Equiping a NEW house for EV's

[HoustonFlier]

What should you tell a builder to install in a new-build house in preparation for an EV?

I read this post:

http://www.mynissanleaf.com/viewtopic.php?f=26&t=9631" onclick="window.open(this.href);return false;

Have a separate 240V 20A circuit ran. The socket should match the EVSE you will be using. I started out with a Levitron EVSE that required a S6-20R so thats what i used. The ingeneer mod uses a twist lock connector so if that is your plan then install a matching connector. Number 12 wire would be adequate.

I changed to a 30A Open EVSE hard wired using number 8 wire and a 40A breaker. Since I lease I will have something that will use the extra power in my next car. I do not think I could go back to an gas car.

So the socket depends largely on the charger one uses?

Suggests have box and unterminated wire in box ready for whatever charger you add.

Is there any additional requirements? Certification?

What about best location?
Next to port door so charge cable can reach any car outside of building,
or well inside, perhaps middle of back wall, so it can reach either bay to easily reach EV in any bay?

 

[garsh]

Let the electrician help you.

For now, you need a 20 amp line to the garage. In the future, you may want two (or more) lines (for two EVs), or maybe a future EV charger will support higher line currents (40 amp?). See what the electrician suggests as far as making sure you can easily upgrade/update in the future.

Some EVSEs will plug into an outlet. Others are supposed to be direct-wired. So you may have to wait on installing a receptacle until you've determined what kind of EVSE you will be purchasing.

 

[asinclair]

If you are using the Nissan Aerovironment EVSE, you will need a 40-amp 240 circuit. Installing this will also allow you to use the charger for future cars with 6.6 kw on-board charging. Essentially, the circuit you need depends on what EVSE you are going to use, each one should list the proper specs for installation.

I am not an electrician, so I would definitely get some advice from a professional before taking my advice - All I know is what I had installed in my garage for my EVSE.

Good luck!

 

[ebill3]

Is there a Tesla in your future? If so, have a 240 volt, 90 Amp circuit installed in the garage so you use the Tesla High Power Wall Connector. Even if no Tesla, the availability of high current will bode well for future EVs.

 

[foobert]

If it were me, I'd add +100 amps to the service feed from the utility company (above what you'd normally put in for a house of your size). This will naturally increase the main panel amperage as well.

It will cost you some money for the wiring + panel and possibly from your utility company. But, if this is your "forever home", then you'll be ready for 20+KW charging systems (the Tesla S is already there). Look at thew new RAV4 EV: it has a 10KW charger. Our silly

Unless your main panel is a long way from the garage, the wiring from the panel to the garage is the least of your worries.

 

[davewill]

Receptacles can always be changed. The important thing is to get the wire in the walls. You need to decide how "ready" you want to be. My personal opinion is that even for a Tesla, 30a charging is adequate for home use. With that you can get in 150 miles worth of range in a 12-13hr. charging cycle overnight. For a LEAF, you will have maxed out even the new 6.6kW charger available for 2013. It will also max out all of the current crop of EVs except for the Tesla.

If you feel that's not sufficiently "future proof", you might want to follow in this guy's (link below) footsteps. He did his install in new construction. He put in a RV style subpanel that gives him maximum flexibility for future EV charging. He's forum member, and very friendly.

http://www.casteyanqui.com/ev/evse/index.html" onclick="window.open(this.href);return false;

 

[LTLFTcomposite]

Combine the advice from foobert and davewill.

1) Make sure there is spare capacity in the main service to the house and the service panel. This is a lot more expensive to upgrade than it is to just make larger in the first place.

2) If the service panel is not in the garage, make sure you get what you want in the walls in place now. You might consider just getting a nice fat conduit (2") in place from the service panel to the garage, then you can pull whatever wires you feel like later.

 

[padamson1]

Combine the advice from foobert and davewill.

1) Make sure there is spare capacity in the main service to the house and the service panel. This is a lot more expensive to upgrade than it is to just make larger in the first place.

2) If the service panel is not in the garage, make sure you get what you want in the walls in place now. You might consider just getting a nice fat conduit (2") in place from the service panel to the garage, then you can pull whatever wires you feel like later.

While this is the bare minimum, running the thick wires you want for the amperage an EV (or two) needs is expensive when the walls are up. Have the wires run now, its only a hundred bucks. Also:

3. It's also nice to be able to measure how much energy you're using or be able to put a smart meter on for separate billing. I'm not sure what the latter entails, but the electrician can easily put a second junction box on the run (in series) for a meter. These guys have several rebuilt cheap dial models http://www.hialeahmeter.com/index.php/products/remanufactured-meters/single-phase-watt-hour-meters/ or high end digitals http://www.hialeahmeter.com/index.php/products/ge-meters/single-phase-watt-hour-meters/

4. If you plan to have more than one EV then I think a sub-panel is in order. My guess is that this is enough for a separate billing meter, but you have to check with your utility.

