Drunk Dumbass
New Member
Hi everyone! I'm new to the world of electronics but I have an idea for a project and I was wondering if one of you old salts wouldn’t mind reviewing my calculations and let me know how they look. This is a pretty simple project so it should be a quick easy review for those of you who know what you’re doing.
I have a 12 volt, 10 LED light that I would like to hook up to a battery & solar charger with a photocell switch so that the light will come on at night and shut off during the day.
The current draw for the light is .08 Amps. So 12 volts X .08 Amps = .96 Watts
I figure during the winter it will get 8 hours of good sunlight for charging and then the light will stay on 12 hours at night. There will be some hours in the morning and evening when the sunlight won’t bright enough for charging, or dark enough to turn the LED on, so I’m not counting those hours.
So the amount of energy the light uses each night would be .96 Watts X 12 hours = 11.52 Watt-hours.
Size of the solar panel needed would be at least 1.44 Watts, that’s 11.52 Watt-hours / 8 hours.
And the battery would need to be at least a 12v .96ah battery.
So a 5 watt solar panel and a 12v 5ah battery should be big enough to give plenty of safety margin to cover cloudy days and such.
Does this look okay to everyone or is it way off base?
I have a 12 volt, 10 LED light that I would like to hook up to a battery & solar charger with a photocell switch so that the light will come on at night and shut off during the day.
The current draw for the light is .08 Amps. So 12 volts X .08 Amps = .96 Watts
I figure during the winter it will get 8 hours of good sunlight for charging and then the light will stay on 12 hours at night. There will be some hours in the morning and evening when the sunlight won’t bright enough for charging, or dark enough to turn the LED on, so I’m not counting those hours.
So the amount of energy the light uses each night would be .96 Watts X 12 hours = 11.52 Watt-hours.
Size of the solar panel needed would be at least 1.44 Watts, that’s 11.52 Watt-hours / 8 hours.
And the battery would need to be at least a 12v .96ah battery.
So a 5 watt solar panel and a 12v 5ah battery should be big enough to give plenty of safety margin to cover cloudy days and such.
Does this look okay to everyone or is it way off base?
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