nekomatic wrote: Thu Mar 27, 2025 2:49 pm
Wiring regs say that you should have a dedicated circuit for any load that regularly draws high power for an extended period, and of course you need a proper charger if you want to use a smart charging tariff, but aside from that I'm not convinced most people need a 7kW home charger for their electric cars. If you get roughly 3 miles range per kWh of charging then six hours from a normal socket should give you 40+ miles, which I'm sure is further than most people drive their cars most days.
This is a reasonable line of argument. It tends to make me think that it would be useful to have a car which it is really easy to take some/most of the batteries out, and store them for the day when you want to drive more than 60km or whatever. So you aren't driving around much of the time with a huge amount of dead weight, consuming more energy and doing more damage to the road, your tyres and your suspension. Though it is going to require a bit of ingenuity to make it practical to manage batteries perhaps in the quantity of several hundred kg.
Though I think it is not actually very good for batteries to be kept nearly full most of the time. If you are to "smart charge" in the sense of managing your batteries to maximise life, then it becomes more complicated than just topping up the amount you travelled today. Some charging software is capable of taking such issues in to account, though you also have to communicate more with it about your plans.
And then there is the issue that a full battery gives you the option of driving a larger distance, without making time for an expensive fast charge, and without having to predict it some days in advance. We don't have to worry about such issues with liquid fuel.
And then there is the issue of potentially making that battery capacity available to reinforce the electricity network, which could become a valuable service. To make that worthwhile, you need a 2-way charger, which most today aren't, and a decent capacity like 7kW or even 14kW.
So, it's all a bit complicated really. And most people don't want that complication.