I mentioned in another thread, this would likely be about what you would need for a minimal charging setup, you ought to be able to charge at 240/16A if it's sunny. Should be a fun project. Dunno where you live, but I'd be curious how this works out. You might look into an openEVSE charger, it has an API to allow dynamic rate changes based on output, you might need to futz around with software. I'd probably wire it to an RV hookup box anyway, I use an outdoor 70A GE box with two breakers, for a 6-15 and a standard 5-20 duplex outlet, why not give yourself a little flexibility? It was < $100. Depends on how close everything is, but you never know when a regular plug might be handy, say for a shop vac to vacuum the car or a buffer or a shop light, or ...
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To your point, you absolutely don't NEED any kind of a panel, but I think it kind of depends on how you are wiring things up. For example if you set up with something a little larger than the pedestal above you could just mount the inverter, the two batteries, throw up a wallbox with a 6-15, and run some conduit or something out to the panels, mount an EVSE, plug it in. In my experience, every time I do something that short-sighted I generally wish I'd gone ahead and been a little more pro-active. I mean you *know* this will never run anything but a single EVSE? That white wire sticking out of the box in my picture above is a piece of cat-6 waiting for a biscuit jack
. My sister and her husband come to visit from time-to-time in their camper, they can plug in there. I have a much larger system, but it would be annoying to have to walk all the way over to my main breaker panel, it if I wanted to cut the power right there for a minute.
Yes
Thanks. I think i will but one in my garage just so I can turn on and off if I need to. The inverter is in the basement. And I used the Tesla mobile charger to charge model y. I can adjust the charge amp in the Tesla app. Do I still need a EVSE?The Problem with EV charging is you'll pull more amps than the inverter will provide and it will trip. You probably ain't going to trip any 50A breakers no matter what you do with a 6KW inverter... Something simple like the box below. (Yea, I threw the mess together with a pallet, and some scrap wood, it still needs paint). I'm hooked to my secondary panel, with 24KW of inverter behind it, and I put this pedestal on a transfer switch, so it will feed it from the grid if the solar gives out. I overkilled and ran #4 wire out to the pedestal, but de-rated the breaker to 50A back at the solar/grid panel. The transfer switch means I don't have to play musical plugs/multiple EVSE if my solar goes to poopey. As a geek, I wrote software that monitors my battery SOC and I tell the EVSE to ramp up/down output based on it, but my solar is not dedicated. For a pure solar charge scenario, you only need enough battery to smooth your input to prevent a shutdown from overcast sky. I think basing your output on SOC still makes the best sense, just jack down output when your SOC drops, turn it all off when the batteries hit 10% or something. The API for evse has several options.
OpenEVSE WiFi API | OpenEVSE WiFi v4
The API for the OpenEVSE WiFi module Powered by Stoplight.openevse.stoplight.io
If time is not an issue and you have an adjustable charger, you could just set the inverter to turn on at say 50%, off at 10% and find a sweet spot 10-20A so it kicks on when the sun comes up, then maintains parity with your average solar output, kicking off after depleting the battery.
Have FUN!
As long as it doesn't ramp up over what you can put out it's not a problem. I don't have a Tesla, nor do I know anything about their "mobile chargers (EVSE's)", but if you want a 14-50 I'm assuming it's 240v, and I thought the Tesla stuff was all 40A (9600W) on a 50A circuit. I know I can force down my charge rate from my car, so whatever is the easiest. If you can, it's probably a good idea to program your EVSE not to allow more than the circuit will provide.
Solar->ev is modestly more efficient than solar->battery->ev, and battery is expensive. You have to have some battery buffer and the less battery you have the more you have to overbuild your PV arrays, which leads to PV waste. The more battery you have the more you can store excess PV from a smaller array, but it's more expensive and less efficient. Batteries are simpler to install than PV. Now that battery prices seem to be falling, this could bode well. Around here in the summer your 5K of PV could get you 25-30KWH/day. If you had a 30KWH pack you could see-saw 25 or so over to your car every day when you are unable to plug, that's ~125 miles. With the 10KWH your planning, you have a nice fat buffer to play with, you can flip on the charger and tap it for 40 miles of power any time you are not able to plug in on a sunny day.
