EV charging for Condos

Suppose you live in a condo, and you got an EV or are considering getting one. I love charging my EV at home, and you should too. What are the options for charging? We discuss the simple (just use a wall plug), to the slightly more involved, to the silly expensive. The most sensible solution I feel is a Level 2 charging station that will charge your EV overnight. From a lifestyle perspective, overnight L2 charging is both convenient, relatively easy to install and (assuming you are on a time-of-use electricity tariff), cheap.

How much charging does an EV require? Thankfully we explored this in a previous post. Each Ontario car on the average does about 16 000 km per year, with an averaged efficiency of 5 km/kWh, we need about 62 kWh per week for our average EV. The table below outlines the various charging options, we have. Starting with the humble plug (1.5 kW L1), through the L2 charging station (7.2 kW L2), to a fast charger L3, along with typical costs for adding an outlet.

Charging Situation	Power	Approximate weekly charging time [hrs]	Cost
Dedicated outlet, 120V, 13 A	1.5 kW	42 hrs	< 500$
L2 charging station, 240V, 32 A	7.2 kW	9 hrs	2-10 000 $
DC Fast charger, 400V, 120 A	50 kW	1 hr 15 min	> 50 000 $

As we can see, while L1 might be simplest, at 42 hours, that’s almost 8 hours every weekday, its something that can work for say primarily a commuter car, particularly if there is public charging nearby that you could use for the occasional Thursday night top-up, before a long weekend road trip. And best of all, its cheap, amazon has a long list of L1 charging stations, you need to be careful to set the charging current to no more than 80% of the circuit load, usually this means 12 A, for a 15A circuit. But chances are there is an outlet in that parking garage that you could use (source, and source).

Its hard to beat the convenience of L2 overnight charging, that is what I have in my garage, while it did cost me a 3 000 $ all-in, its well worth it as I know my car will be fully charged in the morning. Costs vary, the station itself can be had for 1 000 -5 000, with perhaps another 1 000-5 000 for installation costs (source and source). Much depends the site specifics, if the electrical panel is close by the planed charger location that’s cheaper. Also is it a simple charger, or a network charger that can collect usage fees? In a large condo building, this might make a lot of sense, as EV owners who benefit from the charger, contribute to its upkeep and maintenance. Further you get a wealth of statistics that you can use to sensibly plan extensions to the chargers as EV adoption grows.

What about L3 DC Fast charging? For a quick stop on a road trip, fantastic. For a condo, costly, difficult to install, plug-wars, and liable to abuse. Lets tackle these in turn. Start with the cost. Several web-sources put L3 charging station (incl. Installation) at perhaps 50 000$ to 200 000$ (source, and source), that’s perhaps 10 times what a L2 charging station would cost, a staggering cost difference given that charging 10 times the EVs is probably better.

Installation of a L3 station is also challenging. Suppose a condo has 50 units and the average condo has a say 10 kW panel (that would be “50A service”, a little skimpy but probably sensible on the average). Then the building would have a 50 x 10 kW = 500 kW panel. Our 50 kW charging station would add up to about 10% of the total panel, and thus might need additional electrical service. For larger Condos of 200 or more units, this does drop to 2-3 % a much more manageable load.

At the time of this writing, around Toronto, Ontario, we have three types of fast charging plugs: Chademo, CCS, and Tesla. The only commercially available adapters take either CCS or Chademo and convert to Tesla (source). Thus should a Condo board decide to install a L3 charging station, its likely that not all EV owners would be able to use it, as their EV happens to have the wrong plug.

Lastly abuse. Chances are, even if a condo manages to install a L3 charging station, it would still take over an hour to fully charge an EV. This makes it really tempting to leave the car overnight in the “charger”, or at least for a few hours, making it impossible for other drivers to use the charger. While idle fee’s and other incentives might help here. Its an added challenge to manage.

Taken together, a L2 charging station for overnight once-a-week charging is a convenient and relatively inexpensive option for Condo’s. Networked charging stations can provide both usage fees to offset costs, management and statistics to plan future expansion as EV adoption grows. Plus, for L2, all EV’s can use the same J1772 plug, with included adapters.