I know we have quite a few EV owners here and was just currious to know how you charge your vehicles at home. I have a neighbor a few doors away with a Chevy BrightDrop work van and a Tesla model 3 and was rather surprised to learn that they only use a level 1 (120 VAC) charger for both vehicles.
How do you charge at home?
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Hell no. I'm neither an electrician or EV guy but I wouldn't put up with that. Not only is it slow but I know the efficiency is much worse on 120v something like 75% transfer efficiency whereas with 240v it's at least 90% even on the lowest end of the scale.
I'd isolate the receptacles to find all of the ones that are connected to the breaker and swap the breaker out for a double pole to have 240v at the same 15a and swap the specific receptacle for a 6-15. With a little more work I'd pull the wires and run 12 awg or thicker 10 awg wire with a 6-20 receptacle for less resistance
If need be one could easily revert back to a 5-15 and swap the breaker back to a single pole without having to increase the size of the hole in the wall for the larger 30+ amp receptacle.
I'd isolate the receptacles to find all of the ones that are connected to the breaker and swap the breaker out for a double pole to have 240v at the same 15a and swap the specific receptacle for a 6-15. With a little more work I'd pull the wires and run 12 awg or thicker 10 awg wire with a 6-20 receptacle for less resistance
If need be one could easily revert back to a 5-15 and swap the breaker back to a single pole without having to increase the size of the hole in the wall for the larger 30+ amp receptacle.
I have 3x Autel Maxicharger Lites (240v, 48A, hardwired). They PowerShare with each other to never pull more than 48A total, even when charging 3 EVs at the same time.
I couldn’t imagine charging on 120v. Especially when a 240v circuit is so simple and common.
I couldn’t imagine charging on 120v. Especially when a 240v circuit is so simple and common.
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Patman
Staff member
Charging an EV with a 120v outlet is like filing up your gas tank with an eye dropper 
Tesla charger. Same as we had in Virginia Beach. It charges both NACS (Tesla) and J1772 vehicles.
60A wiring allows for 48A charging at 220 volts.
That’s the maximum possible at home and it yields about 11.5 kW charging. Enough to take a pure EV like a Tesla from dead to 100% overnight.
Stucco repairs from the install pending, but here is ours
60A wiring allows for 48A charging at 220 volts.
That’s the maximum possible at home and it yields about 11.5 kW charging. Enough to take a pure EV like a Tesla from dead to 100% overnight.
Stucco repairs from the install pending, but here is ours
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I have an Autel 48-amp hardwire and a Juicebox 30 amp converted to OpenEVSE. The fka Juicebox is connected to the 30-amp plug I had the builder put in the garage. When our house was constructed in 2015, I knew I wanted an EV eventually, but I didn't know anythig about the different types of plugs, so I just asked for a 240V in the garage without specifying the amperage. When I brought my first EV home (2017 Focus Electric), we didn't have the Juicebox, so we used 120V while waiting for it to arrive. It was winter and it was fairly chilly out, which impacted the range on the vehicle. For the first couple of weeks we just recouped as much as we could each night, then on the weekend we took it an L3 charger to top off. Once we had the charger L2 installed it was smooth sailing. When we got a 2nd EV, I installed the Autel because it was pain only being able to charge in the garage and switching cars was a hassle. The Focus only had 100 miles of range, so it needed to be charged frequently. The Autel is near the front of the garage, so we can charge one vehicle in the driveway and the other in the garage. A 120V plug can work for some if only driving 20 to 30 miles each day.
My usual home charging system is a standard 240 Volt wall plug on a 40 Amp breaker. [A 50 Amp breaker would be better, but hey, you use what you've got.] Using the Tesla Mobile Connector which came with the car and a Tesla 240 Volt connector, my Model 3 will charge at the Model 3's maximum of 32 Amps. But I don't need such rapid charging and have cut the rate back (at the car) for at-home charging to 25 Amps. that system is simple, relatively cheap and it works very well.
People say you should have a high quality (expensive) 240 Volt outlet if you remove the connector regularly. I didn't about know that at the time of installation and as we almost never remove the connector I haven't retrofitted one. How high quality is your electric clothes dryer outlet or your kitchen range 240 Volt outlet, and do you worry constantly about them? Ours are also standard 240 Volt electrical outlets and I never give them another thought.
I've used this system for 5 years (except during driveway repairs). During driveway repairs I only had access to a 120 Volt outlet and long but heavy duty extension cords. That worked adequately well and much better than I expected. I just kept our Model 3 plugged in all the time (which is what I do anyway).
I now routinely charge to only 60% of a full charge (because I think keeping the charge between 40 and 60% of the maximum capacity as much as possible is better for the battery). Most days we use only 5 or 10% of the charge and almost never more than 20%, so a 60% routine charge works well for us. I'm not afraid to charge to 100% and do so for long trips.
