Re: Can someone explain where the 52% derating comes from?
Please remember too, that the 52% is overly optimistic. One reason is that as the controller ramps down as the batteries become fuller you end up leaving potential power on the table. Unless you can manage your power very effectively such that your batteries come full just as the sun goes off the Pv it becomes hard to get even the 52%.
I like to use the 50% rule of thumb times 4 hours. Even that is probably too generous day in and day out.
Just for the record, we use ~ 6-800 wh/day, from 400 watts of panel. On a really good day we can generate up to ~ 1.5 kwh/day, but I like to use the average. (400/2*4=800 wh)
Please note, being a moderator does not add any weight to my opinions 300 watts Siemens/BP panels,plus a Sun 90,, making ~400. ~30 amps into Rogue MPT-3024, 450 ah of Trojan T-105, Morningstar ts300 inverter, a Tri-Metric meter.a collection of antique generators, plus 2 Honda eu-1000i's (also a BS2512 IX controller) and assorted other stuff!