I do not understand why my Clarity is charging at a lower rate (in the cold) sometimes. It starts at about 7kW then drops to 4kW. I have noticed on public charge stations (where it should only take me 1 hour to recharge, it is now taking 1 hour 20 minutes. I originally thought that the battery warmer was running and drawing power - extending the recharge time. Then I looked at my home charger graph (below). Does anyone know what is happening?