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You don’t charge off the mains you charge off the shipping container megapack right behind the charge stalls.

BYD has a 14.5 megawatt hour pack that fits in a standard 20 foot iso box with its power converters at that.

14.5 Mw is 28 500kw charge stalls running flat out from a single 20’ box two of those boxes end to end would be the size of a American 40 foot ISO box which is more common here. So a typical 40’ would support 56 stalls at 500kw remember V3/V4 stalls are 250kw not 500 so double that again in supported stalls numbers.

Each EV to go from 10% to 80% of a 75kWh pack like a Model 3 needs 57kWh accounting for 10 ish percent DC-DC charging losses typical for fast DC rates into that sized pack. Two 20’ BYD 14.5 packs is 29,000kWh you could charge 511 Model 3 sized packs with those megapacks and charge them slowly over night for 8-12 hours.

But but the grid. Go look up at the typical suburban distribution lines in wood poles count the insulator disks each one is rated at 1000-2000volts so you probably have 7200 or 12000 volt triple phase lines top and one on each arm.

The Wal-Mart down the road has 7 lines per pole four on the bottom arm two on the top arm and one across the top all of them have 10 disk HV insulator stacks so that’s 3 phases , 3 phases and a G/N phase for the 7th wire. Those wires are 600 mcm sized aluminum. @12000V typical for T&D in suburban areas the top triple phase is carrying 400 amps per phase @12,000V not exactly triple it’s 2.77 due to the nature of Delta wired 3P AC so 13.296 megawatts the bottom four lines are a Y wired triple phase and in this mode you do get three equal phases of 400 amps relative to the 4th wire ground/neutral. It’s why there is four HV lines not 3. That second set under the first is carrying 14.4 megawatts for a total pole T&D of 27.696 megawatts.

So how much current is needed for an 8 hour overnight refill of said megapack ? Over 8 hours you need 3.6 megawatts extend that to a 12 hour refill and it’s 2.4MW

You are not even stressing that individual small power pole with 3.6MW that’s only 108 amps on the top triple phase. For comparison the Wal-Mart itself is a 1-1.2 megawatt load but it’s not open 24/7 it closes at 2300 and won’t open until 0600. Remember those packs are holding 500+ full charges worth for a sedan sized EV and could support 100+ V3 stalls all at once today with existing Tesla tech.

You have 27 megawatts at the property edge you need 1/10 of that over a 10 hour window or 3.6MW for 8hr buy cheap wind at night we had negative $11 a couple days in a row overnight in ERCOT and it’s almost always $20 or less at night for West Texas wind that’s 2 cents per kWh or less every night mostly all night. You can sell that at 30-50 cents at the fast DC handle rate Tesla owners pay less vs retail users. Sometimes under 30 cents off peak. I charge off my panels above the steel building so it’s zero cents effectively since the panels paid themselves off years ago for those sets. It’s what could I have sold that power for is the opportunity costs.

So yeah you can have 50+ stalls and 500+ full charges worth per day at your typical Wal-Mart parking lot. Even if you only had the top triple phase at 7200V you could fill the megapacks while the Wal-Mart is closed and using much less amps it’s only running it’s freezers and minimal AC until morning right before opening I used to manage a target night stocking crew right after secondary school and before deploying it was always hot because the A.C. Was off at night and dark too with every third light on and two off. So I know for a fact when big boxes are closed they ramp way down the power costs by design.

Forgot this is about 5 min charges...

The V4 Tesla standards can do a 5 min charge of 56kWh to a 75kWh pack which is 10% to 80% plus losses.

5 min which is 300 seconds.
56kWh is 201.6 megajoules now we have common second based units.

201.6/300 = 0.672 MJ/second

672 kilojoules per second is also 672,000 joules per second which conveniently is also watts per second.

So 672kw fills a Model 3 pack 10-80% in five minutes assuming the pack could take a 9C effective rate 56kWh/75kWh*time=9C

The V4 NASC through the existing plug maxed out during testing and certification at 1000 amps and 1000 volts so the plug can already do a solid megawatt it’s the packs that can’t take that rate.

672,000 joules pushed at 800 volts is 840 amps well under the V4 cert limits.

14,500 kw megapacks at 1C discharge rates supports 21 simultaneous V4 stalls at 672kw twin packs in a 40 foot iso box can support 42 stalls and given that LFP calls can do 5 C rates not just 1C you see how this works for a bucee’s sized Tesla complex. You still have 511 Model 3 packs worth of kWh in a 40 foot is box as well. Rate of discharge is higher but overall kWh is the same.

Again normal triple phase 12,000V T&D can fill that 40 foot iso pack in 8 hours cheaply overnight 12,000V is not even high for local T&D we have 32,000V just down the road on concrete mono poles not taller than wooden poles you can tell because they have 20 disk insulator packs vs 10 or 5 for 7200V single phase individual house rural drops.

I am well versed in the power industry I do consulting for a number of industries ERCOT & power is one, oil and gas is another.