People say you should have a high quality (expensive) 240 Volt outlet if you remove the connector regularly. I didn't about know that at the time of installation and as we almost never remove the connector I haven't retrofitted one. How high quality is your electric clothes dryer outlet or your kitchen range 240 Volt outlet, and do you worry constantly about them? Ours are also standard 240 Volt electrical outlets and I never give them another thought.
I've used this system for 5 years (except during driveway repairs). During driveway repairs I only had access to a 120 Volt outlet and long but heavy duty extension cords. That worked adequately well and much better than I expected. I just kept our Model 3 plugged in all the time (which is what I do anyway).
I now routinely charge to only 60% of a full charge (because I think keeping the charge between 40 and 60% of the maximum capacity as much as possible is better for the battery). Most days we use only 5 or 10% of the charge and almost never more than 20%, so a 60% routine charge works well for us. I'm not afraid to charge to 100% and do so for long trips.
In Dec 2018, we started with the Mobile Connector and 120v outlet. 4 MPH.
Shortly after had a NEMA 14-50 recepticle installed to a 50A breaker. Mobile Connector, 25 MPH.
Few years back installed the Tesla Wall Connector, 35 MPH.
Then there is the supply side... I installed solar panels in March 2018 and have a Time of Use (TOU) electric plan.
Each of these charging solutions can work, depending on your use case. By all means, factor the cost of a charger installation into the purchase price of your EV. I also highly suggest checking your EV car insurance prices.
If you use a NEMA 14-50 and Mobile Connector, you do not want to regularly plug in and out. Importantly, get an EV rated recepticle to handle extended high current loads! Here's my neighbor's recent upgrade... Oops!
Here's my solutions over the years. Nuthin' like starting every day with a full tank!
Shortly after had a NEMA 14-50 recepticle installed to a 50A breaker. Mobile Connector, 25 MPH.
Few years back installed the Tesla Wall Connector, 35 MPH.
Then there is the supply side... I installed solar panels in March 2018 and have a Time of Use (TOU) electric plan.
Each of these charging solutions can work, depending on your use case. By all means, factor the cost of a charger installation into the purchase price of your EV. I also highly suggest checking your EV car insurance prices.
If you use a NEMA 14-50 and Mobile Connector, you do not want to regularly plug in and out. Importantly, get an EV rated recepticle to handle extended high current loads! Here's my neighbor's recent upgrade... Oops!
Here's my solutions over the years. Nuthin' like starting every day with a full tank!
@JeffKeryk - you're only charging at 32 Amps? Time for an upgrade!
In all seriousness, the 60A circuit (48A charging rate) in ours is wasted on our XC-90. It limits charging to about 5Kw to preserve battery life, so, about 2 hours to "fill up".
We sized the Tesla circuit at 60A to make it "future proof" - building for the range of cars that might be in our driveway in the future. The labor was the same for a 40A as a 60A, and the supplies (larger wire) were only a minor expense in the installation cost.
In all seriousness, the 60A circuit (48A charging rate) in ours is wasted on our XC-90. It limits charging to about 5Kw to preserve battery life, so, about 2 hours to "fill up".
We sized the Tesla circuit at 60A to make it "future proof" - building for the range of cars that might be in our driveway in the future. The labor was the same for a 40A as a 60A, and the supplies (larger wire) were only a minor expense in the installation cost.
@E365 Is that power sharing dynamic, meaning when one battery fills the other two chargers split the 48 amps equally between them?
@JeffKeryk Is that 32 Amps a built in limitation of your model 3?
32 Amps is the built in charging limit for my 2021 Model 3 SR+.
The 80% continuous limit applied to a 40 Amp circuit can provide those 32 Amps. That's why I used a 40 Amp breaker. But in retrospect a 50 Amp breaker would have been better.
32A is the max with the Mobile Connector that came with the car. That pic is with the Mobile Connector and an empty battery.
The Wall Connector can deliver 48A on a 60A breaker.
I have our Wall Charger set 40A as I recall; the electrician used a 50A breaker
Common settings are: 60A breaker/48A output (11.5kW), 50A breaker/40A output (9.6kW), and 40A breaker/32A output (7.7kW).
At home, the charger is in the car; you supply the juice via the plug.
At a Supercharger, the on-board charger is bypassed and the Supercharger delivers far more.
Got it. I couldn't fathom how a car that can handle 250 kW fast charging couldn't handle more than 7.68 kW of level 2 AC charging.
I've got a Juice box 40 wired for 50 amps (6/3 AWG wire and NEMA 14-50 outlet) but the electrician put it on a 40 Amp GFI breaker. That didn't make sense to this engineer but it works.
I have a NACS to J-1772 adapter in the car now but it looks as though I am going to need the opposite configuration if and when I do go over to the dark side.
Optional TOU billing is a thing here where I live but the rate of adoption has been very low. It may be something to think about should this ever become a two EV household but I am happy where I am for now. Unfortunately I did not consider that scenario when sizing the solar array and may need to go back to the well for more panels.
The solar array sizing is a separate, though intertwined, topic.
