Specs for a future-proof home EVSE installation?

After Level 1 charging for a year at home, I'm ready to spring for a Level 2 charger.

I'm hoping to get opinions about a reasonably future-proof setup.

It'll be installed outdoors in my driveway, about 120' from my panel.

I'm thinking:
- one 50-amp circuit (should I run two 50-amp lines? would a 100-amp line be overkill?)
- one NEMA 14-50 outlet (I don't see myself having two electric cars anytime soon)
- Clipper Creek HCS-40P EVSE I figure I can upgrade my EVSE when I get a car that can handle more.

Thanks for your opinion.

I recently installed my home EVSE, I went with the minimum of a 40Avcircuit for my 32A hardwired Chargepoint EVSE. While it might not be fully future proof for new vehicles, it will provide me fast enough charging to recharge a normal daily use in about an hour.

I think it really comes down to how far do you drive? I doubt that any future EVs will have minimum amp limits beyond a standard wall outlet. So it'll always be "how fast do you need to charge up?" You could always just run an 80A circuit so that if you need a 2nd charger (or double current standard capacity becomes a standard for homes) you have the infustructure there and are ready to go.

Double check the outdoor rating on the Clipper Creek too, Charpoints plug in EVSEs are rated for interior use only, you might be better off going hard wired over plug.

I think you are right to go with a single 50 amp circuit - that way you could charge as fast as 40 amps. I suspect most of the cost will be running the wire, so if you want, run two wires. Since you have a long distance, I think you are going to need pretty fat wires, which are expensive. I'm not an electrician, but since you are mounting the unit(s) outside, I think you probably should go with hard wired units so you don't need to worry about water intrusion into a plug. I have the Clipper Creek unit you mentioned (mounted in my garage) and I have been very happy with it.

Good luck!

I agree with the decision to install a 50 amp circuit. When I was having my house built in 2012, I had two 14-50 sockets installed in my garage. I didn't have an EV the time, but I figured a plug-in car was an eventuality, especially within the useful life of the house. It turned out I got my first EV in less than 6 months after I moved in. Changing the 14-50 socket to a 6-50 for my Leviton 40 amp EVSE was very easy.

I also agree that for outdoor use, a hardwired installation is better due to the lack of a plug and socket interface that can get wet. Of course, you can use a RV box to keep the socket dry, but it adds a lot of bulk to the installation. Even though you may not install a 14-50 socket, make sure that the wire pull includes the neutral, just so you have that option in the future. Consult an electrician to ensure you have the capacity in your service and that the installation is done properly.

f1geek said:

I suspect most of the cost will be running the wire, so if you want, run two wires.

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This is accurate: I ran about 60' of 8-3 wire in 3/4" conduit for about $120 (materials only, I did the install myself). For a 150' span I'd expect to spend about $200, depending on number of corners you have to navigate.

The OP was talking about a 120 foot run. For that length and a 50 amp circuit, I would really recommend #6 copper wire. For the e-Golf it won't matter because it can only pull 30 amps. However, for a future car like a Tesla that can pull 40 amps, the larger wire (compared to #8 mentioned above) will make a difference in heat loss and voltage drop.

I believe any run over 50 feet on a 50 amp breaker requires 6 ga copper. There may be a run length if long enough, that would require you pull 4 gauge copper. Have your electrician check the building code.

Thanks for all the info.

I suppose my one remaining question is: peering into your crystal ball, what cable would you lay in anticipation of the next 20 or so years of home charging development? Is one 50-amp circuit enough?

I've got a good opportunity right now to do whatever I want while my walls are open.

Assuming you put in the correct wire to support a 50 amp circuit, you could charge at up to 40 amps x 240volts = 9.6 kW. Let's assume 100 kWh batteries are standard in 10 years. That would mean it would take about 11 hours to charge your car with a nearly dead battery. How often are you going to need to do that? Will your wife also need to perform a full charge on her 100 kWh battery car at the same time? If so, then run a second circuit to support 2 simultaneous 40 A draws. You could run a second cable now and never hook it up, too, but have it there just in case (of course, you need to buy the wire and install it). Only you can decide what makes sense.

cctop said:

Thanks for all the info.

I suppose my one remaining question is: peering into your crystal ball, what cable would you lay in anticipation of the next 20 or so years of home charging development? Is one 50-amp circuit enough?

I've got a good opportunity right now to do whatever I want while my walls are open.

