Wow - ambient external temperature REALLY matters for MPG

In my case, 2 other drivers took it on a 1400 mile round trip and I had to get everything set back the way I like it. The morning was a little cool so I had the fan a little higher & wondered what happened to the mileage.

 

come on tell us what you do to improve the MPG in your Prius , would love to hear it

thanks

 

snowbird

 

That's a great non sequitur
And isn't this thread from 2016

 

I agree that cold temps affect MPG (along with slightly reduced energy content in "winter" gas). I am also of the opinion that, at least on highway trips, wind speed and direction can substantially increase/reduce MPG. I came to this conclusion after taking numerous 100 mile (each way) trips following identical routes in similar temps. Wind direction was the only reasonable variable that could improve/diminish as much as 10 MPG. Prius is more aerodynamic than most vehicles but still susceptible to drag.

 

I've only had my 2017 Prius 2 since October, but based on several years with my 08' gen II, as a general rule your Prius will see its best mileage when the ambient temps are in the 60's-70's (deg F). As all Prius(s) manage the main battery very carefully (which is a very good thing..) at these ambient temps the battery is happy and the cars charging system isn't trying to modulate the charging current to try to bring the main battery pack to its optimum operating temperature in cold weather which means more load on the ICE for charging, and conversely when in high outside temps, the system isn't limiting the battery current to avoid overheating which forces the ICE to handle more of the driving load.

 

Another good thing about the 60 and low 70 degree temperature is you aren't heating and cooling as much and the return of summer gas.

 

I just bought an '18 Two Eco a few days back (I had a 2014 Prius C for 2 years before on lease). Temperatures in the first couple of days were in the high 40F range and I was getting well over 60mpg. We had a cold snap down to 20F and lower yesterday and this morning and now I am seeing 45-50 mpg. I forgot how much the Prius hates the cold. I only had the heater set to 70F too.

 

The further you have to drive the less impact it has up to a point. What I mean is, if your journey is less than about 5 miles in the cold weather it's very low mileage. After that, it improves to lower mileage than on warm days.

 

I bought my 2016 Prius four in November of 2016 and was still a new car even though the 2018 were coming out. I have never driven it in temperatures above the low 40 degree mark. It will be interesting to see how my mileage changes as we go into spring and get the summer blend of gas. We will be in the low 50's here today. I have even been impressed with the cold mileage MPG compared to my old Gen 2.

 

Most of the experts on here suggest that even in sub-zero temperatures the Prius returns better mileage than similar pure ICE cars.