An easier way to charge vehicles at home

[brianl703]

I do know they are installing 400A mains in some new homes just for this reason although sometimes the way that is implemented is through two 200A panels.

It's the most common way 400A service is implemented around here. Two 200A panels are cheaper than one 400A panel and you get double the number of circuit breaker spaces.

I have 400A service with TWO 200A 42-circuit panels and if I just had a single 42 space panel, it would be full.

 

[brianl703]

My understanding is that if you have two columns in your breaker panel, then you have 220 capability.

The REA (Rural Electrification Administration) standard was to have a 240V service feeding a fuse box with a 60A MAIN fuse feeding 4 to 6 screw-in fuses for 15 and 20 amp circuits, and a 50A RANGE fuse for an electric stove. And this standard dates back to at least the 1940s.

If the stove is gas, the RANGE fuse isn't used, so in many cases it was used to feed a subpanel to add air conditioning or additional circuits.

So even back in the 1940s the standard was 240V service.

 

[Number_35]

Not here. 200a didn't start showing up till the 90's. When we redid our house a few years ago we replaced the 40a box with a 200 though.

Agreed on 200 A service - it was relatively rare for a long time.

However, this is about 240 V, which has been around for a long time. Ovens and clothes driers run on 240 V.

Our service here comes in OH off the bug (7200 V:240 V transformer on the pole) as 240 V single-phase. The 240 V is centre-tapped, with the middle being N.

Either end of the winding to N is 120 V. End-to-end is 240 V.

 

[Andrew1972]

The end and short is Level 3 charging has too many barriers and limited use cases beyond excess cost to be practical at home.

It is akin to installing your own gas pump and tank at home.

If you have proper panel Level 2 works wonderfully typically for under $1000 installed.

 

[JHZR2]

So long as it’s post meter on the two mains hard bus in there, why would they?

 

[JHZR2]

Typical 120V outlet is 10A. A pretty simple Watts Law calculation says this circuit can deliver 1200 watts.

Options vary when wiring up a 240V outlet, but 30A and 40A are pretty common. A 240V/30A circuit can deliver 7200 watts. Six times more power than a typical 120V household outlet.

Ummmm, typical residential circuit is 15A, or 20A if fed with 12ga wire.

It’s called “Ohm’s Law”.

 

[JHZR2]

Ok that makes sense, but I think I have some 20 amp 120v outlets in the kitchen so that's 2400 watts right there, no?

Code has been two 20A circuits in kitchens for a while IIRC.

 

[Rmay635703]

Not here. 200a didn't start showing up till the 90's. When we redid our house a few years ago we replaced the 40a box with a 200 though.

I have illegal 40 amp service (circa 1868 home)
and have charged at “20amp” (16.6 in reality) which is the fastest that car could draw on ac and had no issues.

Systems to switch existing circuits between 2 devices for use with existing boxes have been around forever in the case you want to charge your car using unused “capacity “

AKA How often are you running all burners on your electric oven, electric hot water, dryer, washer and HVAC at the same time?

It is rare any home maxes out a 100 amp panel in draw even once as your literally never run everything.

Most EVs can never draw more than 32amps meaning it’s pretty easy to supply that off a 100amp panel

 

[ecotourist]

Most houses are fed by a single-phase transformer, with a center tap on the secondary which is connected to neutral.

And if there are no 3-phase loads, like an in apartment, then they can use a less expensive load center like that normally used with split-phase service. In this case, 2 phases plus a neutral are fed to this type of load center giving you 208V phase-to-phase and 120V phase-to-neutral. (This kind of stinks for EV charging, because most EVs charge slower on 208V than they do on 240V. They could install a boost transformer to increase the 208V to 240V but nobody seems to do that...)

Thanks for your comments Brian703.

When my Tesla is charging at home it typically says it's charging at 230 - 231 Volts and 32 Amps. For most local driving I'm back up to a full (ie 80%) charge in 30 to 120 minutes. There is no need for anything faster for at home charging.

 

[brianl703]

Ummmm, typical residential circuit is 15A, or 20A if fed with 12ga wire.

I've been reading about some NEC proposals to allow 10 amp, 120V circuits for lighting. Who knows if it will be accepted and not sure what the benefit is.

 

[brianl703]

When my Tesla is charging at home it typically says it's charging at 230 - 231 Volts and 32 Amps. For most local driving I'm back up to a full (ie 80%) charge in 30 to 120 minutes. There is no need for anything faster for at home charging.

