2018 Prius Prime no longer getting 25 miles per charge

Batteries discharge faster when they are cold. To make matters worse DC heaters are not very efficient.

 

The Prime has a DC heater?
Heat Pump and engine coolant yes but DC??

 

Seat heater and any defrosters will be Direct Current Resistance heaters

 

i thought the ac was ac

 

Are you checking cold tire pressures? Your garage might be heated and register spec tire pressures, but once you go outside into the cold that air's going to contract. We've been over-inflating by a bit to get spec pressures at low temperatures (because I think the spec is set at not-20F).

That said, our Model S is (very) noticeably slower when it's cold and I find myself not getting to my normal 275 Wh/mile rate until 30-40 minutes of driving, even with preheating. I've been assuming the Prime is pretty much the same.

There's also a battery heater that is probably eating some of that power in both cars (although the one in the Prime is supposed to only come on with a charge cable attached, so I'm not sure).

 

First time since last Dec, my EV range GOM returns to above 25miles. Good timing that the gas price has gone up substantially in last few weeks.

 

My GOM hasn't gone below 29 since I got mine in Jan. '17. Then again as @HPrimeAdvanced says, "I drive like a crippled snail" lol

 

Yeah, if ICE stays off when I first start the car in morning, I can usually keep the GOM above 25. Today was the first such day, ICE did not start when I first turned on the car at 16F outside.

 

I get 45,3 miles (72km) EV-only everyday from work

 

Since the weather has warmed up to 60° here, my GOM is reading 31 to 32 miles these days. Not bad for a 2 1/2 year-old prime.