In many of the locations we work, there is limited to no power - or at least a reliable source of power.  In these situations, here are a few recommendations:

NOTE: these are just some that we have seen used before, always look for local solutions first as they will be the cheapest and ultimately best options.

Solar Solutions:

Local Charging Stations:

 

Tips for increasing Battery Life:

 

Good Questions to make sure you are asking: