power demand on arduino camera trap project

JonnyA:
Hi,

I've been using an Arduino Uno board to run a camera trap. The input to the board is a parallax x-band motion sensor (powered via the board), and the outputs are the focus and shutter controls on my camera. I run the board on a 12V SLA battery. Everything works great, I now have two camera traps set up and I love the pictures I've gotten. The only issue that I use up a lot of power--I require a 45ah 12V to run my camera trap for ~2 weeks--hiking my camera into remote spots is a pain when I have to lug a car battery along with me.

Does anyone know how I could make this setup more power efficient? I can't put the system to sleep, because it needs to be constantly monitoring in case a critter shows up (they show up at all hours). Would switching to the Arduino mini save power? I heard it's more efficient, but the spec sheet looks the same and I'd have to step down the voltage from my 12V batteries to power it. Any thoughts on how I could significantly increase my power efficiency?

Thanks a lot.

Well converting to a bare bone type 328p board might help because you would not be powering the USB serial converter chip, the power on led, and the poor efficiency of the on-board linear 5 volt regulator. Find a switching mode 5 volt regulator and that should cut your continuous current draw maybe in half or more. After that using various AVR sleep mode might save more, but that would probably involve a rewrite of your code to make sure the sensor can 'wake-up' the avr chip and execute your program.

Lefty