Drove back from Niagara last night in the storm and I thought I had plenty of charge left. I had to top off at a public station for an hour and even then, I barely made it home. I was going about 50 km/hr on both the freeways and highways and yet my average Watt/hr usage was up to 300 when normal driving it is around 200. It appears that the car uses a lot more energy to drive the wheels in the uncleared snow on the roads than I thought. An ICE would just need more gas as well. Something to be aware of when driving in a snow storm. I would say allow a lot more of a buffer than normal.