They are power hogs for sure. However, sitting in my house after 3 hrs of running I had ice in my diet pepsi cans. Pre cooling is essential, and having some ice paks or frozen water bottles are a huge bonus....remember that airflow is essential...so leave some space around stuff to circulate the air. Also, remember to unplug when stopping the rig. The icepaks and frozen water bottles will keep things cool while stopped. I used mine alot and think its fine for a couple of days toolin around the backcountry.
Power source is the jeep mainly. It will be in an air con'ed Jeep during the day and it gets cold here in the night....so its all good. Already used it a bunch of times. At some point I am getting a real fridge I can keep running around the same size as the power chill...but until then I am running what I brung. I got it on sale at wal mart for 79,99 cdn so that was a steal!
Another group of items we are getting is the springtail barricade and cargo mounts for the rear of the jeep. The cargo mounts hold ammo cans, which one will be recovery gear, the other will be a tool box. my first aid gear is under the cargo area in the back. The springtail gear is AWESOME...and HIGHLY RECOMMENDED.