S20 yawe ikora 1.5W. Niba ushaka 45Wh ku munsi, uzashyira izuba amasaha angahe?

The power output of the device is $1.5 \text{ W}$.
The desired energy per day is $45 \text{ Wh}$.

The formula for energy is:

where $E$ is energy, $P$ is power, and $t$ is time.

To find the time, we can rearrange the formula:

You will need to put it in the sun for 30 hours.

The final answer is $\text{30 h}$.