Free unlimited supercharging vs (paying for) installing charger at home...

[dewittbo]

This is my experience: When I originally got my X, I thought I would just use the free chargers on the campus of the university where I work. Fortuitously, there were two (on the same pole) not too far from my office. They only provided 15 miles of juice per hour of charging and I was only allowed to stay hooked up for three hours at a time, but since I live only 10 miles round-trip from work, I figured it would be good enough. That was, until I found it to be a pain to find one of the stations to be free when I needed it, or found it blocked by ICE idiots. The 110 (120) volt plug at home only gave me 3 miles/hour of charge, so a reasonable night of being plugged in would only give me 30 miles of charge, give or take. That kept me worrying about whether I would have enough charge the next day to do extra driving, when needed.

I got tired of worrying about it, so I took the plunge and purchased a 240 Volt, 32 Amp home charging unit from ChargePoint on sale for about $350, then had a friend/electrician install it for $150 (including parts) in my garage, and so for about $500 initial outlay I can now rest easy with 23 mile/hour of charge per night. I don't need to, but I plug it in every night and have a full charge in the morning for about 20 cents worth of electricity. Even a 'full' charge of 200 miles or so is only about $2 worth of electricity. I figure that's pretty good for a little peace of mind. Oh, and the nearest SuperCharger is about 30 miles away.

 

[bg875]

I know “a plugged in Tesla is a happy Tesla”...

But when considering the $ quotes to install a charger at home (I’ve gotten quotes in the thousands given my setup) vs. just using free unlimited supercharging, I’m wondering why this wouldn’t be a viable option if:

1.) you have free unlimited supercharging
2.) you have a supercharger near you (mine’s only 2 miles away fortunately)


Would this be ok to do?

How do you get free unlimited supercharging?

 

[Nguyenning]

Another interesting factor here is that the new referral bonus is 5,000 free supercharging miles that expires in SIX MONTHS. That's a very short time window to use those miles...

Could encourage some people to go to the supercharger more frequently, just to get the most of their referral bonus.

 

[wemetzger]

I have had two home charging situations over the last two years, along with free supercharging:

1) 12v charging using UMC, free electricity in an apartment
2) 60 amp Tesla wall charger.

For both situations, we have relied on Free supercharging. I know alot about what it takes to make free supercharging work! So first, I agree with most people on this thread that say waiting to supercharge your car, or not finding a charger when you really need it are two situations where relying on Supercharging will get real, real old real quick. So, 2 miles from your house is nice.. but the bigger question is, what is near the supercharger where you can occupy your time? If your answer is just one or two things.. it wont work. Being able to "catch up on work" sounds like a solution, but it just wont work everytime.
I'm in a lucky environment. I have one 2 miles away, but 3 others with in a 10 minute drive. So, every time I go to the grocery store, starbucks, take the kids to the park, go to Target, Homegoods, Home Depot, or a restaurant, I have the ability to do those things AT a supercharger. So, I literally waste almost no time supercharging once or twice a week. It is my opinion that the battery degregation is minimal, or at least, is less costly than the electricity itself. I don't feel guilty about taking up a charging spot, as I generally go when there is not a wait, although there was a learning curve here.

When I lived in the apartment, most times it wasn't worth plugging in to get 3 miles per hour, even for overnight, even though it was free. But it did help when we were in a pinch. And it also helped when I knew I wouldn't be driving for awhile... say plug in Friday night when I know Im not driving first thing on Saturday.

Now, I do have a great home charging situation. I am buying a second Tesla and getting solar installed. I do expect that will be charging more and more at home. But for year one we just got i the habit of supercharging, and that has spilled over into year two despite having a home set up.

 

[Spalding]

Unless you've got lifetime free supercharging, the kw/hour rates charged at Tesla Superchargers are almost always higher than what you could get in a regular home environment.
Getting the $ back from installing EV charge plug in a garage pales in comparison to the convenience it provides. Regardless, people quarrel about whether having 220 volt/50 amp EV plug in garage for charging adds to home value when you go to sell. (And that is all you need - the extra $520 to buy a Tesla 60 amp wall charger is unnecessary.) In CA, I've seen EV plugs listed in real estate MLS descriptions, so clearly it's a selling point - maybe small, but it 's not nothing. Maybe not as important elsewhere - so far. But unless your installation quote is truly outrageous, I think you'll get some value back at sale time.
if the complaint is that you have to upgrade an old, underpowered electrical panel to make it work, then I think it's an even stronger case to upgrade & install EV plug. Updated electrical service is absolutely a plus when it comes time to sell. And in the meantime, having an updated, higher capacity panel is useful and much safer.
Also, check with your electrical utility or the state - many offer rebates or tax credits to help cover the cost of installing an EV line.

