Maybe that's all it is. But I noticed today that my battery light (the one that goes from purple to blue to green bars) that has always seemed to show the battery as discharging and recharging as I drive seems to be stuck on green indicating the battery is fully charged and doesn't seem to be discharging hardly at all. I say hardly because twice it dropped very briefly to the top blue bar before returning to green. I don't watch this screen much at all but I don't ever remember seeing it stay on green for basically an entire 20 minute trip. Anything to worry about? Or I am just being paranoid? BTW, it is a 2006 Prius with about 106K miles.
You're being paranoid. I suspect it is cold, and you have the climate control set to a fairly high temp. So the ICE is running a lot to try to get warm enough to keep your cold booty warm and it's spilling all that extra juice into the battery--which keeps the SOC high (ie. Green). Nothing to worry about at all.
Here's something to try: in the evening, park facing outward. In the morning, as soon as it hits Ready, floor it and drive aggressively. You should see a two or three bar drop in the battery gauge if you can put in a mile or two this way. When the car first starts up, it relies heavily on the battery for propulsion to limit emissions. If you have been letting the car idle warm-up in the mornings, that could explain the high SoC, but usually the car will stop charging and simply idle at 6 bars.
