I'm looking for confirmation to see if this battery and this solar panel will cover my needs for a remote timelapse project I'm setting up. The timelapse will run 6 days a week for 9 hours. My area gets 4 hours of good sun a day.
So far, based off all the reading I've been doing, my math looks like this:
The device's power consumption:
12V battery x 275mA device current = 3.3W x 9 hours a day = 29.7Wh + 10% solar controller losses = 32.67Wh
For a 1 day reserve (to try and get past any rain that might stop charging), this upsizes my power consumption to:
32Wh + 30% reserve = 42.47Wh
For battery capacity, I know I shouldn't drain the battery more than 50% to preserve it's health.
42.47Wh / 12V = 3.5Ah x 2 (for the 50%) = 7Ah battery
In order to size a panel to charge this system:
12W panel x 4 h sunlight = 48Wh of power
48Wh of power is within my 42Wh of consumption with upsize to charge.
So I'm looking to confirm:
- Is my math right?
- Will the 12W panel (at 48Wh) cover my 42.47Wh power consumption?