 

[wemetzger]

Just saw yoru free supercharging runs out in 6 months.... Then yes, for sure do the upgrade. Maybe it doesn't pay itself back, but when you factor in the resell cost and convenience, it seems like a no brainer. Since you have to do expensive work anyways, it probably makes sense to dedicate 60 amps. When you are starting from scratch, the price difference will be almost nothing, and faster is better

 

[Indian King]

Would like to share my experience. Not advice - just my experience and my wonky way of thinking
I booked a model X 100 D March 2018 to be delivered in June 2018. Thought that supercharing was cool and free, so would be easy. The closest supercharger to my home is 18 miles away and so a two way trip would cost me atleast 45 minutes and atleast another hour to supercharge. So I started evaluating mechanisms to charge at home and for me the best option was to buy a wall charger to be able to charge fast should I needed it. So I bought a HPWC ($500 + tax in CA) and started looking around for electricians who could install it. My incoming electrical panel was 125 amps and most of the folks told me to upgrade the panel. Now the cost to upgrade the panel & install the charger was quoted between $1800 - $3500 from various companies. One of them came in saw my requirements and suggested that install a solar system and combine the install to get a 30% federal tax credit and also start getting cheaper electricity. Long story short - I did various calculations on solar capacity and finally got a solar system installed, got the HPWC installed, got a parallel NEMA 14-50 point installed (just in case my wife wanted a Tesla too) and upgraded the panel for $17,600(pre-federal credits- got 30% off, so nett was $12,320). I have already saved $2000 in electricity bills this year and hope to save at least the same in coming years. I have used Tesla supercharging facilities very rarely and do charging at home at night after 10.00 PM when the cost of electricity is the lowest (12 c in summer and 13 c in winter)... I usually charge it to 80% capacity once in 3 days - and that is becuase I forget to put my car on charge and so it turns out that on an average I do this once in 3 days. My HPWC charges the car @ 17KWH per hour and so it usually takes about 4 hours to charge (I do not drain the batterly fully either). Plus the HPWC is very convenient to use and I keep the NEMA 14-50 and the standard J connecter in the car just in case I need to use it somewhere.
So what started off as trying to charge my car at home turned into a very interesting project of going more green than just owning an electric car (though my reason to buy the model X was the fantastic driving expeience) and a much more expensive one. But I would do the same again. ...

 

[Del Schier]

I guess I am pretty handy and the box for my house is next to the garage. A 50A circuit breaker, 3' ROMEX and some clamps plus a box plate and NEMA 14-50 outlet. $37.00 at the Depot!

 

[mike123abc]

I never had free supercharging, but I Supercharge a lot... There is a supercharger less than .5 miles from my office. I have an office HPWC (100 amp). I usually arrive about 7-15% at the office (after driving between my various locations). I supercharge to about 50% and then go to the office and hook up to the charger. I usually have about 3 hours of charging to get to 90%. It costs me $2-$4 to get to 50%. I do it 2x or so a week. The only real reason I do it is so that I am not tied to sitting at the office for hours waiting for charging.

If I hooked it up to the charger at the office and wanted to leave in the next couple of hours I would have to go to the supercharger and charge, but it would be a lot slower since it would be near 40%. 50% will get me home (well actually 35% but I do not like going below 10%), so I charge to about 50% then I am free to leave when I am done.

I own the office so it is not free charging. It costs me about 8 cents per KWH. The supercharger costs me 23 cents a minute, but delivers 120 (now about 150) kwh, so about 12.5 cents (now less) per minute. I figure it is less than 50 cents difference to charge to 50% at the supercharger. Now that 150kwh (today it was 146) it is even less. Well worth it to have the freedom to leave at any time.