When examining our electrical usage, we were guessing, because our usage was based on an unoccupied house and we knew it would go up when occupied. We knew that replacing two HVAC units (out of our three) would greatly reduce consumption. A pure EV would increase it. New pool pumps would reduce it. Guests would increase it. The new mini split in the garage will increase it.
Our usage in April was 2728 kWH. In May, 3799. That’s the result of us moving in and charging the Plug in hybrid as well as warmer weather.
Hard to tell where we will land - so, we chose to maximize the size of the array at 23.8 kW. We can’t fit any more than that without it being visible from the street.
It may cover 100% of our usage. It may not.
But I don’t see our electric use going down much in the future and I certainly don’t see rates going down.
Further, we wanted to establish net metering now. If we’re aren’t grandfathered in the future, we will consider battery storage and time of use rates to see what makes sense.
When examining our electrical usage, we were guessing, because our usage was based on an unoccupied house and we knew it would go up when occupied. We knew that replacing two HVAC units (out of our three) would greatly reduce consumption. A pure EV would increase it. New pool pumps would reduce it. Guests would increase it. The new mini split in the garage will increase it.
Our usage in April was 2728 kWH. In May, 3799. That’s the result of us moving in and charging the Plug in hybrid as well as warmer weather.
Hard to tell where we will land - so, we chose to maximize the size of the array at 23.8 kW. We can’t fit any more than that without it being visible from the street.
It may cover 100% of our usage. It may not.
But I don’t see our electric use going down much in the future and I certainly don’t see rates going down.
Further, we wanted to establish net metering now. If we’re aren’t grandfathered in the future, we will consider battery storage and time of use rates to see what makes sense.
In retrospect you made the right decision going for the maximum array size. The engineering half of my brain lost the argument to the MBA side and now I am going to pay for that mistake. The one side knows how to build in safety margins while the other knows how to minimize costs and maximize ROI. I should have forced those two guys to sit down and have a serious coversation.
I'm having a NEMA 14-50 recepticle installed in the Petaluma house garage during the big upgrade. I will leave a Mobile Connector plugged in.
Per @Astro14 smart post, if you are considering a solar project, go big or go home. When I was researching and getting bids, they asked for 3 years of usage to gauge the output requirements. I asked them to bump up the number because I knew I would be retiring in a few years and may even get an EV. As a fiscal conservative cheapskate, I didn't want to spend all that money. But it worked out OK, and then some. A few more panels mighta been nice... Who knew?
On a side note, Astro (and most others) did not want the solar panels visible from the street. I, on the other hand, wanted the panels to show because I spent so much $$. Like buying a drop dead gorgeous Porsche and hiding it? The dang installers put them all on the back. Sheesh.
Per @Astro14 smart post, if you are considering a solar project, go big or go home. When I was researching and getting bids, they asked for 3 years of usage to gauge the output requirements. I asked them to bump up the number because I knew I would be retiring in a few years and may even get an EV. As a fiscal conservative cheapskate, I didn't want to spend all that money. But it worked out OK, and then some. A few more panels mighta been nice... Who knew?
On a side note, Astro (and most others) did not want the solar panels visible from the street. I, on the other hand, wanted the panels to show because I spent so much $$. Like buying a drop dead gorgeous Porsche and hiding it? The dang installers put them all on the back. Sheesh.
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We share a single level 1 charger (120v, regular wall outlet) between our two EVs. Been like this for years and mostly been OK for us.
Most annoying part is the Tesla locks the charger to the vehicle so I need to unlock it in the app if my ex wants to use the charger and it’s currently in my car. The Equinox it’s simple… I can just unplug it as needed.
Most annoying part is the Tesla locks the charger to the vehicle so I need to unlock it in the app if my ex wants to use the charger and it’s currently in my car. The Equinox it’s simple… I can just unplug it as needed.
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The charging speed on AC is limited by the onboard charger that performs AC -> DC conversion, not the battery itself. As you stated, the batteries can handle much higher speeds, but the AC charger has to convert household AC power to higher voltage DC power. The fastest AC charging vehicles handle ~19.2 kW, but many people don't have a panel with adequate capacity for that. It's also frequently overkill, because most vehicles are recharged overnight while the owner is sleeping, and the owners aren't charging from 0% to 80% because they don't use the full range each day unless returning from a trip. The only scenario is which is really makes sense is commercial use of a vehicle, where it's for a trade or other business that requires the full range. For example, The Silverado/Sierra EV have 200 kWh packs that take 10 hours to replenish on an 80 amp circuit. But they also have 400+ miles of range, so an owner could use half the pack (~200 miles) and still be able to recoup 100 kWh overnight using just a 48 amp circuit.
It's probably cheaper to add battery storage to capture the cheaper TOU and shift consumption to off-peak hours. I can add another 30 kWh for around $3,000. That's much less expensive than labor to add more racking and panels to my system. I got a quote for $10,000 to add 30 kW of solar. It would have been $3,000 less with the credit, but still cheaper to add storage.