250km is at least 40kWh. To get that in 15h maximum sun you need at least 2.7kW of panels. Naturally you don't have 15h of peak output, so 4.5kW of panels sound

250km is at least 40kWh. To get that in 15h maximum sun you need at least 2.7kW of panels. Naturally you don't have 15h of peak output, so 4.5kW of panels sounds about right.