Powering a phone on solar

Using an simple phone consumes approx 3 kWh of energy yearly

Three Watt solarpanels will produce that amount of energy yearly.

2 555 Wh per year

In this way you have assured that you create all energy used by the phone on a yearly basis

 

A samsung galaxy S3 mini has a 7Wh battery

You charge it once a day for a year that is 7*365= 2 555 Wh or 2,5 kWh per year

With just 3W solarpanels  the phone is covered yearly

SAMI8190NWH
Samsung Galaxy Note 4 batteries has 3.85 battery voltage and operates at 3220mAh

That gives us 12.4Wh per charge times 365 days gives us 4.5 kWh per year

You need only 5W solarpanels to create that amount of energy early

 

One Watt solar panel in Sweden produce aprox 950 Wh per year (on an average depends on weather etc.)

You have the Watt for 15 years so it, creates 14,2 kWh which removes over 11kg of CO2 (northern European electricity mix)