You pre-ordered a Tesla Model III, so what, do you have a Plug?

[Ciaopec]

I'm buying a house so I can house and charge my future Model 3. I might as well live in in it too.

Live in the house or the M3? Living in the M3 is an unknown though apparently the MS is quite comfortable: You Can Sleep In The Trunk Of A Tesla For $85 A Night On Airbnb

 

[jonnyg]

Wait -- do you mean to say that the M3 will only be electric?!? I can't put gas in it?!? No way, I had no idea! I'm gonna cancel my reservation then.

Towing package + trailer + portable gas generator = problem solved. Just can't drive while charging.

 

[Yggdrasill]

By buffer, I think he means add enough battery energy for 13,500 driving miles per year. But actually at 4 miles / hour, which is the practical charge rate for 120 V and 15A, you get 12,000 miles per year (4 miles / hour x 10 hours per day x 300 days).

If the use of the word buffer was what threw him off, I can explain more accurately.

The goal of charging isn't necessarily to go from zero range to full range overnight. The goal is to have sufficient range for your specific needs at any given time. Suppose I have a 40 mile round trip to work. This means that if I arrive at home at 6 pm on sunday with 25 miles remaining, and need to leave for work at 6 am monday, I need to have at least 40 miles of range. So I plug it in, and get 47 miles overnight, bringing the range up to 72 miles. I go to work, and arrive home at 6 pm again, with 32 miles remaining. Again I plug in, and by 6 am tuesday, my range has increased to 79 miles. This back and forth continues through the week, and on friday evening I have 60 miles remaining. Say I manage to charge for 40 hours in the weekend until monday at 6 am, and I only drive 20 miles, that brings the range back up to 228 miles.

If a person is comfortable with it taking close to a week to get full range after arriving home from a long trip with close to no range, 110V 15A is fine. If range is uncomfortably low, one can also visit a supercharger for 15 minutes and you'll have a nice range buffer. Or on the long trip one can plan the trip so that range isn't completely depleted by the time one arrives home.

Personally, I am fine with my 230V 16A setup. I don't expect that I will ever need more than that. It means that if I get a Model 3 with 80 kWh battery pack, I can at most fill up around 40% overnight, but that's fine with me.

 

[BluestarE3]

No need to worry about any of these electrical outlets and tethered charging solutions. By the time the Model 3 comes out, electric power will be transmitted wirelessly over the air from the next generation Superchargers directly to your car. These are Tesla cars after all, are they not?

Here's a spyshot I found of the next gen Supercharger prototype:

 

[JeffK]

Live in the house or the M3? Living in the M3 is an unknown though apparently the MS is quite comfortable: You Can Sleep In The Trunk Of A Tesla For $85 A Night On Airbnb

This probably depends haha... When 'the fiancee' becomes 'the wife' anything can happen. I may find myself sleeping in the Model 3 inside a garage. Depends what I've done wrong... but I may just do it to get away.

 

[Petra]

What, "WHAT"?

110V 15 amp is 1.65 kW, or 16.5 kWh for every 10 hour charging session. With 350 Wh/mile including charging losses, that's 47 miles. 300 charging sessions means 14,143 miles. (20 W x 365 days/year x 24 hours/day) / 350 Wh/mile = 500 miles of vampire losses per year. The total is exactly 13,643 miles.

Though, it occurs to me now that in the US you derate by 20%. So, I guess 15A is actually 12A. That means that a 15A plug is only good for 10,800 miles per year, given the described charging pattern.

One more tidbit to add to that: charging at 240V is only about 87% efficient, with 120V being even less efficient than that (can't recall the 120V numbers for the S... I recall it being around 75% for the Leaf at 120V).

 

[Az_Rael]

One more tidbit to add to that: charging at 240V is only about 87% efficient, with 120V being even less efficient than that (can't recall the 120V numbers for the S... I recall it being around 75% for the Leaf at 120V).

A very good point. A person would need to look at the costs over time from the charging losses vs the install costs of the higher amperage charging.

For a simple install in a newer house with room in the breaker, it might make long term sense to put in a Level 2 charger. But if the project gets complicated (long runs, panel upgrades, etc) then just paying the charging loss costs for 110V probably makes more sense.

 

[WileyTheMan]

Well, I have a house so I figure I have plenty of time to install a 240v/40a circuit somewhere outside. Even if I get totally lazy, there's always the venerable 110v plug. Gets the job done.

