The support, ready for panel installation:
Sixteen 280 Watt Grape Solar panels.
The inverter, a PV Powered 4800 Watt, is a solidly made unit which can produce power even when the panel output is very low. I've observed it making as few as 50 watts before shutting down as dusk.
True, 50 watts is insignificant. But the system's low light efficiency pays off on a cloudy and foggy day like today. The system produced on average 400 watts under a solid overcast, and 4kwh for the day. That alone would be enough to reduce our electric bill by 10%. But of course a solid month of rain would be rare, and in normal weather the system should produce 500kwh/mo.
The early results are encouraging. The system has been running 3 weeks through a variety of weather conditions. It has averaged 19kwh/day, which equates to 570kwh/month. That should result in us having electric bills near zero for 2 - 3 months each year and substantially reduced ones for the remainder.
PV Powered has a great website which monitors the inverter and records the output. You can then download a variety of performance data, like the chart on right. It also monitors for any problems that might develop.
As we accumulate more data, I will update the results here. Update. I increased the size of the system, click here to see it.