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by hefferbub 1272 days ago
I live in a multi-unit residential coop community, and we have managed to install a 240v outlet in each of our 90 carports, and are adding more outlets in open parking areas by mounting them on simple fence-like structures. We use 240v chargers that plug in rather than being hardwired so that we can easily move them around.

We have found that a 100 AMP service can effectively serve up to about 20 EVs, so long as the chargers can communicate among themselves to manage peaks. We use all EnelX Juicebox 40A networked chargers and they have that capability.

So how can you charge so many cars effectively with a small service? It is based on load factors.

The average commute length in the US is around 15 miles one way. So most nights for most cars they only need to replenish 30 miles worth of charge overnight. So there are plenty of hours and plenty of amps to cover that.

Of course, some folks come home from a long trip and need a full 300 mile charge, while some didn’t even drive that day and need no charge—basically it all comes out in the wash.

There are other considerations, but the takeaway is that you CAN support a lot of EVs charging for modest investments if you do it smart.

I wrote a white paper on this in case anyone is hoping to do this where you live: https://localforce.io/misc/Cost_Effective_EV_Charging_for_Mu...