I'm using ordinary Energizer alkaline.

I just got my 256 MB CF card. I installed it and battery showed up as empty. I cycled power and it shows full battey power. A glitch. I've noticed that sometimes on powering up the device it behaves strangely, but it's always fixed by cycling power switch and all is well.

I'll let this run a few days and see how many more I can get from this one setup of batteries.

Perhaps the discrepency between those getting lots of pics and those getting "just" 100 on a set of batteries is the ratio of night to day pics. 75-80% of mine are daylight so far, so maybe the flash really drains the batteries. The guy posting all the pics appears to be all at night, so I wouldn't be surprised if I only got 100 nighttime pics. Also, temps here have been in the 70s-90s (F), so maybe temp is also a factor.

Also, being an electrical engineer, I don't see how the camera would know the difference between a 12V solar panel and a 12V external battery. An electron is an electron and it doesn't tell anybody where it came from. I've also toyed around with the idea of just ganging up 2 fat 6V batteries, or one 12V lead acid battery to the solar panel jack and it should run for months. Obviously you'll need rechargable AA for inside the unit. And you'll need to weatherproof the external battery pack. Probably by the time you do all that it may cost as much as the solar panel.

Overall, still very pleased with my $240 purchase.