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When I built my house 4 years ago, I put in two 50 amp circuits in the garage. I had no idea when I would ever use them, but now that I have two EVs, they're really nice to have. I put them mid-way along the side walls. The left space is perfect for a Tesla, Ford Energi, BMW and Volvo plug-ins, and my RAV4 EV because the charge ports are on the driver's side. The right space is perfect for the e-Golf, 500e, and others that have the charge port on the passenger side. When the e-Golf lease is up and we get the Model 3, I will probably rig something up for the right side space so the cable can go over the car without touching. If I had it to do over, I would probably put the socket closer to the garage door on the right side space. All the cars with passenger side charge ports are at the rear of the car.

I think it cost about $600 extra during construction for those two 14-50 sockets. I also specified a 400 amp panel during construction. That was a tougher sell to the electrician until I added in the solar, 50 amp range, 30 amp dryer and other stuff that's actually not currently in use. I still have extra capacity on that front. Anyway, adding it now would be several thousands of dollars because the main panel is on the other side of the house and there's no good way to get there without cutting into drywall to cross a bedroom and run the wires though the ceiling space between floor joists.

Long story short, one 50 amp circuit per car will be enough for any future EV. The only thing I might do differently is to run a single 100 or 125 amp circuit to a sub-panel in the garage. That way you could do two power sharing EVSEs at 100 amps each. Tesla has this feature now in their High Power Wall Connector. Clipper Creek has started to offer this feature also, but only on one of their lower power models. However, that's a luxury that's not really needed in comparison to two 50 amp home-run circuits.

I put two 14-50s in my garage. Even if my wife and I never get a second EV it's nice to have a second outlet for an RV or whatever else needs 240v. If I had a run as long as yours and I wanted to future proof it, I would put nothing less than two circuits with as much capacity as I could afford. That's based on my assumption that the cost of expanding now is going to be much less than expanding later.

miimura said:

When I built my house 4 years ago, I put in two 50 amp circuits in the garage. I had no idea when I would ever use them, but now that I have two EVs, they're really nice to have. I put them mid-way along the side walls. The left space is perfect for a Tesla, Ford Energi, BMW and Volvo plug-ins, and my RAV4 EV because the charge ports are on the driver's side. The right space is perfect for the e-Golf, 500e, and others that have the charge port on the passenger side. When the e-Golf lease is up and we get the Model 3, I will probably rig something up for the right side space so the cable can go over the car without touching. If I had it to do over, I would probably put the socket closer to the garage door on the right side space. All the cars with passenger side charge ports are at the rear of the car.

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Couldn't you just back in the Model 3?

Jeremy1026 said:

miimura said:

When I built my house 4 years ago, I put in two 50 amp circuits in the garage. I had no idea when I would ever use them, but now that I have two EVs, they're really nice to have. I put them mid-way along the side walls. The left space is perfect for a Tesla, Ford Energi, BMW and Volvo plug-ins, and my RAV4 EV because the charge ports are on the driver's side. The right space is perfect for the e-Golf, 500e, and others that have the charge port on the passenger side. When the e-Golf lease is up and we get the Model 3, I will probably rig something up for the right side space so the cable can go over the car without touching. If I had it to do over, I would probably put the socket closer to the garage door on the right side space. All the cars with passenger side charge ports are at the rear of the car.

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Couldn't you just back in the Model 3?

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I have shelving along that wall, so we park very close on that side, preventing ingress/egress from the doors on that side. With Summon, it could be done that way.

IIRC Clipper Creek EVSE's get their smarts from E Motor Werks.
The JuiceBox Pro can also perform the current sharing. I'm told you can even mix and match brands.

You tell the APP what current your wires can provide and the APP take care of coordinating the two Wi-Fi connected EVSE's to share the current.

I just had my main panel replaced and now have an extremely short run of about 24". I expect to breaker and wire for 60 amps, set the APP for 45Amps and let the two 40amp JuiceBoxes do their thing.

My older JuiceBox needed a refirb in oder to remain compatiblity with the newer one I just purchased. E motor Werks did me a great turn-around and price on the service.

Very happy customer

Barry

I have a 50A line dedicated to my EVSE. I only have a 40A EVSE because my totaled Mercedes B class EV charged at 40A. My eGplf charges at 30A so 10A is ignored. The car's charger requests 30A and it ignores the extra 10A. A 40A circuit (32A max) would charge the eGolf fine. You could also go with a 24A EVSE on a 30A circuit. The car will adjust itself to 24A.

