Charging an EV with Solar

[Jonathan on Google Hippisley]

I mostly charge my EV using solar panels on a private circuit. The max power of the panels is 5kW, and it delivers 15-25kWh a day. My house battery is on the same circuit and that is my first priority. It can store 16kWh. In the depths of winter (4 weeks either side of the winter solstice) my off-grid panels struggle to fill the house battery, so there is nothing left over for the car; I’ll write another post on how I charge the car during these bleak months.

 From the end of July to the end of the following May, there is a surplus, the more so because during the in-between seasons (Spring and Autumn) we don’t use any heating or air-con, so we only use about 10kWh overnight.

 The car (Tesla Model 3 basic) averages 6 km per kWh. So 5kWh gives me 30 km “for the tank”, 10 kWh gives 60 km and 15 kWh gives 90km. On local trips around town we use less than 30km a day. A shopping trip to Northam takes 200km and a round trip to Perth up to 350km. But we do these trips less than once a week, so for most of the year the solar panels provide more energy than we need.