 

[DrivingTheFuture]

Just got my quote a few days ago... future proofing my garage for Model X and Model 3



"Pam Carrier
Jul 22 (6 days ago)

to me

Morning Jordan,
The electric car circuits will cost $285.00 each
Do you want 1 or 2 switches for the paddle fan roughs.
The print shows the chandliers in the dining room & breakfast room so we are good there already."

 

[Petra]

A very good point. A person would need to look at the costs over time from the charging losses vs the install costs of the higher amperage charging.

For a simple install in a newer house with room in the breaker, it might make long term sense to put in a Level 2 charger. But if the project gets complicated (long runs, panel upgrades, etc) then just paying the charging loss costs for 110V probably makes more sense.

Well, I was bringing it up because it significantly lowers the annual miles charged numbers that Yggdrasill posted... but, yes, the efficiency difference is something that may also be worth considering from a long term costs standpoint.

That said, the reason I was suggesting a 240V 30A outlet as a minimum for 100% use case coverage is because it gives you overnight SOC recovery for longer local trips or distance travel. Sure, 120V charging will cover you for short around town stuff (I charged my old Leaf on 120V for a little over two years before I got around to finishing my home-built 240V EVSE project), but it becomes an issue whenever you decide to really use the range that a Tesla provides. For me, examples would include occasional trips down into LA, over to Santa Clarita, or pulling back up to my daily charge level overnight after getting back from a trip up to San Jose (the last Supercharger stop on the way home is usually either Buttonwillow or Tejon Ranch). Charging at 24A on a 30A 240V circuit is just enough to bring my 70D up to nearly 90% overnight, after rolling in at around 20% or thereabouts.

Toss time of use electricity metering into the mix and charging times become much more important, as keeping your charging limited to the super off-peak EV charging rate window is essential for minimizing cost.

 

[AZ Desert Driver]

I've got a few bids to install my home plug. Cheapest 50 amp is $1600. A nice 100 amp into a sub panel is $2200. Add a HPWC and I'm $2600. This back calculates to about a year and a half of driving my ICE. Buying a Tesla to save money is elusive. Now I have to figure I'm saving the world - but not cash.

 

[ABCCBA]

@AZ Desert Driver How far is the run for your circuits? My 14-50 cost $350 installed with parts. My 80A for the HPWC was $450 with parts plus $750 for HPWC.

"Buying a Tesla to save money is elusive." Now that is probably the funniest thing I have heard on this forum. Thanks for the real chuckle. There is no cost justification for a Tesla. 'Pure Vanity' and/or 'Tree Hugging, Save the Planet' purchase.

I've got a few bids to install my home plug. Cheapest 50 amp is $1600. A nice 100 amp into a sub panel is $2200. Add a HPWC and I'm $2600. This back calculates to about a year and a half of driving my ICE. Buying a Tesla to save money is elusive. Now I have to figure I'm saving the world - but not cash.

 

[Az_Rael]

I've got a few bids to install my home plug. Cheapest 50 amp is $1600. A nice 100 amp into a sub panel is $2200. Add a HPWC and I'm $2600. This back calculates to about a year and a half of driving my ICE. Buying a Tesla to save money is elusive. Now I have to figure I'm saving the world - but not cash.

Yikes, why are you looking at 100Amps? That seems like overkill.

I suppose if you came home from a trip on an empty battery and only had 4 hours before you needed to drive another 200 miles without Supercharger access, but that has got to be an edge case.

 

[Petra]

I've got a few bids to install my home plug. Cheapest 50 amp is $1600. A nice 100 amp into a sub panel is $2200. Add a HPWC and I'm $2600. This back calculates to about a year and a half of driving my ICE. Buying a Tesla to save money is elusive. Now I have to figure I'm saving the world - but not cash.

Well, you're still in a better situation than my in-laws... They've been eyeing the Model X ever since we got our Model S and they've just got an old NEMA 10-30 dryer outlet in the garage that's only supposed to be used when the house air conditioner is off (they switched to a gas dryer when they installed central air conditioning). We charge using that outlet and the Tesla Mobile Connector whenever we're visiting and it has been working out fine. Adding any additional outlets or overhauling the existing outlet for anytime use would require a panel and service upgrade, which has been estimated at somewhere around $10k-$20k (the house is on 100A service and has all electric appliances, aside from the gas dryer).

I think I paid $350 for the 240V 30A circuit I had installed for my home-built EVSE project. I would have probably gone for a 50A circuit had we been seriously considering a Tesla at the time, but that would have also forced me to move away from relays and into contactors for the project and those can do weird things to nearby I2C runs... and they cost more.

