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Yes, it’s EV Day here at TTAC. Well, morning. And despite last night’s harangue, one of our Best and Brightest is ready to rock and roll in plug-in paradise. He’s seen the promised land. And he wants to know how to get there with you. Electricians of the world unite! Your time is at hand! Etc..
I have a question for the B&B. While remodeling my home I installed a dedicated line (10/3 wire) to a 30A exterior outlet box on the outside of my house by my driveway. What breaker size and plug type should I install? I’m trying to future proof my home for the day we’re all driving some sort of PHEV. At the very least I’ll be able to use a welder or install a dryer in my driveway.
22 Comments on “Ask the Best and Brightest: How Do I Make My Home EV Ready?...”
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I would install a 40 amp breaker, and locate the panel as close as possible to the Y2K fallout shelter.
All the Prius PHEV kits use the typical 5-15 outlet you will find all over your house. Use a GFCI and a weatherproof receptacle and you’re ready to go. Breakers are sized according to the NEC code so you should check with the rules in your area.
You won’t need a 220V outlet unless you get a full EV, in which case you’ll have a charging station like this and not a typical plug:
http://www.clippercreek.net/
If you want to get ready for an EV or PHEV, you need to talk to your utility company. They will tell you about their EV/PHEV programs and they can give you good advice on what type of electrical line to prep (ex. 220v, 24A).
Many utility companies are looking at using a different (cheaper) electricity rate for an EV. Some utilities are installing a second electric meter or upgrading to a smart meter, to measure EV charging.
If you want the specifics, the SAE has finally standardized a plug; look for your charger to be SAE-J1772 rated.
IMO, you should be preparing for a 220v line, as 110v is too slow to be practical.
As an active amateur electrician, I would say that you should (generally) never put a higher amp breaker than the rating of the outlet (30amp). And 10-3 wire is rated (conservatively) for 30 amps. The earlier comment about using a 40 amp breaker would be a code violation. Plug type: get a 30amp 220v receptacle, which will be like a dryer uses. That might be overkill. You can put in a lower rated outlet, but than you need to put in a matching lower rated breaker.
Your 220v 30amp outlet is going to give you a very substantial amount of current, and will allow you to be highly “EV ready”.
Huh. Never thought about this. I guess I’m semi-future proofed since last year I had two new 220 lines installed in my garage for welders/compressors/bandsaws. 30 amp breakers.
Can you leave the wire in the breaker box and just go without installing the breaker for now? I’d hold off if it’s a name brand breaker box.
I prefer to stockpile W123 & W124 TurboDiesels and vegetable oil.
–chuck
Considering there are a zillion variable about what type of plug, wire, breaker, box, etc, what I would do is run the conduit from my breaker box to a junction box in the garage, and then just make sure you have a pull line running through it.
There, that’s it.
Then when you know what type of plug/amperage/voltage you need, you have the run ready to go, and the electrician can set it up quickly.
Anything else is probably a waste of money as you really have no idea what your future, as yet to be built, or even designed, EV will require.
Considering there are a zillion variable about what type of plug, wire, breaker, box, etc, what I would do is run the conduit from my breaker box to a junction box in the garage, and then just make sure you have a pull line running through it.
I agree completely. You simply don’t know what will be required. Chances are that different electric vehicles will have significantly different requirements for charging stations.
240V*30A*0.8 = 5760watts
One HP equals 746watts
5760 divided by 746= 7.7 hp
Now figure out how fast you can charge.
It takes a large amount of electricity to charge at any sort of fast rate. Remember you only get out what you put in and there is no magic.
Once upon a time, I had a Master Electricin’s License….then the oil embargo of the 70’s hit, mechanical contracting got difficult and I got into computers.
Whatya shoulda done was to lay in the stranded aluminum for a 60 or 100 amp subfeed and a little subpanel. Aluminum is enou8gh cheaper than copper that it wouldn’t have been that much more expensive for the bigger wire.
But as someone who has often done the thing of preparing for some vaguely envisioned need, it rarely works out: the outlet’s in the wrong place, the switch is in the wrong place, the light’s in the wrong place. Murphy makes a fool out of you, time after time.
Install solar panels, or start to love coal or nuclear power. OTOH, no one at Starbucks will know you don’t have solar panels, so you could just keep selling the attitude that you care without really doing that much for the planet.
Enjoy your latte.
I’ve driven a home built EV for two years and upgraded the entire service panel because it was old and in need. I have a dedicated 120 volt 20amp outlet for a 120volt charger, and we pulled very heavy gage wires for a 240 volt 50amp outlet.
I would always recommend as much amperage as possible. The 120 volt charger is slow. The new microprocessor 240 volt chargers(Manzanita Micro) will pull a ton of current and get you back on the road within a couple hours. These chargers will operate on any voltage from 60 volts to 240 volts AC at either 50 or 60 Hz. Current is limited to ~20 amps input or output for the PFC20, ~30 amps input or output for the PFC30 and ~50 amps input or output for the PFC50. There are no switches to adjust to change the input voltage. The charger automatically uses whatever voltage is provided.
The key thing to remember is the car is out of use when charging. It’s nice to drive when you want, and that has a lot to do with how long the car just sitting there charging. I also like having a couple outlets that I can plug a high draw item like a large TIG welder or heavy duty air compressor.
This is very helpful, thanks. The first use will likely be welding as a PHEV won’t be in my budget for a while but… gas crises don’t really announce themselves in advance.
Landcrusher… I do love coal and nuclear power. I’m not doing this for green credentials. I’m doing it to save money if I ever buy a PHEV (possibly b/c ICEs are legislated into extinction) or so my house, when I do decide to sell it, will appeal to rich snobs with either legit or phony green credentials. BTW, no coffee for me, I drink Diet Coke for my caffeine fix.
With 10 gauge wire the maximum size breaker is 30amps. For an outdoor outlet a “ground fault current interrupter” (GFCI) type breaker is much safer and required in many (all?) locales.
Did you see that the new Tesla sedan offers the option of 480 volt charging?
http://www.pddnet.com/Scripts/ShowPR.asp?RID=26553&CommonCount=0
The don’t say how many amps or phases but recharge time is “only” 45 minutes at 480 volts.
celebrity208: what kind of welder will you be using?
I don’t own a welder yet but ideally something along these lines:
http://www.hobartwelders.com/products/wirefeed/ironman210/
Assuming you have room in your main service panel this is a 1/2 day or less project for any electrician worth his salt.
Unless your house predates the Carter Administration you likely have a big enough service panel with extra room for another 220 30A breaker.
I think the Tesla home charger is a 70amp circuit
You might want to ask Calacanis what he bought.
RNader : I’ve driven a home built EV for two years
Can you tell me more about your diy EV? I’ve been looking into it myself, namely at some of the Geo Metro conversions.
victell at g mail dot com
Did you see that the new Tesla sedan offers the option of 480 volt charging?…
Too bad that 277/480 is not available in residential service…
You guys are really scaring me with all this EV stuff. If I have more Better Place nightmares, I’m going to blame it on you.