Now the weather is cold in Chicago the ICE runs a lot more to warm up. I am constantly getting an almost full charge on the HV battery. Does the Prius use battery power more aggressively in this situation? It does not seem to, I still have a hard time keeping EV mode even when the ICE is warm.

Thanks in advance Robert

Robert,

It's hard to stay warm in the windy city (I was born and raised in Chicago). The ICE runs extra to stay warm as well as during the warm-up cycle. Since it is running already, the extra energy is used to charge the battery (as long as there is room) so it tends to stay in the green. The Electric is used for acceleration aid but you generally dont notice it unless you watch the graphic (don't, watch the road for safety).

JeffD

jdenenberg is not quite correct about the ICE running and charging statement. If you are quite perceptive you can tell when the ICE is running to warm up and charging the battery and when it is just spinning free to warm up.

Case in point, at startup the system does a series of checks and self tests. If you power up and then watch the energy display you will notice that the ICE runs and there is a line from the ICE to the electric motor and then to the battery. Now, "feel" the car and listen to the ICE. Car vibrates a bit and the ICE sounds like it is working. Now, after a short run that power generation line will go away, but the ICE will keep running to warm up. Notice how the car vibrates less and how the ICE sounds less loaded. That is because the ICE is now spinning free and is not under the load of a generator. Oh yeah, when you are doing this, you should be in park and not trying to move or else you probably won't see, hear or feel what I have described.

Just because you are at a stop and the ICE is running does not mean that the car is generating power.

To address your battery observation; 7 bars isn't a bad level to be at. You are probably getting the additional energy from regenerative braking rather than anything the vehicle is doing. The Prius will not actively try to attain 7 or 8 bars. I also tend to get 7 or 8 bars when I have a lengthy downhill descent or a great deal of opportunity for regen braking when driving in the city. In general, the car will work to get your battery charge level down to 5 or 6 bars from where you are right now.

It has been said:
Hybrid drivers come in 3 flavors, greenie, techie and cheapie. Pick any 2.
2005 Prius, Melinium Silver over gray, package 5 (AI)