 

[H-H-H]

Here's a short version of what I did (my "experience") since getting our MR 3 in Feb. First EV so it was a learning experience.

My wife has free charging at work (Chargepoint stations). However, seems like lots of people actually count on charging at work since many are commuting from far away, so that got tiring really fast with people competing for spaces. We also have a Supercharging site with 26 stations (and I think 10 more "valet" stations) 1.5 mi away and another one 1.9 mi away with 10 stations. Like others have said, I've only gone to those to confirm it really worked when the car was new.

So we started plugging in with the UMC at home into a 120V outlet. Which was fine since it was 4-5 mph and she only drives 40 mi per day. But I didn't feel comfortable since the plug that was near the car was also shared with another appliance and occasionally trip the circuit breaker even if I turned down the charge rate to 3 mph. There was also one time when I touched the wall and it was getting hot, and I noticed some ominous sparking sounds - turned out the old plug was loose. So definitely want to check to make sure you've got a plug that's in good condition and tight connections inside. I agree with others who have said if you're going to use the UMC with 120V/15A outlet, be sure it is located where you don't need an extension cord and it's dedicated.

I began to look into installing a "NEMA 14-50" because that's what I assumed was ideal. Along the way I discovered what others have said, in no particular order:
1) My panels were old (from the '70's) made by "Federal Pacific Electric" (FPE). I had a couple electricians say they were considered fire hazards. Of course I was skeptical and didn't believe them, but after doing some research and reading an IEEE article, at least to me, it seemed a legit concern. So, I decided to get my main panel and subpanel replaced. I wanted to do it right for peace of mind and, god forbid, insurance reasons if I ever filed a claim, so had it permitted and inspected by the city; and if I was going through that much trouble I got the charging option installed and inspected at the same time.

2) I checked two "Tesla recommended" electricians and two I found on Yelp. Long story short, the two Tesla recommended ones were the most responsive (the other two didn't even give me quotes). I'm happy with the work done by the Tesla recommended one, who apparently has installed hundreds if not thousands of EV charging options in the area.

3) Back to the "NEMA 14-50". Because of my particular house configuration (125A service, A/C unit, electric dryer, oven, and size of house), after going through the load calcs it turned out to be code compliant I would need to upgrade service. Of course I thought this would be super easy - just replace some wiring, right? My house has underground service, so it would have required trenching and a long timeline, I was told upwards of $10K (I live in expensive Bay Area, CA). The other option was to install a "DCC" for ~$2K - basically a little box that monitors the load in the house and either allows the charging or not based on a set threshold. To me that was overly complicated, and I know our A/C only comes on a couple weeks a year and never while the dryer/oven are being used. So I wasn't going to do that.

4) Finally, I asked the electrician what circuit my situation would allow. At first he said 240V/20A circuit. Now keep in mind his calcs were based on typical appliances and assumptions since the two Tesla recommended electricians were doing everything through pictures I sent of my panel and garage, etc. But then I went and specifically looked at the loads listed on the appliances, and after that he was able to bump me up to 30A (technically I think we could have gone up to 35 A). I did have my electrician put in wiring to support 50A for potential later upgrade because he said it wasn't going to cost him any more (maybe because they were charging me a lot anyways?). The wiring runs from one end of my garage to the other (subpanel on one end to garage door on the other end).

5) As someone else mentioned, might be worthwhile checking if you local jurisdiction or utility will help pay for a "EV charger". During all of the above, I discovered my utility will pay for "charging hardware" and permit fee up to $750. Something to do with carbon credits in California and was a new program they were rolling out. So I opted to go that route and setting the Wall Connector to 30A; I know this may seem like "overkill" but it works really well for us and I figure if eventually we get a second Tesla, I could connect a second Wall Connector and have them talk to each other.

Long story short, I ended up updating my panels because they were outdated, and installed a Tesla Wall Connector (paid by the utility) while I was at it. I feel safer with the updated panels. The UMC lives in the frunk along with tire repair kit and emergency supplies, so I don't need to remember to bring it on trips, although if my utility didn't pay for the Wall Connector I probably would have installed the NEMA 14-30 and used the UMC, eventually buying a spare to keep in the car.

 

[SparkyB]

Curious what amperage you have your Wall Charger set at?

