Phil Forest flipped our 4.76 kW Sunpower PV system on during the afternoon of June 9th, 2011. At the end of the day June 8th, 2012, the system had produced 6,694 kWh. On the following day, it made 22.5 kWh, so take half of that for a full year's worth of production - afternoon to afternoon - and the total is 6,705 kWh. I'm really pleased and not a little surprised at this total, it's significantly over what we predicted. The system has some winter shading, too. Nonetheless, the yield was 1.41 kWh/W/year, and during the time when I had a small (1.06 kW) system at my NH home in the late 1990s/early 2000s, that system never made over 1 kWh/W/year. Likely a cloudier climate, and I know this past year has been sunny (Eliakim's Way PV production is up 6% over the first year), but some of this has to also be technology improvements. Sunpower claims their technology is more productive in low light conditions and high temperature conditions than their competitors, and just maybe they're right!