Methods of connection from a remote site via mobile internet

I am proposing to set up power monitoring of the present three phase power consumption at a small university in Kumi in Eastern Uganda.
This is to be able to correctly size the battery, charge controller and inverters,
from the existing solar panel installation.
I plan to use EmonTX for monitoring but I need help in understanding how to make the data transfer to Emoncms over a mobile data network.

A gsm USB dongle can be connected to the emonPi http://guide.openenergymonitor.org/setup/connect/#5-connect-via-3g-gsm-optional