Demand Factor For Electric Car Chargers?

[Jaron6182]

I have a customer that wants to install 31 receptacles for electric car chargers. The Units are not permanent they will have pigtails and charge many different types of electric cars. The first thing I need to figure out is my total load. Is there a demand factor for these charging stations? I plan on installing 31 Nema 14-50 receptacles. But what do I figure for my total connected load? Please advise.

 

[luckylerado]

I have a customer that wants to install 31 receptacles for electric car chargers. The Units are not permanent they will have pigtails and charge many different types of electric cars. The first thing I need to figure out is my total load. Is there a demand factor for these charging stations? I plan on installing 31 Nema 14-50 receptacles. But what do I figure for my total connected load? Please advise.

I do not see a demand factor in 2014. In fact NEC says to consider the load as continuous unless there is a load management system in place.

625.41

 

[iwire]

That's going to be a big feeder.

 

[gadfly56]

I have a customer that wants to install 31 receptacles for electric car chargers. The Units are not permanent they will have pigtails and charge many different types of electric cars. The first thing I need to figure out is my total load. Is there a demand factor for these charging stations? I plan on installing 31 Nema 14-50 receptacles. But what do I figure for my total connected load? Please advise.

See article 625 of the NEC. There is no demand or diversity factor for this kind of installation. If you have a commercial parking structure, especially if it's for a single corporate entity, you would expect that everyone comes in more or less at the same time and your chargers could be running full tilt by 0800. That said, if you happen to be in Oregon you're in luck. Based on their examination of how chargers actually operate, they've come up with a diversity table, see here.

In your case, the answer is 60%.

 

[Rampage_Rick]

NEMA 14-50 says Tesla. None of the other common EVs will draw more than 32A or 7200W. Half are limited to 3300W.

Of course once you put in 14-50s you have to plan for a fleet of Teslas arriving and all of them sucking 40A