Slowest possible AC/DC charging?

Aenergy

New Member
I'm looking into making an off-grid EV solar charger so I'm wondering:
What is the slowest possible AC or DC charging possible? Is it possible to charge at 100w for example?

More specific: What is the lowest wattage (or amps*voltage) that can be communicated to be available from an EV charger to an EV through existing communication protocols used by type 1/2 or CCS charging?

I know around 700w is possible with my charger + lowering charging current in my car (doesn't say amps but I assume 230v*3a) but can it go lower than that? Or is it only possible by the car to limit further?

Why I ask: Slower is better because it increases the area under the curve by allowing charging earlier as sun ramps up/using less solar panels.
 
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I'm looking into making an off-grid EV solar charger so I'm wondering:
What is the slowest possible AC or DC charging possible? Is it possible to charge at 100w for example?

More specific: What is the lowest wattage (or amps*voltage) that can be communicated to be available from an EV charger to an EV through existing communication protocols used by type 1/2 or CCS charging?

I know around 700w is possible with my charger + lowering charging current in my car (doesn't say amps but I assume 230v*3a) but can it go lower than that? Or is it only possible by the car to limit further?

Why I ask: Slower is better because it increases the area under the curve by allowing charging earlier as sun ramps up/using less solar panels.
There are more knowledgable people in the General forum (not many people follow the Energy forum). Perhaps you should ask your question there.

I googled "minimum J1772 amperage" and got this info:

The standardised communication protocol between the EV and charging station (IEC 61851-1) defined a minimum charging current of 6 A before an EV is allowed to start charging. This means that there is a minimum required power before your vehicle can start charging.
 
well most EV on board chargers use about 200 watts at 240 volts just for the conversion from AC to DC volts.
so that's at 240 volt input 1.2 amps used just no battery charge at all.
depending on the EV battery volts, say 360 volts dc if you want to charge on DC straight from your panels then you need to be above this voltage for charge to happen, so you need at least at least 10 x 36 volt panels for this to work as the DC side of a charger usually only steps DC volts down. unless you have a EV with a 800 volt battery pack when the onboard charger can step up the voltage.
so the best thing is perhaps to go the AC power way althought you still need a lot of panels to make it work well.
around 2,000 watts or 8 amps at 240 volts or again 10= panels at 36 volts
charging is always at a wattage and voltage together, so 100 watts at 240 volts is only an amperage of 1 amp or maybe 0.3 kmph charge rate, no good for charging.
so perhaps look at it the other way round, how many KMP Day do you want to add to your range
say 200km per day for a slow but top-up charge
for this at an average 6km per kw you need to add around 40 kwhr of energy with charger losses
so to get this you need a 5kw 240 volt solar converter with around 6,600 watts of solar panels attached.
 
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