I have 3 quotes in hand. Because I am in a new (to me) house I am estimating my usage to be 1,000 kWh per month. My roof faces 160 degrees and there is no shade.
Everything Solar has quoted 22 325w Q Cell panels with a SolarEdge inverter. Predicted production is 10,446 kWh for the 7.15 kW system. Efficiency of 71%
SolarRay proposes 28 300w SunSpark panels with an SMA inverter. PP is 13,277 from the 8.4 kW system. Efficiency of 76%
SEM proposes 27 320w REC panels with Enphase Micro Inverters. PP is 13,961 from the 8.64 kW system. Efficiency of 78%
I have calculate the system efficiencies by dividing the Predicted Production by the Rated Production (system kW x 365 x 5.67 average hours per day).
Comments are welcome. Why are the efficiencies so different? More downtime for the Q Cell/SolarEdge system?