Got a small project here in a remote location. There is to be a 2 volt deep cycle battery, the equipment to be powered from battery and solar panel to charge battery. The 2 volt battery puts out 55 AH. the max constant power draw from the equipment to be powered is 7.9 watts. Will a 30 watt panel at 2 volts be enough to run this system during sunlight and charge the battery for the equipment to run overnight?And, at 55 AH, how long can I keep a constant draw of 7.9 watts without a recharge?Thanks to all the input!
Will a 30 watt panel at 2 volts be enough to run this system during sunlight and charge the battery for the equipment to run overnight? Maybe theoretically, but you're going to have very little margin for losses and clouds. I'll bet it has very little power when cloudy. 7.9/30 = 0.26. So at 00% efficiency, you'd need it to be charging more than 25% of each 24 hour period. In a summer with long days and a climate with few clouds, you might make it. But I think you're very close to the edge. And, at 55 AH, how long can I keep a constant draw of 7.9 watts without a recharge? For an ideal battery: time = Q V / P time = 55 A h * 2V / 7.9W time = 83 hours So you've got pretty good margin on your battery.
o work out the wattage correctly, the panel needs to be sized according to how much power you are going to use. (Later on you're going to need a bit of info on each electrical item you need to be solar powered).