Note: 6/3 romex (you really only need 6/2 BTW) is rated for 55A. You are allowed to use a 60A breaker, but it's still essentially a 55A Circuit.

If you set your wall charger to 48A that would be 87% of a 55A circuit and would exceed 80% of 55A.

I hope you set your Wall Charger to 40A. Because I can't fully charge my car in 3-4 hours at 40A.

Unless you ran 6 AWG in conduit, that would be overkill and it would be much cheaper easier to use 4-2 AWG and 60 Amp breaker.

I'm just pointing a common misunderstanding with 6 AWG Romex and 60A breakers and Wall Chargers.

For the 60 amp breaker you want to use 80% for the load. or 48 Amps not 55. 48 Amps is the maximum for a 75 kva Tesla Model 3 So 48 Amps and a 60 Amp breaker are correctly matched. #6 wire could be 55, 65 or 75 Amps. You need to derate for the breaker not the wire.

 

[mswlogo]

For the 60 amp breaker you want to use 80% for the load. or 48 Amps not 55. 48 Amps is the maximum for a 75 kva Tesla Model 3 So 48 Amps and a 60 Amp breaker are correctly matched. #6 wire could be 55, 65 or 75 Amps. You need to derate for the breaker not the wire.

No, you need to derate for the wire for a continuous load.

That's where the confusion is. Just because the code allows you to put a 60A breaker on a 55A romex cable (because they don't make 55A breakers) doesn't magically make it a 60A circuit. It still should be treated as 55A for continuous loads. And you should only use 80% of the 55A. Which is below 48A amps. So you have to go down to the next setting on the Wall Connector (40A). This is why I questioned it because unless you put 6 AWG in conduit (which raises it's ratings) it doesn't really make sense to use 6 AWG Romex for a new Wall Connector install. Unless you know your panel is limited and plan to use a 50A breaker. And most DIY installers don't do conduit. So when ever I see 6 AWG and wall connector in the same sentence it raises a red flag, why would someone do that? There are some cases with "surge" type loads that it can be treated like a 60A. But this is continuous load and should not exceed 80% of 55A amps which is 44A (not 48A).

It's beaten to death here.

HPWC on 60amp #6?

 

[Saguarojoe]

True, depending on your need 120 could be a bit slow. But if you are an average commuter...it should be enough.

I also agree that 120 is a good option. Although we are retried we have put 14K on the 3 since last July. Weekends tend to be the heaviest usage so if I can't charge it enough on Sunday night I can catchup by Monday or Tuesday. There is a supercharger three minutes away but I avoid it as much as possible unless topping up for a trip. I have been able to isolate the monthly cost pretty well for 120/15A. It's $20 a month. We do have solar though most of my charging is after the sun sets. I use the supplied Tesla charger and take it with when we travel.

 

[RCMeltzer]

I know “a plugged in Tesla is a happy Tesla”...

But when considering the $ quotes to install a charger at home (I’ve gotten quotes in the thousands given my setup) vs. just using free unlimited supercharging, I’m wondering why this wouldn’t be a viable option if:

1.) you have free unlimited supercharging
2.) you have a supercharger near you (mine’s only 2 miles away fortunately)


Would this be ok to do?

Continual supercharging reduces battery life. My 220v charger, which I also use with my Leaf, cost less than $1000 installed.

 

[dmurphy]

Well, in my situation it’s an older home from
1950s with original electrical. Pretty janky to be honest.

The panel is inside above laundry machine enclosed in a cabinet and is only 100 amps. When we moved in, the inspector had questions about it but it was a “sellers market” so not a deal breaker for us.

Now with the new car, getting the panel and electrical upgraded with a NEMA 14-50 is sort of a 2 birds kinda deal. It’s just a lot of money compared to the alternative of doing nothing to the house and using free unlimited supercharging...

What panel do you have currently? If it's a Zinsco or Federal Pacific, this becomes a different conversation altogether. That's a life-safety conversation, and has nothing to do with the EV at all.

All that said - I installed a Tesla HPWC outdoors for charging my Model 3. I chose the HPWC because I wanted the full 48 amps. As others have said, it's mostly unnecessary, but the majority of the work was installing the conduit, wiring and breaker. My electrician charged me $600 for the install, including an outdoor cutoff switch. So, a couple hundred more bucks for the HPWC was OK with me, for the convenience and outdoor waterproofing.