 

[AZ Desert Driver]

My install needs about 50 feet of trenching, or going overhead and penetrating my garage roof. I NEED only 50 amps today. But I figured that someday I might want to instal a HPWC or a second 14-50 ...and why have to trench again when I just need a bit bigger wire. How big? I added 50 amp twice, but perhaps I should only ask for 80 amps ...but most of the cost is labor.

 

[AZ Desert Driver]

Well, you're still in a better situation than my in-laws... They've been eyeing the Model X ever since we got our Model S and they've just got an old NEMA 10-30 dryer outlet in the garage that's only supposed to be used when the house air conditioner is off (they switched to a gas dryer when they installed central air conditioning). We charge using that outlet and the Tesla Mobile Connector whenever we're visiting and it has been working out fine. Adding any additional outlets or overhauling the existing outlet for anytime use would require a panel and service upgrade, which has been estimated at somewhere around $10k-$20k (the house is on 100A service and has all electric appliances, aside from the gas dryer).

I think I paid $350 for the 240V 30A circuit I had installed for my home-built EVSE project. I would have probably gone for a 50A circuit had we been seriously considering a Tesla at the time, but that would have also forced me to move away from relays and into contactors for the project and those can do weird things to nearby I2C runs... and they cost more.

I'd pull the trigger immediately if it was any figure less than $500. Now, I design, and sharpen my pencil and bargain with the spouse. Need now, future plans and back to the need.

 

[Az_Rael]

My install needs about 50 feet of trenching, or going overhead and penetrating my garage roof. I NEED only 50 amps today. But I figured that someday I might want to instal a HPWC or a second 14-50 ...and why have to trench again when I just need a bit bigger wire. How big? I added 50 amp twice, but perhaps I should only ask for 80 amps ...but most of the cost is labor.

That makes sense. Better for future non-Tesla EV capability. FYI, the HPWCs can be hooked together and supposedly two of them can share 1 circuit to charge two Teslas. Not sure of the details behind that, but that may be a possibility as well.

 

[ABCCBA]

A. Future Proof so that no additional electrical work is needed - New HPWCs can be daisy chained (Master/Slave) from one circuit. Once you own a BEV, you will most likely convert to all BEV so multiple BEVs can be charged off of the same circuit

B. Time-Of-Use Utility Rates - In some parts of the country, it costs significantly more to use power at certain times of the day. So, with a small window of low energy costs, some people would need a faster charging rate.

C. In some areas of the country, commuting to and from work is not a 20 mile round trip and there is not the luxury of Superchargers on the route. Therefore, working 8 - 10 hours with a hour commute back home, does not give much time to recharge before the next use.

D. With the Model 3 low entrance price, a new consumer will enter the picture. That consumer is the one-car family. So, As one partner arrives home, the other is off an going again. So while each trip may be short in distance, there are many throughout the day. Long charging times would potentially lead to a stranded driver with not enough charge to get back home. Or, once home, not enough time to fully recharge.

E. How many times has a person/family decided to hop in the car a go somewhere on the spur of the moment. Can't happen if you are charge on a 120V/15A circuit and you need 10 hours (12KWh) to 50 hours (60KWh) to fully recharge it.

Yikes, why are you looking at 100Amps? That seems like overkill.

 

[MP3Mike]

I've got a few bids to install my home plug. Cheapest 50 amp is $1600. A nice 100 amp into a sub panel is $2200. Add a HPWC and I'm $2600. This back calculates to about a year and a half of driving my ICE. Buying a Tesla to save money is elusive. Now I have to figure I'm saving the world - but not cash.

Don't forget that you might qualify for tax credits. I think the federal is 30%, up to $1,500, and Oregon is 50%. (So 80% of the cost is covered for me.) The only issue is that I don't think it is possible to get the $7,500 for the car and the 30% for the infrastructure in the same tax year. So it is best if you can either install the charging equipment the year before, or after, you buy the car.

 

[Yggdrasill]

One more tidbit to add to that: charging at 240V is only about 87% efficient, with 120V being even less efficient than that (can't recall the 120V numbers for the S... I recall it being around 75% for the Leaf at 120V).

I included charging losses. Assuming 75% efficiency, my estimated 350 Wh/mile leaves 262 Wh/mile in the car. This is entirely realistic in a car that's probably the most aerodynamic car ever mass produced and that is much lighter than the Model S.

Looking at it like this, if the battery pack is (the expected) 55 kWh total, 51 kWh available, the range would be 194 miles with a consumption of 262 Wh/mile. We know the EPA rating will be 215 miles or greater.