5. (non-EV related) If you're in an area with lightning or sketchy power I highly recommend a whole house surge protector. I have one of these http://www.sears.com/shc/s/p_10153_...i&srccode=cii_184425893&cpncode=30-70471302-2 in each panel. It takes up two breaker slots (one for each phase), but it's not adding to the load, so half-height breakers can be used to get the capacity back and its worth the investment to save appliances (you still want strips on computers just in case, but microwaves, washers, etc won't fry with the whole house).

 

[ljwobker]

The important suggestions here are:

1) run conduit in the walls when building the house. This goes NOT ONLY for the EVSE/garage/vehicle problem, but also for audio/video/networking/whatever inside the house. If you have conduit everywhere, it's extremely easy and cheap to pull more wire, fiber, whatever in the future. It costs a little more now, but it's well worth it.

2) anywhere you think there's a tiny chance you might have a high power device, run higher capacity power cables (see #1, same idea). Once you run the wire, you are forever limited in the amount of current you can carry on that wire. You can always connect a LOWER power circuit using that wire, but never a HIGHER power one. http://en.wikipedia.org/wiki/American_wire_gauge

Running 14 gauge wire on day one is a tiny bit cheaper. Tearing apart your walls to replace it with 8AWG or 10AWG wire later is very very expensive.

I'd suggest you find a local competent electrician and ask them for recommendations also... most of these concepts are pretty simple but it helps to have someone around who knows all the lingo and what/why you're trying to do what you're doing.

 

[smkettner]

What vehicle? Where will it park? Put the 50a electric right there by the charge port. I would have him leave a 3'+ loop in the wall to allow slack for final positioning if desired.

 

[HoustonFlier]

What vehicle? Where will it park? Put the 50a electric right there by the charge port. I would have him leave a 3'+ loop in the wall to allow slack for final positioning if desired.

More future proof then getting. Friend is getting house built, and agree to my suggestion to wire for EV. (Doing solar too)

Recap:

• Run conduit and space for breaker and socket.
  
• Wire for 240v, 50Amp wire minimum through conduit.
  
• Know what the house line is capable of, and increase capacity if needed.
  
• A separate breaker box (sub panel?) or RV style is advisable.

 

[Rauv]

These are all good points. One more: I would recommend using copper wiring, not aluminum. The duty cycling that the receptacles and circuit breaker will experience throughout its life (charging every day) will loosen the aluminum connections and cause significant heating effects at the teminations. Yes, you can use No-Ox compound, but why risk it for such a demanding and critical circuit? Copper is better suited for this application in my opinion.

 

[Nubo]

These are all good points. One more: I would recommend using copper wiring, not aluminum. The duty cycling that the receptacles and circuit breaker will experience throughout its life (charging every day) will loosen the aluminum connections and cause significant heating effects at the teminations. Yes, you can use No-Ox compound, but why risk it for such a demanding and critical circuit? Copper is better suited for this application in my opinion.

In the same vein, a heavier gauge wire than technically allowable, will pay for itself over time due to lower resistance, in addition to the margin of safety. Especially for something that will be regularly carrying high load for hours at a time.

 

[JimSouCal]

These are all good points. One more: I would recommend using copper wiring, not aluminum. The duty cycling that the receptacles and circuit breaker will experience throughout its life (charging every day) will loosen the aluminum connections and cause significant heating effects at the teminations. Yes, you can use No-Ox compound, but why risk it for such a demanding and critical circuit? Copper is better suited for this application in my opinion.

In the same vein, a heavier gauge wire than technically allowable, will pay for itself over time due to lower resistance, in addition to the margin of safety. Especially for something that will be regularly carrying high load for hours at a time.

I didn't know that aluminum was still even used in household wiring? Is it?

 

[mitch672]

These are all good points. One more: I would recommend using copper wiring, not aluminum. The duty cycling that the receptacles and circuit breaker will experience throughout its life (charging every day) will loosen the aluminum connections and cause significant heating effects at the teminations. Yes, you can use No-Ox compound, but why risk it for such a demanding and critical circuit? Copper is better suited for this application in my opinion.

In the same vein, a heavier gauge wire than technically allowable, will pay for itself over time due to lower resistance, in addition to the margin of safety. Especially for something that will be regularly carrying high load for hours at a time.

I didn't know that aluminum was still even used in household wiring? Is it?

Yes, but its typically only used for service entrance cabling, because of cost, in fact it's difficult (and very costly) to get copper service entrance cable (SEU), its pretty much all aluminum. Electricians are well trained to "goop up" the connections and torque them down.. Off course they still loosen up over time, and occasionally need to be checked.

 

[HoustonFlier]

Off course they still loosen up over time, and occasionally need to be checked.

It's called "Creep".

The more the cable moves, the more it "creeps".

Real horror story.