Hi,
I found this tutorial to send an ESP to deep sleep --> ESP8266 Thing Hookup Guide - SparkFun Learn
Sounds quite nice to me, but still the ESP is sucking 8 mA.
If I use 3xAA with 1.2V/1.900 mAh it gives me 20 days of power, but thats not enough.
I'd like the device to run for at least one year, calling a web-service every 5 mins.
Is there another "sleep-even-deeper" mode that is equally simple to realize ?
Or do I need much more knowledge that I do not have yet ? 
BR
Gawan
I'd like the device to run for at least one year, calling a web-service every 5 mins.
On 3 AA batteries? I'd like a nude blonde supermodel to drop by with a million dollars, too. I bet I'm more like to get what I want.
Gawan:
Sounds quite nice to me, but still the ESP is sucking 8 mA.
You can reduce the 8mA by disabling the power LED. According to this blog post, the SF Thing can go as low as 78 uA in deep sleep. This may not last 1 year but it should last months instead of days.