New to me Prius, not good mileage :(

Yeah, at idle AC will deplete your battery pretty quickly. How quickly depends on how large the difference between ambient temp and the temp you are requesting is.

 

allowing to deplete the HV battery is a sure way to hurt the trip MPG and kill the battery down the road too.
the EV button is mostly a gimmick, but a bunch of new prius owners overuse it a lot thinking they have an EV. They don't, they have a hybrid.
when i start my trip, i push the gas pedal so ICE starts immediately and gets warmed up quick, so battery doesn't go flat as soon as i need acceleration and the engine is still cold.

 

I have to back away a bit from my previous statement. I just left the Luke AFB clinic and ran over to the satellite pharmacy. I was in the drive-thru line for just over 7 minutes when the engine started. I had put it in gear 4 times to move up, but never came out of EV mode. So my take-away is that it probably would have lasted around 10 minutes before starting had I just sat idling in the clinic parking lot. It added 1 bar before shutting off. I was then in the line for another 5 minutes and it didn't come back on until I pulled away. I drove under 4 miles and just over 4 minutes at 25-45 mph when it was back to 6 bars. It fluctuated between 6 and 7 bars the rest of the way home (15 miles) at 35-50 mph, except for about 4 miles where I was in EV mode at 35 mph. There it dropped to 2 bars until I accelerated to cross an intersection. The end display showed 55.4 mpg for that part of our drive. So I guess there are times when the battery can lose its charge fairly quickly. I have no idea why it started after 7 minutes starting with 6 bars and then didn't start during the next 5 minutes with only 3 bars.

 

That's a good point. We keep ours set to 74° and it's very dry here, so even at 80° outside, the AC probably doesn't work very hard.

 

Dry in AZ? Say it ain't so!!!!

 

I'm so glad I can't. Our multiple annual trips to Florida and Georgia, even in months like Feb/Mar, are difficult because of the humidity and insect population. Florida isn't quite so bad, but the evening baseball games in Georgia put us out in the open and we come home covered with No-See-Um bites.

 

My 2011 can sit with the A/C on for a long time after I stop before the engine come on.

The OP should not be using EV mode -- I only use it when I want to reposition the cars in the driveway. EV keeps the motor from coming on when I just want to move the car 20 feet.

At 70 MPH mine start to drop off on the MPG.

I would also surest that the only accurate way to determine MPG is to calculate a few tanks using the actual gas purchased and miles driven ...