I’m sorry.. I’m positive this has been posted before but I can’t find in through many search combos.

Ice is coming back on often because it’s trying to keep itself at optimal temperatures in colder climates. With short drives in cold weather, it will be a sand pounder for a bit. These vehicles are best when driven far for long periods w/o uphills. For the time being you should check your tires psi to see if it help improve mpgs

 

No. It's because the ICE (internal combustion engine) is running more. Colder temperatures will reduce your MPG significantly for short trips in an urban environment. This is because the ICE is running and consuming fuel in order to warm up during a larger proportion of the distance and time traveled. MPG is greater during the warmer season because the ICE warms up more quickly.

See Gen3 Warming up stages by ken1784.

During the summer, when temperatures are seldom below 70 degrees F, I can usually get between 65 and 70 MPG commuting around town using hypermiling techniques. During the winter, this drops down to between 50 and 55 MPG. Without hypermiling, MPG will typically be what you are experiencing for short commutes - somewhere between 40 and 50 MPG. On longer trips (greater than 20 miles) you will notice that your MPG will return to normal during the later part of the trip, even when it is cold. That is because the ICE usually takes only a few minutes to warm up, after which the vehicle operates in the higher efficiency states (described in ken1784's post) during most of the trip.

It is reported here in PC that using an engine block heater improves fuel efficiency for short trips, but I cannot vouch for this myself since I have never used one.

 

It's cold. It's wet. It's winter:
Why mileage gets worse in winter

And your trips are short, too short for the engine to fully warm and then start getting good MPG. For short winter trips, your MPGs seem normal:
Fuel economy complaints/queries? Please copy, paste & answer these questions, esp. if you're new

Your short trips are also not giving much time for the engine to push the traction battery SOC up to its normal 6 bars. Low speed stop-and-go city traffic tends to drag it down, while steady highway or arterial speeds tend to help restore it.

The fuel economy questionnaire above was written mostly for new drivers with fresh young cars, so it doesn't cover older-car issues such as excessively dragging brakes, or EGR clogging (a head gasket risk, not an MPG issue).

How many miles are on this car?

As for the tank getting low, note that the bottom of the fuel gauge is not at the real bottom of the tank, there are a couple gallons of safety margin left below the last warning and beyond Distance-to-Empty's first showing of 0 miles remaining. But don't depend on this to go any specified distance. While the margin should be good for about 100 miles of single-trip distance in the best MPG conditions on warm dry flat roads, there are very many ways for it to come up very short of that, and winter and mountains present many of those conditions.

 

Welcome, Tori. Those numbers look very normal to me for those conditions as explained by the above replies. Warmer weather and longer trips will give you better numbers.

And actually, you're very close to the middle of the curve at Fuelly. 2011 Toyota Prius MPG - Actual MPG from 663 2011 Toyota Prius owners

 

Yes and yes.
AND.....unless you are coasting down the side of a big mountain, the gas engine is the ONLY source of energy to make the car go.
The gas engine supplies the enerty to turn the wheels.
The gas engine charges the HV battery......which then later helps turn the wheels.
The gas engine gives you heat when it is cold.

There is no magic with a hybrid. It is just a bit more efficient.......in some/most situations.

 

One more thing is that the cabin heater — the thing that blows warm passenger air — requires heat generated by the engine.

If your cabin heater and ICE are both OFF, the instant you turn on cabin heat, the ICE will start up. The AC is electric but the cabin heater is not.

 

Delete

 

And then winter blend gasoline.