My guess is that you will see the Prius affected by cold weather more than the FEH. Don't let yourself get frustrated this winter, things will get dramatically better in the summer.

I also have a commute that has a long downhill and then uphill. The key to maximizing FE is on the downhill side. Keep your speed at 39 or below. If your ICE is warm enough, it will shut off completely when you glide. At speeds 41+, your ICE will have to idle.

If your downhill route is on the highway and you can't go that slow, then consider looking for another route. I switched from the interstate to a road that runs along side the interstate. The trip distance is the same but FE went from 67 to 75 in the summer. In the winter it went from 57 to 60. The cold air makes the ICE run more often in the winter so the FE difference between summer and winter is pretty dramatic.

Good luck.

Dan

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