[Eric E]

My company will be designing a PHEV charging infrastructure for a high density "green" luxury living community. The concept is to provide one charging port for each vehicle parking space.

My question is: Will we need 50amp 220volt charging for each car, or 30amp 220volt, or will a 20amp 110volt outlet be sufficient? I think most RV parks provide a 110v 50amp service for each space.

Although I will want 220v in my garage for a quicker charge, multiply that times 2000 parking spaces and the whole electrical draw in the community changes.

Also...does anyone know of a potential standard for North American PHEV 220v connectors? (The 110v standard is obvious)

 

[ustwatching]

energy

E.V.s all need electricity. You need to be thinking about having more generator capicity as we move to the E.V. It takes about 17 KWhrs to move one E.V. for 1 hour. That's a lot of electricity to move the fleet of automobiles in the U.S. for 1 hour each day. I just hope we arn't to late getting started. I have been hearing the "in about 10 more years" for the last 50 years.

 

[nlh_90210]

standard means cheap, vetted, and available

I don't know much about electric outlets (other than don't stick a fork in it), but my guess is that going with a standard Voltage/Amperage is probably the best idea. If you are going to support EVs then go with max current. Step-up transformers are much easier to install later than putting in better current capacity. Also, assume that any plug-in car (worth a darn) will be compatible with 110 VAC.

Of course step down transformers are also easy to install so maxing out power may be the best (220VAC x 50Amps = 11kW). I guess it'll come down to the trade study of 220 vs 110, but my guess is that max current is better what ever the voltage.

As an aside, I would expect the average household to at least double it's electric consumption over the next decade as things like distributed generation, distributed storage, and Vehicle/Home to Grid become mature. Making the over all household wiring more robust to high current is better, even if more expensive.

 

[KariK]

Well, I do not know where that 17 kWh figure is from. The Volt will use 8 kWh for 40 miles, which is about an hours drive in city driving.

The nightly recharge is 8kWh max. GM has mentioned that the Volt can use either 220 V or 110 V outlets, and that using 220 V outlets, the Volt could get half recharged in an hour. That would mean a 20 A 220 V outlet would be sufficient. Of course, if a 220 V outlet is inconvenient, then a 110 V 40 A outlet (or the 50 A outlet mentioned above) would also work.

 

[Koz]

KarikK,

I think it might be Eric E's last job if he only designs for the Volt. There are other EV's now and will be many more in the future.

Eric E,

Very interesting question. I'm not an EE, but do have to know a little about electricity and wiring for my day job. I think you should enlist the aid of your local utility for your design. They should be VERY interested in EV charging and may be able to offer significant help. 50A 240V would certainly be nice, but may be cost prohibitive. For 2000 vehicles, you would need a lot of capacity. Perhaps it would be wisest to circuit for a percentage of EV's (say 20%), but not do full install of charging equipment. Run circuits to reach all parking, but leave the charging outlets to be installed by the owner if needed. Unfortunately, it will be a long time before more capacity is needed. This will cost a lot less $ and put a smile on the developer's face, and will also be a reasonable solution for the owners for a long time. 240V or 120V should be a safe enough bet for compatibility. Long runs may dictate 240V is best. Can be 30A circuits instead of 50A.

 

[Eric E]

Excellent comments Koz

Good comments...Thank you.
I received your reply while in a meeting to discuss this very topic. Here is the result of that meeting. Note that much of our direction is a result of your comments.

We are currently considering 220v 30amp for all locations with a max load of <20% at any given time. We agree it will be a long time before even 20% of the parking spaces will be occupied by EVs. (If ever)

Our thoughts are that if the demand becomes >20% we can begin timed load sharing if necessary. The higher current of 220v 30 amps makes this more feasable because the charging times are quicker.

220v 30amp wiring is more cost effective and easier to run and manage, particularly at distances >50 meters.

Surprisingly we've found that even when half (1000) of the spaces are occupied by plug-in vehicles it does NOT affect the overall community load when charging during off-peak hours. (10pm-8am)
Also, peak hours for our community vary significantly from summer to winter and also vary differently from that of our local utility.

We've started using a new phrase: "Electric Vehicle Load Management" EVLM.

It has been noted that approx 65% of our power is Hydro, 9% Nuclear, 20% coal and 6% other.

We have decided to cap the pedestals without connectors so that appropriate connectors can be installed when required. Small labels will be affixed to the pedestals in plain view stating their intent for plug-in EV use.

Personal Note:
The more we look into this the simpler it becomes. I don't believe the current grid will be affected by plug-in cars for decades.

Any further comments would be appreciated...

Cheers!

 

[pennor1]

Who knows what plug configuration GM will choose for the Volt. Actually who cares? The 110v plug will no doubt be the standard North American plug we all know and use every day. The 220v, should they choose to go that way, could be any configuration, from the common RV 50-amp, to the common dryer 30-amp, or even the stove configuration. there are so many standards in 220 to choose from.

But as every RV'er knows, you carry some adapter plugs with you. You learn quickly what you need and you pick them up and carry them wherever you go. So if I were designing a parking slip, I'd run 220 to each post. and install an RV 220 plug AND a 20 amp 110 plug in the same water proof housing. Because no matter what GM comes up with, you can be sure that subsequent vehicles from other manufacturers will have different plugs.

