Post #9386

Overpanelling is when you put more solar panel capacity in the system than your inverters or MPPT chargers can utilize. It is common to over panel by 25% but in the past two years I've been overpaneling by 100% or more. The advantage is that in cloudy weather you can still be assured to make reliable predicable amounts of power. Here's a screen shot of an offgrid system that simply stops making power once the batteries are full. If the batteries had not filled up at 14:00 the system would have continued to make the same power per hour until 1600. In this system we have capped the MPPT chargers at 80% of their capacity so 8.5kw and feeding them with 26kw of panels. A few days ago it was so cloudy I couldn't see the shape of the sun, just a bright haze and we still made full power. You can never have too much horsepower on tap and you can never have too many panels on the roof.