I would charge my Volt at 8 amps, 120V at work and that added more than enough range to get me home without using the gas engine.

And for most of my driving, the 13 amps, 240V charger is more than enough. I actually charge it at 120V most of them to keep it from heating up my garage as much in the summer.

 

[JHZR2]

I've been reading about some NEC proposals to allow 10 amp, 120V circuits for lighting. Who knows if it will be accepted and not sure what the benefit is.

Maybe. I wanted a 10A breaker for one of my properties because I wanted to limit its utility to others. No place carried them and I had to special order.

For LED lights… or more specifically, to let smaller conductors be used as part of a power distribution for dedicated loads I guess it could make sense. It’s another romex variant to stock…

And won’t help with charging EVs one bit…

 

[George Bynum]

I've been reading about some NEC proposals to allow 10 amp, 120V circuits for lighting. Who knows if it will be accepted and not sure what the benefit is.

From what I've read, it is to allow smaller wire (16AWG copper, 14AWG aluminum) for economy. In my OPINION, it will require new breaker designs to lower trip times on overloaded circuits as the circuit resistance will be higher.

 

[Rmay635703]

I've been reading about some NEC proposals to allow 10 amp, 120V circuits for lighting. Who knows if it will be accepted and not sure what the benefit is.

Cheap aluminum core chicken wire is cheaper than copper.

Remember those ideotic low voltage light circuits with speaker sized control wire?
Welcome to unnecessary lighting circuits 2.0

Due to LED lighting they are trying to save $$$ providing just enough to run them.

Worth noting my very old home has 110v outlets that are dual voltage 110/220 all in an almost standard looking outlet. A single outlet is rated only at 10amps which follows an old British standard for tea kettles

 

[MrHorspwer]

It’s called “Ohm’s Law”.

Watt's Law - P=IV
Ohm's Law - V=IR

Two different things

 

[JHZR2]

Watt's Law - P=IV
Ohm's Law - V=IR

Two different things

I don’t deny the calculation (power factor aside for AC circuits in terms of what can really be done), but it still is typically displayed with the wheel of all relevant calculations and generically called Ohms law, since power can actually be calculated multiple ways.

You are technically correct though in terms of the calculation you provided and the term Watts law.

 

[PandaBear]

Watt's Law - P=IV
Ohm's Law - V=IR

Two different things

I don’t deny the calculation (power factor aside for AC circuits in terms of what can really be done), but it still is typically displayed with the wheel of all relevant calculations and generically called Ohms law, since power can actually be calculated multiple ways.

View attachment 110648

You are technically correct though in terms of the calculation you provided and the term Watts law.

Seriously, 2 grown men fighting over algebra?

 

[JHZR2]

Seriously, 2 grown men fighting over algebra?

Where’s the fight? This whole thread has gone down the path of NEC, wire size, 10A circuits. Discussing nomenclature in common use is far from a fight.

Of course, if we want to really talk about charging EVs we do need to up the volts and amps a decent amount….

 

[Rmay635703]

Or perhaps we accept that home charging covering the range of

110VAC - 40 miles a day at home charging
220VAC - 250 miles (32amp)

Is good enough for 95% of people without any real upgrade and if you have to go further you use the public charging station or you own this instead

I know folks with 2 plug ins that run strictly 110vac to both. Math is even better if you have 110vac at work.

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[PandaBear]

Or perhaps we accept that home charging covering the range of

110VAC - 40 miles a day at home charging
220VAC - 250 miles (32amp)

Is good enough for 95% of people without any real upgrade and if you have to go further you use the public charging station or you own this instead

I know folks with 2 plug ins that run strictly 110vac to both. Math is even better if you have 110vac at work.

Aptera raises $40 million to bring solar electric car with up to 1,000 miles of range to production

Aptera announced that it raised $40 million to bring its solar electric car with up to 1,000 miles of range...

electrek.co

That thing is a cool bike, maybe someone will use it to commute for fun, but not as their only way to commute. There will be eventually more public charging available just like back in the 1910s when automobile started showing up along with gas station. People were probably wondering back then where to get gas when they didn't refine them everywhere like they had pasture for horses.

Currently we have 2-3 hrs of charging at work for cheap or free, I don't expect them to be free but probably low cost eventually, so most people may find out that they can live with a smallish range for a commute car (say 100 miles after 10-15 years for a Corolla, or 100 miles after 20 years for a Tesla) at a low cost in 1 of 2 cars in the house, and a gas car for long trip. They probably will still charge for 40 miles a day at home regardless, and at work top off another 60-150 miles on demand.