Solar-powered Wireless ISPs are springing up like mushrooms thanks to cheaper solar panels, more efficient gear, and better monitoring.
While a simple WISP tower might consume 20 watts per hour (or 480 watts over 24 hrs), a full-blown cellular system can easily consumer 20 times that amount or more. For remote locations, solar and wind turbines are sometimes required and wireless ISP technology is the only cost/effective solution.
A battery bank is used to store captured solar power for using at night or on rainy / overcast days. Most consultants advice enough battery powr to last 4 or 5 days and still not be discharged more than 50%.
With a tower consuming 20 watts, we might need 4 days of 480 watts/day, multiplied by 2 (for 50% discharge). This means the battery bank capacity needs to be 960 watts times 4 or 3840 watts. To convert the watts back to amp-hours, we would divide by the battery voltage rating (12) so 3840/ 12 = 320 Ah total, that’s 4 x 80ah batteries.
The solar panel will need to be able to capture enough solar power to run your equipment for the day, as well as recharge your battery bank following a rainy or overcast period. It also needs to be able to do this during winter.
So if the example has 4 hours of sunlight to capture 24 hours worth of power (480 watts), thats a basic requirement of an 120 watt solar panel. (480 / 4 = 120 watts per hour).
Of course details and requirements of each site can vary widely, so it’s always smart to get expert advice.