How to calculate solar panel power?

Question

Electronics

It is necessary to power a surveillance camera + Wi-Fi access point + night mini-backlight on the site of a private house. The access point consumes 2-3 W, the camera is slightly larger, the backlight is 0.18 W (it will only work in the dark). The total consumption is 6-7 watts.
How powerful should solar panels be? Is 15 watts enough? And what is the battery capacity?

Answer 1

consumption, (only not exemplary is better), multiply by one and a half (~ 70% total efficiency charger - battery - output converter) * 24 hours. is the daily intake.
you multiply five to seven times (reserve for non- or low-sunshine days) - you consider the required battery capacity.
you take consumption for three days (again, in reserve) you look at the insolation plate for your region in the plate - you consider the required power of the solar panel.
it is still worth picking up pieces of iron that can be directly powered from the selected battery.
Yes, and take a battery charger with mppt.
if the battery will be used in winter without insulation, then you multiply by the "winter" efficiency. Yes, and you look in the direction of lead, because the efficiency of frozen lithium is near the plinth.
it's just for the sake of it :)