The Prius Plugin allows for fifteen miles of pure electric driving of speeds up to 62mph.
The charge costs four times what ever your electric house hold charge per kwh is. Ours is 10.24p per kwh so a charge costs about 40p.
This is great in the summer. The issue is cold weather / winter.
Cold weather leads to misty windows due to breath. Cold weather leads to cold cars in the morning which require heat. Front passengers have a heated seat, but rear passengers need the heater on in the car.
Turning the heater on does two things. Turns on the petrol engine and takes one of those electric miles off of your range immediately.
You still get a good average mpg during winter. But its about 25 – 45% worse than summer.
Drops to an average (for us) of 50 – 60 mpg down from high 80s mpg.
Its good. Just much better in warm weather…