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Talk me into 100A wiring vs 50A wiring

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I guess I'll have to find an electrician who's willing to do the full load calculation. For the three EVSE installations I've had done in the past, none of them cared about anything beyond whether there was space for the breaker, lol.

We do have two totally separate HVAC zones to run, which cuts into the capacity quite a lot. If I have to, I'm sure we could survive even with 50A split between the two wall connectors using the power sharing feature. Not ideal but we'd survive, since I don't have a commute and my wife doesn't drive a whole lot.
You can do your own residential load calculation; there are numerous worksheets on line (like this one). I used this, and it agreed with what my electrician later did. BTW, upgrade to 400 A service is not necessarily cheap, but it does improve the value of your house and allows for additions of later loads without having to stress about power availability. In my case, Alabama Power even upgraded the line between my house and transformer at no cost to me (see complete story here).
 
Quite frequently I see people on the side of the road (and sometimes in the middle of it) that have run out of gas. I also see people with dead cell phones that can never find their USB cord. I fear that for those even a supercharger in the garage won't solve their lack of situational awareness.
 
I suspect "forget to plug in" is ICE-speak. EV owners I know routinely plug in where ever they find a free plug and also routinely plug in every day at home. Not once has anybody I know ever reporting having "forgotten" to charge. In ICE, sure, because one must stop at a gasoline station somewhere. BEV's are another world. I notice PHEV including Porsche, routinely plugging in when visiting locations such as, for example, Whole Foods. Has anybody here ever "forgotten"?
Yes, forgetting to plug in is a real thing. I do it about every other month. However, forgetting to plug in when you're low on charge doesn't happen because you're aware of the charge level and the consequence of forgetting. I've never forgotten when there would not be enough charge for the next day's usage.

The comment above about Situational Awareness is right on point. People who run out of gas will also have problems using an EV. The problem is the operator, not the equipment.
 
Let me see...
After about 6 years of electric car ownership, there have been three times that I have come out to the car and found it unplugged with about 9 miles of range. I blame myself.
But, I simply plugged it in, and then swiped my wife's ICE car. Since my wife goes off to work about 2 hours after I do, and since my wife's place of business is considerably closer (*and* there are charging stations in the parking lot there), there was no catastrophe.
It was a minor inconvenience, but I still didn't like it.

-- Ardie
Oops. I still need my own keychain to get into the office.
 
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I got my HW2 Model S car right before Christmas. After talking to a few other Model S owners I decided the 72 amp charging upgrade shouldn't matter for me so I declined that upgrade. I used the portable charger on a 14-50 outlet for 3 months. Two weeks ago, I replaced the 14-50 receptacle with the HPWC. Its nice knowing the charger in the trunk. I would have done a few things differently in hindsight but they are relatively minor issues and are really something to fix the next time I move to a new house.

The portable charger maxes out at 40 amps, the HPWC goes to 48 on HW2 cars without the upgrade. Charging 20% faster with a little bit of planning is a nice bonus and well worth it.

If the run from the main is short I would definitely have it wired to be future proof: wire for 100 amp service, either for faster charging to handling two cars at once in the future. The next best choice is to wire it for 60 amp service so you can charge at 48 amps with the HPWC. If you are going the 14-50 route I would tell the electrician to wire it to code for 60 amp service and just have a 50 amp breaker installed. This will leave you the headroom needed to replace the outlet with a HPWC and at least get 48 amps out of the HPWC after swapping out the breaker.

If the run is long and you are trying to be cheap, you can use a 6-50 adapter and outlet. This run excludes the neutral line and should save some money, but you won't be able to wire this up to a 14-50 in the future, but installing the HPWC in the future will work fine.

The run from the main to the outlet was on the same wall in my garage, around 600$ for a 14-50 install.
 
Walking and taking the bus serve my needs :)
...with significant daily and weekly inconvenience. That is a far cry from this way of thinking you are espousing where someday, maybe, possibly, it's conceivable that you might potentially want this, so EVERYONE should spend this extra money for it. You might, potentially want to move a set of furniture someday, so you should have a U-Haul truck as your daily driver year round, because that might come up, right? I recommend Thomas Stanley's books The Millionaire Next Door and The Millionaire Mind. One of the traits about them is that they have money because they have the wisdom to not constantly waste money on things that aren't useful for them, as you are recommending.

Your overgeneralizations aren't helpful. Some people have very short daily driving use (ours is about 20-30 miles most days). Some people have small sized electrical systems for their houses(our house is 125A main breaker), so the cost to get a 100A line is really high. Some people have a Supercharger very nearby, so even this hypothetical rare "quick turnaround" charging scenario is covered and doesn't require high speed charging at home.
 
So here's my dilemma... I have a Model S showing up in a month or so which will only have the 48A charger, and I have a Model 3 hopefully showing up sometime later this year that I'm assuming will also be a ~48A car. These charging rates will meet my needs easily, since I rarely drive more than about 100 miles in a day. I've survived just fine with a LEAF and a 20A EVSE.

