Plug-In Prius: real winter driving

That hasn't been my experience. I tested it tonight too. With the heater set at 72 but off (no fan), I drove to my association meeting... all in EV. The Prius sat there for 2 hours. When I left, the outside temp was 27 and the coolant 51. The 4-mile drive home was all in EV. The engine never fired up.

Setting the temp to any number is how you prevent outside air from being allowed in. Nothing else will happen when the fan isn't running.

Could your observation have been different due to the AUTO button being active or not being ECO?

 

-2°F in EV speaks for itself. I wanted to know if the battery-pack could deliver the power needed for my daily commute in such extreme cold conditions. It did... and I'm quite thrilled how well the video turned out...

The ride itself wasn't exactly warm, but I did it without wearing gloves for the first 24 minutes of driving. The heated seat on high does a remarkable job. The point was to find out how well the EV would perform, so I kept the heater off.

9 miles of electric-only driving was what ended up being available. I fired up the engine shortly before the battery was fully depleted of EV, not wanting the upcoming hill climb at 55 mph consume lots of HV capacity (electricity is used to allow the engine to gracefully speed up).

Watching the video to the end, you can see close-up display photos of the outcome. The total distance traveled was 17.2 miles. The result was 117 MPG. That took approximately 3.0 kWh of electricity (including charging losses) along with 0.15 gallon of gas.

That would be impressive even if wasn't -2°F. I still miss summer though, since EV works better then.

 

Think of it like the engine input. There are alternate air feeds, one for "cold" and one for "hot". LO uses the "cold". 65 and up uses the "high".

You can hear the switch too, in really quiet conditions. 65 allows air to pass through the core and use the most internal source of air. That's why you get a hint of heat even when the fan isn't running. Remember, there is still some waste heat from the traction motor, not just the engine. LO bypasses all that, sucking in outside air exclusively.

RECIRC is totally indepedent and you rarely ever want to use that in the winter, since that air gets moist from your own breathing rather quick. Outside air, either direct or indirect, is needed to keep the windows clear.

 

In reality, it probably doesn't equate to much. But at -2°F, even a remote trace of heat is still better than nothing.

It hadn't occurred to me to actually try to quantify it. Perhaps I'll pop the hood before & after an EV drive sometime.

Unfortunately, I just wrecked my laser-thermometer. Be extremely careful inserting a new 9-volt battery. I had it backwards and the device actually exploded. Nasty smell. Pretty upsetting of a preventable mistake. I guess it's time to go shopping.

 

Winter is over. Yeah!

Here's the last of the videos...

...and the real-world data from that particular drive: