Thanks for checking out my first project. It took 4 months to prototype it, as I had to go through 3 circuit board revisions before I had the working product.
I had the prototype working quickly on a breadboard, but what kept on messing up was the way I designed the schematic in KiCad. Once I redesigned the circuit so everything was connected correctly, it took one more revision to realize that on the footprint for the BMP180, I had the pins reversed.
Power consumtion is almost nill. This unit will easily run for 6-12 months on a single AA battery. I have been using the same AA battery thoughout the prototyping, and agter 4-5 months it's still sitting at 1.35Vdc. Coupled with the NCP1402 boost converter that can run down to 300mv doesn't hurt either. Most of the time the arduino is in sleep mode, only awoken every 8 seconds by a watchdog timer to poll for new sensor data and display it.
When The final version was working, I was estatic, but then it started to short out. Come to find out when I washed off the residual flux with a 50/50 mixture of acetone and rubbing alcohol, some of it got into the female headers I had on the board for the display. Once I removed the female headers and soldered the screen onto the bord directly, it came back to life. Come to find out the mixture was shorting out at the base of the female headers, and corroding the copper inside of the headers.