In Smart Charging you don’t directly control the battery. You tell the charging station about the maximum it should supply to the car. Then the car determines for itself how it will charge its battery, as long as this capacity does not exceed the charging station’s maximum. So the car’s Battery Management System retains control.
This question is difficult to answer for a particular car. It depends how big the battery is, how much power it still contains at the moment charging begins, the capacity the charging station can deliver and the maximum charging capacity of the car. However, we can say that the average car drives about 30 km a day. In order to charge for this distance, a 3-phase charging station needs a little over half an hour. Since a car is not in use for an average of 22 hours a day, there’s plenty of time to charge it and so it’s not necessary to charge all cars at the same time.
On average it will indeed take a little longer to fully charge the battery since not everyone can charge at the same time. However, the charging algorithm can be designed so that people who are in more of a hurry can also be charged faster, and that people who will be spending the night at home wait a little longer. After all, it’s no problem for the latter group if charging takes a little longer.
The basic principle of Smart Charging is that no one is ever confronted with an empty battery when he wants to set off. If this should nonetheless happen due to insufficient local capacity in the grid, then the grid administrator is in default and it will need to lay additional cables. Thanks to the measurement devices installed for Smart Charging the grid administrator can recognize this situation in good time and so prevent this occurring by installing additional cables.
That’s correct, it’s not the grid administrator who does this but a commercial party instead. You as a driver have a contract with this commercial party, including agreements about how your car is charged. Generally speaking the more flexible you are as customer, the less money you need to pay. If you always want your car to be charged immediately, you will be able to agree this with the commercial party but it will probably mean that your contract is more expensive.
Nowadays almost all electric cars are able to communicate using the ‘mode 3 protocol’. If cars can communicate with the charging station via this protocol then they can smart charge.
All this fuss and bother with charging – isn’t it better if I just charge my car using a normal socket in the garage?
That’s certainly possible, but even then you can benefit from Smart Charging. If for instance you switch on a kettle, an electric hotplate or oven that is connected to the same circuit, then this can quickly overload the fuse in the fuse box. Smart Charging can ensure that at the moment the kettle is switched on, the car reduces its charging rate a little. On the other hand, if you have solar panels the car could increase its charging rate at the moment that the panels supply a lot of power.