 

[NZDavid]

Charging

I would run with 240V 30A circuit if that is the most cost effective. As you are going to label the circuit as EV charging, you could consider placing a timer in the circuit box to ensure nighttime charging.

I am certain in future years having EV capable parking spaces will raise the value of your units.

 

[Koz]

Glad I could help. That is surprising that 1000 vehicles charging at once at off-peak hours won't affect community peak demand. I guess since they are high end residences each service is 300-400A, so it makes sense if that's the case. I do think many people, especially ones paying for luxury properties will want to charge when it is convenient for them and not be confined to only utility off-peak charging. It shouldn't matter for some time since charging needs will have to grow, but the only times that it would likely be an issue are residential peak which is a little different from the utilities off peak. The time clock could prohibit charging from 7-9AM and 5-7PM or whatever these two periods turn out to be. Another possibility may be intelligent load management. FPL here in South Florida and many others use load shredding devices. If V2G doesn't come about, then existing load shedding tech could be used to safeguard against overloading and people still could charge whenever they want. Still another option would be to allow a limited number of homeowners to pay extra to be able to charge on-peak. I suspect most will not need this so it should work out well.

 

[Red HHR]

Where do I place the outlet?

My garage is almost done, I have the big orange cable and the 30amp two pole circuit breaker. I was going to place the outlet half way down the side wall as the volt was to have two side outlets. Now it has one and they will not tell us where they hide it???

I want to finish my garage, where shall I place the outlet??

Red HHR

 

[Eric E]

Definitely put the charging port in front of the car. That is how it will be in every car lot on the planet even if GM doesn't get it right on the first volt.

 

[Koz]

Get set

Install it on the ceiling and hang a retractable cord where needed as KENGLEN76 suggests http://gm-volt.com/forum/showthread.php?t=301

 

[Eric E]

Install it on the ceiling and hang a retractable cord where needed as KENGLEN76 suggests http://gm-volt.com/forum/showthread.php?t=301

Oh yeah...duh!

 

[hvacman]

rough-in conduit only

A little late on this thread, but here's my 2 cents.

Suggestion - Plastic is cheap. Rough-in conduit and pull strings that could handle conductors up to 50A 240 V 1 phase. This would cover you for charging larger vehicles in the future. Copper is $$$. Don't pull conductors, etc. until the EV market actually develops and you have actual needs. This doesn't help in your panel or service sizing, but its a start.

My instinct is that the market will probably standardize on 20 A circuits for passenger cars and that most on-board vehicle chargers will be dual-voltage with a "fast" charge at 230V and "slow" charge at 115 V, matching the Volt configuration.

The reason why is that 20 A/115 V is a very common standard residential circuit size (and code-required for kitchen outlets) and uses the "standard" receptacle spade configuration that we are familiar with. In a pinch, when visiting aunt Mabel, you could just plug into her kitchen outlet and be able to re-charge without popping a breaker.

115 V circuits larger than 20 A involve odd spade configurations, etc. which would limit charging options away from home.

A good feature that the manufacturers should consider for the chargers would be the ability to select a slower charge rate that would work on 115 V, 15 A circuits. There are a lot of homes that are mostly wired with 15 A circuits. This would add 2 hours to the Volt charging cycle.

 

[Eric E]

Good Points

Thanks for your comments, I keep watching this thread for any new info.

Although I agree that running conduit would be enough, we will be running 110v 15amp to the pedestals anyway for cold weather block heaters. (Kinda necessary in the northern mountains of Montana)
The upgrade to 220v 50amp wire is quite small because most of the cost is labor.

Its possible that this "green living" development might attract some attention, particularily in 2009, and the target group of buyers will likely understand the value of an active charging port for plug-in hybrid cars.

Dollar for dollar the "Plug-In Hybrid Fast Charging Port" might have more of a positive green energy perception than even photovoltaic cells and recycled materials by 2009.

I think we should pull the wire and have the circuit ready with just a flip of the breaker.

 

[Red HHR]

Windmill in

OK, I have the windmill putting power into the garage. The garage abuts the kitchen so I may want to back the car in to unload the groceries. Besides if my wife is to drive the car I will have to back it in as she does not like to back up. With a side mounted plug on either side of the car a center of the wall plug would be ideal. It would not matter which way I park the car. I guess I could put in two plugs as the panel is in the front of the garage. Of course they may have some robotic inductive coil that parks itself under the car to automate the recharging

Red HHR

 

[Mausoldj]

Eric,

If you'd like I could send you an industry background report on PHEV/EV recharging infrastructure companies. It may be more cost efficient to use an existing supplier. I would stay away from AeroVironment and AC Propulsion since both utilize a 480VAC system. The Volt will include a 240 and 120V port on each side, therefore I would opt for the 240V system. If you try doing it yourself you may run into some trouble, since utilities have been strongly opposed to using non-smart recharging technology. I'm trying to put together a company to develop a low-cost Level 2 equipment level that utilizies a Level 2+ charge, so we may be in contact.