AC Charging Basics
AC charging is all about the car. While the EV charger is called a charger, the actual charger is in the car. Confused? The EV 'charger' is actually more like a smart socket which can talk to the car and some can undertake remote management, load management and control load across multiple chargers. The real 'charger' (which is technically an inverter) takes AC from the socket and turns this into DC to feed the battery. In any charging scenario there are three point of weakness:
The AC socket
The AC inverter on the car
Intelligent chargers will always work to the weakest point. For example a 22kW AC charger charging a Hyundai Kona will only release 7.4kW because that is the limit of the cars AC inverter.
So when you're looking at AC chargers for your fleet, bear these things in mind:
Communications: smart chargers come with a global communications standard (OCPP - 1.6 ideally) built in, as well as a modem/ethernet/WIFI options. These chargers can be managed and controlled remotely and can report on usage etc
Monetisation: if your AC chargers are for fleet behind locked doors then this isn't an issue. If your chargers are for your staff or the public you'll want to install chargers that CAN be monetised, even if you don't turn it on today.
Load management: if you have limited capacity then manage load using smart chargers is a consideration
Fleet growth: you can daisy-chain one communications enabled (modem/ethernet) charger to up to 20 simpler chargers
Installation: while AC chargers are a lot cheaper to purchase and install then DC chargers, distance to the meter board is still a consideration.
Attached cable: we recommended socketed chargers (no cable) because NZ has a mixed fleet of EV's that are Type 1 and Type 2. By installing tethered cables you are limiting use to one type. The European standard for public charging is socketed and most cars come with a cable that suits their car.
We recommend chargers that are intelligent, can communicate, have global standards, and are socketed (no cable attached).