If, for some crazy reason I wanted to change to a different EVSE, I can dismount the Tesla wall charger and replace it with an outlet or a different EVSE. The hard work is done - that'd take me all of 15 minutes.

I have the wall connector mounted on the side of the house; but then put a 3D-printed mounting "block" on the side of the fence post for hanging the cable connector. This way I don't have to open the gate every time I go somewhere.

 

[vickh]

I agree with @mswlogo on the Nema 6-20 (20 amp - 240 volt) plug. You can use smaller gauge wire and should not overload your current panel. It will add about 10 miles of range per hour to your car. Will need to get a 6-20 adapter from Tesla. On most days you will probably have a "full tank" when you leave in the morning and can skip the wait at a SuperCharger all together.

I used the 6-20 plug for a couple of months and it worked out great.



View attachment 403993

Can you install 6-20 on an existing 110 smaller gauge wire? I have tons of room on my breaker for amps and wiring ready to go for 110 vs having to do house "surgery" with 14-50 We might be moving in a few months so looking for a temp solution thats better then 110

Is 6-20 inefficient compared to 14-50?

 

[MrMassTransit]

Can you install 6-20 on an existing 110 smaller gauge wire? I have tons of room on my breaker for amps and wiring ready to go for 110 vs having to do house "surgery" with 14-50 We might be moving in a few months so looking for a temp solution thats better then 110

Is 6-20 inefficient compared to 14-50?

If it is on a dedicated circuit, yes, you can install a 240 breaker and use a 6-20. Wire is good for both 120 and 240 - what matters is the amount of amperage you are putting over that wire. You need a minimum of 12 gauge wire to install a 6-20.

 

[one true morty]

I have not read the whole thread so I apologize if this was already stated - beware of just 'sitting' at a supercharger. I didn't know that there was such a thing as an 'idle fee'. We were charging and went to a diner nearby and I looked as we were paying and saw that we had more than enough to get home and could then charge for cheaper overnight. We paid and left and got a notification that we had been charged an idle fee as the station was more than 1/3 full (it wasn't. There were 6 bays and only 1 other car charging so that makes it Only 1/3 full). The fee was waved as it was our first one but I didn't know that they were a thing. Just an fyi for those like me that were not in the know. Not sure if it applies to the S w/ unlimited charging though.

 

[Rocky_H]

We paid and left and got a notification that we had been charged an idle fee as the station was more than 1/3 full (it wasn't. There were 6 bays and only 1 other car charging so that makes it Only 1/3 full). The fee was waived as it was our first one but I didn't know that they were a thing.

I do wonder if you misremembered the wording a little bit. It's not 1/3, and hopefully they didn't say that. It's supposed to be 1/2. Here is the page and the wording describing it:
Supercharger Idle Fee
"For every additional minute a car remains connected to the Supercharger, it will incur an idle fee. If the car is moved within 5 minutes, the fee is waived. Idle fees apply when a Supercharger station is at least 50% full, and double when the station is 100% full."

So that is supposed to be idle fees only if the station is at least 1/2 full. However, you have noticed a problem they have frequently had. Whatever sensor readings they are using to get that "information" into their database utterly sucks. It seems that way too often, their support people have a screen in front of them showing that the station is nearly full, when out here in the real world there are tumbleweeds blowing through the 7 out of 8 empty stalls. So--yeah, you shouldn't have been assessed an idle fee at all, since it was less than half full.

Not sure if it applies to the S w/ unlimited charging though.

Yes, it applies to all Tesla model cars. Unlimited charging has nothing to do with it, because this is about when cars are just sitting there, blocking the spots and not charging. No one has a right to unlimited blocking of Supercharger stalls.

 

[one true morty]

How do you get free unlimited supercharging?

You get free charging if you have an S or if you use the special code they give you in your loot box and someone buys a tesla with that code. You both currently get 5k free charging for 6 months. We had an electrician install a 240 am dryer outlet near the driveway and we got that adapter and we run the cord thru the frame of the windows and get 22 m/h charge. It has worked perfectly except on long trips.