I've dug around a little and can't find anyone other discussion of this, wanting to know if anyone has looked into charging the model S from excess solar PV? What I had in mind was a system that could recognise when the PV system was producing more power than was being used by the home and then tip any excess into the Tesla. Cloudy days would get very little charge, sunny days lots of charge. Systems like Solar-Log (Homepage) or the SMA Sunny Home Manager look like they could do the routing. Can the HPWC be given varying amounts of current to work with? My memory was that Tesla recommend leaving the car plugged into the charge whenever possible (even if charging is onlye scheduled to occur at night). I assume this avoids wasting finite battery charging cycles from idle power consumption, cooling etc. If in the above setup an actuator was being used to kill power to the HPWC I assume this is not so good for the car? Has any tried to work through any of these issues?