I have two wall connectors ready to install, and the nerd in me wants to just max them out with 100A wiring to future proof things. This will of course be more expensive and more complex to install. I'd need to run conduit for the wiring since NM isn't an option, and I'd have to architect it all around Power Sharing since I can't run two individual 100A circuits from my total 200A household service.

For 50A wiring I could just run some 6/2-NM through my crawl space and be done with it. I'd get 40A to the car vs. the max of 48A, but I'm sure I could live with that just fine.

Is there any reason at all to bite the bullet and install for 100A? Barring any future cars being massively LESS efficient, I just don't see a reason for me personally.

Is my logic sound? :)

Why not just run two seperate 50A circuits to each Wallconnector. You'll have the benefits of the simpler wiring and the combined charge rate is almost the same.
 
If it serves your needs, it's not a compromise.

It's all about time. How much is your time worth to you.

I lived in a suburb and worked in a downtown building. At first because my company subsidized it I took the train and light rail so I wouldn't have to deal with traffic. The problem was I still had to drive a very busy highway to get to the train station, then all the waiting for trains and waiting for the next light rail car...assuming there were no outages or train crossing issues. Finally after getting the worst Flu I've ever had (probably from the train) I decided to start driving and rented a parking spot in a close by garage. When I started driving it my commute to work went from 1.5 hours to 1 hour and the commute home went from 2.25 hours to 1 hour. It cost me more in gas and the parking fee, but I saved around 2 hours a day on average in commute time.

When you're talking about charging you're talking about the cost of time. Most people are probably good with the 48amp charger and a ~30amp J1772 or a NEMA 14-50 outlet with the UMC. Some (probably very few, but still) people will be good with a regular 120V outlet. For others that want more freedom of time they would pay the extra money for a HPWC with a 100amp circuit and upgrade to the 72amp charger in the car. Personally when I order my car I will order the 72amp charger and a HPWC with as large as a circuit as I can install because I think my time is worth that quickness. Most of the time I may drive 10-15 miles a day, not even every day but on the odd chance I need to drive all over the metroplex I want the convenience of charging as quickly as I can. Maybe when the supercharger next to the Ballpark and AT&T stadium is done I'll reevaluate my choice but that would be limited for me as well because I won't have unlimited supercharging.

Just some random thoughts.
 
Quote from the electrician was $4,500
Are you saying the marginal cost to install 100 amp instead of 50 amp is an additional $4,500?

Yes get another quote. As any discussion of the choice between 50 amps and 100 amps is meaningless without discussing the marginal cost.

I have found the marginal benefit to having a 100 amp line connected to an 80 amp hpwc plugging into a Tesla with dual Chargers that can receive 80 amps and therefore charge at 56 miles per hour has been helpful on many occasions after coming home with a fairly empty battery and then having to go out on another trip within a few hours right away.

I always plug in and always charge to 90% as fast as possible to minimize the chance of ever being caught needing to make a long drive with < 90% battery.
 
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If time or variability was the issue, I would spend my money on a Chademo adapter before going up in amps. Then you are ready for anything in your region, anywhere you need to go.

My .02
I tend to agree, since I used to have a LEAF and used Chademo quite a bit to top off quickly when I needed to around town. Not having the option built-in seems like a bit of a step backward to me personally.

For now I've mounted one of the wall connectors in place of my old J1772 EVSE, and have it set to charge at 40A on my existing 50A circuit. As expected, it's more than adequate for my driving style. I think I'm well situated for the time being, until the Model 3 arrives.
 
I suspect "forget to plug in" is ICE-speak. EV owners I know routinely plug in where ever they find a free plug and also routinely plug in every day at home. Not once has anybody I know ever reporting having "forgotten" to charge. In ICE, sure, because one must stop at a gasoline station somewhere. BEV's are another world. I notice PHEV including Porsche, routinely plugging in when visiting locations such as, for example, Whole Foods. Has anybody here ever "forgotten"?
Yup, I forgot to plugin my Leaf once (I blame how much of a "pain" it is to plug in vs. the Tesla). I was screwed the next day, and had to unexpectedly work from home. My wife needed the Model X to drive carpool, so we couldn't swap.

As for plugging in everywhere I go... ick. I don't want to show up to work an hour early to compete with all the other Leafs and C-max and Fusion PHEV guys for the few plugs (pulling out the 120v EVSE) in the parking garage. Maybe if we had a J1772 that wasn't open when I pulled up I would. But in general I feel like it's a huge pain to plug in anywhere except for at home (and Superchargers on road trips). I bought EVs for convenience and freedom from needing to refill!
 
I recently got an 8TB HD. For the first time ever I believe that I should have saved a few dollars and gotten a smaller one. Since I don't save much video this one will never come close to getting filled.
Heh. I have 4 8TB drives. Two are completely full, and two are at about 50%. Actually, I have 8 of them. Still need to get around to setting up the backup of the primary four!
 
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