GlennD said:

I have a 50A line dedicated to my EVSE. I only have a 40A EVSE because my totaled Mercedes B class EV charged at 40A. My eGplf charges at 30A so 10A is ignored. The car's charger requests 30A and it ignores the extra 10A. A 40A circuit (32A max) would charge the eGolf fine. You could also go with a 24A EVSE on a 30A circuit. The car will adjust itself to 24A.

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OP said 'future proof'. 30A isn't the future, it's almost the past.

forbin404 said:

GlennD said:

I have a 50A line dedicated to my EVSE. I only have a 40A EVSE because my totaled Mercedes B class EV charged at 40A. My eGplf charges at 30A so 10A is ignored. The car's charger requests 30A and it ignores the extra 10A. A 40A circuit (32A max) would charge the eGolf fine. You could also go with a 24A EVSE on a 30A circuit. The car will adjust itself to 24A.

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OP said 'future proof'. 30A isn't the future, it's almost the past.

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When "future-proofing" an EVSE, it's not about what the car can do but what the owner requires. I consider my 15A Voltec unit to have me thoroughly "future-proofed" because it can add 30+ kWh in a 10-hour overnight charge. My daily needs will never exceed that, so I have no need to charge a car faster. In fact, a larger-battery BEV will have even less of a need for quicker charging since any deficit I acquire during a long day can be made up over a couple of nights. A 60kWh battery would suite me fine using only 1.44kW L1 charging, which only adds 10-12kWh during the same 10-hour charge.

So again, the real question for the OP or anyone else is: what are your anticipated driving needs in the future? How fast would you need to charge an EV to recoup the energy overnight? I'm all for building in margin, too. But let's not go overboard, as that gets unnecessarily expensive.

GetOffYourGas said:

forbin404 said:

GlennD said:

I have a 50A line dedicated to my EVSE. I only have a 40A EVSE because my totaled Mercedes B class EV charged at 40A. My eGplf charges at 30A so 10A is ignored. The car's charger requests 30A and it ignores the extra 10A. A 40A circuit (32A max) would charge the eGolf fine. You could also go with a 24A EVSE on a 30A circuit. The car will adjust itself to 24A.

Click to expand...

OP said 'future proof'. 30A isn't the future, it's almost the past.

Click to expand...

When "future-proofing" an EVSE, it's not about what the car can do but what the owner requires. I consider my 15A Voltec unit to have me thoroughly "future-proofed" because it can add 30+ kWh in a 10-hour overnight charge. My daily needs will never exceed that, so I have no need to charge a car faster. In fact, a larger-battery BEV will have even less of a need for quicker charging since any deficit I acquire during a long day can be made up over a couple of nights. A 60kWh battery would suite me fine using only 1.44kW L1 charging, which only adds 10-12kWh during the same 10-hour charge.

So again, the real question for the OP or anyone else is: what are your anticipated driving needs in the future? How fast would you need to charge an EV to recoup the energy overnight? I'm all for building in margin, too. But let's not go overboard, as that gets unnecessarily expensive.

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You aren't looking to the 'future' but the 'now'. You might be driving short term now, but what happens if your job changes or you get a newer car.

Installation of a power line and plug is 75% labor. The parts are minimal (Might even be 90%). So spending a couple more $$$ to get a 50Amp circuit is 'future' proofing your garage. Spending it now on a 30A and then finding out you needed a 50A (spending the same amount to correct) is not future proofing.

I did not future proof my garage, that's because I didn't have enough room in my circuit panel for 50A circuits. (I would have to upgrade the panel). But if OP is asking for Future Proof, a 50A is probably the best thing to do for minimal cost.

If your existing circuit only allows a 30 amp EVSE, then so be it. But if you have the ability to plan a new circuit to your garage, go with a minimum 50 amp one, even if you don't need it right away. The labor involved is the most expensive part; the additional parts cost for thicker gauge wiring is minimal compared to that.

Another thing to consider: what if you end up with two plug-in cars in the future? Either two BEVs, or one BEV and one PHEV? It would be nice to have the capacity to plug both cars in simultaneously, for convenience but especially to take advantage of off-peak rates, but not if you intentionally hobble yourself.

I ended up running 6ga wire 60 feet. It's connected to a double pole 60A breaker. Clipper creek and TESLA are the only people who make an EVSE that can handle a 60Amp circuit.

Wrestling the 6ga wire was a PITA, especially going inside the electrical panel. I realize this is more than I need, but wanted to put at least this much for now hoping it will allow for future improvements in the on board chargers and battery sizes.