall Charger). Your electrician will know the terminology. The price will depend on which option you choose, the specific layout of your utilities and can vary from a couple of hundred dollars to 4 figures. You cannot "modify" a 120v. outlet to a 240v. outlet for efficient charging of your Tesla without running new wire to that 240v outlet and the price will depend on your specific conditions and the load size of your electric panel.
2. Again the cost is highly variable depending on your specific layout and only a qualified electrician can make that determination with an onsite examination. I was lucky and all the stars aligned and I was able to have a licensed electrician put in a NEMA 15-40, 240v. outlet for $235. Other people have spent over $2000 to install a 240v. circuit with an HPWC. It varies depending on your utility circumstances, location in the US, and how sympathetic your electrician is!
3. Yes, you can charge at 120v. but only at the rate of about 4 miles per hour of charge. For most people, including me, that is not sufficient. I want to wake up each morning with a charge of AT LEAST 200 miles of range so I want to be charging at 30+ miles per charging hour..

In conclusion, it is difficult to answer your questions without additional information. It is best to have an electrician perform an onsite inspection and give you specific answers.
 
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One would get 20+ miles per hour. Still enough to recover 180-220 miles overnight.
Perhaps you could, but you would be charging in peak rates so results in a higher cost of charging. Back to my point, everyone's circumstances are different, therefore it is difficult to give a definitive answer to OP's questions without a lot more information and his preferences. In my case, it was less expensive to put in a new NEMA 15-40 outlet in the garage than running a splitter from the electric dryer which is located in the house. YMMV.
 
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It is possibly to combine two 120v circuits into 240v if you can find two outlets on different phases close enough together. Your outlets in the garage are probably all on the same circuit but you never know.

Your 120v circuits are ether going to be 15 or 20 amps (and will give you roughly 4-5 miles per hour, as others have stated), while a 240v circuit can be anywhere from 30 to 100 amps. For the Model 3 there’s no reason to go above 60 amps (if you get the LR version and install a wall charger). Otherwise a 50 amp circuit is the most you can make use of.

It deserved to be repeated - your final decision should be based on your unique circumstances. Questions you should answer:
  1. How many miles do you drive each day?
  2. How much do you want to spend on a charging solution?
  3. Where is your electrical panel located in relation to the garage?
  4. What size electrical service do you have, and how much is currently utilized?
  5. Do you have space for additional breakers in the electrical panel?
 
An admittedly older study (about a decade old, but the last one I remember seeing) by the Bureau of Transportation Statics shows that over three-quarters of the US population commutes less than 40 miles per day. Providing that you are home (and remember to plug in) for 8 - 10 hours per night, 120 charging is very sufficient.

There could be time of use charges that come into play that may make getting a 240 line run economically favorable, but how much you drive is the main factor.

My wife and I each drive a little over 20 miles round trip to work daily, we have one L1 and one L2 in the garage. Both cars are always ready to go in the morning and we would be just fine with both of us charging at L1, but I like the ability to charge one a bit faster in case we need to drive more than normal in a day.
 
then you can have your electrician install a NEMA 15-40 240v. outlet........................ I was able to have a licensed electrician put in a NEMA 15-40, 240v. outlet
In my case, it was less expensive to put in a new NEMA 15-40 outlet in the garage
In the above quotes, I transposed my numbers. The correct specification is NEMA 14-50 outlet on a 50 amp breaker with proper size wiring. Sorry for any confusion.
 
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Thanks guys! Will look into the NEMA 15-40 outlet in my garage. Very helpful info. I actually posted the same question on the official Tesla.com forum. Somehow, my post got deleted. Never got this many informative information which could help me with my purchase decisions. This is a very nice forum!