- #1

Tone L

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- TL;DR Summary
- Calculating daily energy consumption of raspberry pi versus daily power regeneration of a solar panel.

__The objective:__Determine the daily power draw of a Raspberry Pi (Watts per Day) and determine the average daily power generation of a solar panel. Will energy generated be greater than energy drawn?

Lets begin,

I have a 9 Watt, 18 Volt solar panel. This solar panel is charging a sealed lead acid battery (18 V to 12 V converter in-line), the battery is a 12 Volt, 12 Amp-hour battery. There is a Raspberry Pi (RPi) that is powered off this battery.

Consider, the RPi (3B+) requires 5 Volts to run, and on average I directly found it's power consumption is

**3 Watts**while I am running my processes. So, in 24 hours the total daily usage will be 72 Watt-hours per day (24 hours * 3 Watts).

Consider, the solar panel operates with full sunlight 6 hours per day. So 6 hours * 9 Watts = 54 Watt-hours per day generated.

Is my thinking correct, is there another way to approach this? A LOT of assumptions but, first I wanted to smooth out the details. I haven't considered partly cloudy conditions, etc, it is an average. But, there is a disparity of: 54 watt-hours per day - 72 watt-hours per day = -18 watt-hours per day.