I'm a student, I am a beginner with beaglebones. I have a project and in the project we have a BeagleBone Black connected to a battery and solar panels.
It will work autonomously, and the beagle will send datas by the 3G network through an 3G usb. 
What I want to do is to save as more energy as it's possible. What I thought first was to switch on hibernation or sleep mode the beaglebone. To switch on hibernate/sleep mode and then wake up the Beagle every x seconds or minutes or anything else. 
So I want to know if it's possible and if there is an OS more adapted for that use. 
I succeeded to disable the usb chipset and then to reactivate it several minutes later.
Thank you if you can help me !
For the beaglebone black, I was able to do this using the rtcwake function. There are several different modes. 
For instance, if you want to put the BBB in sleep mode for 10 seconds and then wake back up, you would enter the following command:
sudo rtcwake -u 10 -m standby
sudo rtcwake --help to see all options.
Hibernate a BeagleBone Black