abasile wrote:I have 360W (DC) panels with micro-inverters that max out at 320W (AC). I've noticed that some of the panels are now reaching the maximum 320W by roughly 10:30am, well before solar noon (~ 1pm). Even in mid March, I was seeing panels reach the max of 320W. This makes me wonder if perhaps the micro-inverters are a bit under-sized.
I'm now thinking that perhaps our micro-inverters (and inverters in other systems) may have been sized with the expectation of somewhat warm panel temperatures during the months with maximum sunshine. However, our moderate latitude, elevated mountain location (about 1870m above MSL, 34 degrees North) often gives us access to exceptionally intense solar radiation relative to our temperatures. (I was counting on this to offset at least a fraction of the production that we're "losing" to shading.)
This week, our PV production is noticeably lower than last week, roughly 7% less energy per day. We're no longer hitting the max of 320W at each micro inverter. The only significant factor seems to be the temperature and wind. Last week, our daytime highs were in the ballpark of 10C, with somewhat high winds that undoubtedly helped keep the panels quite cool. This week, we are seeing highs in the range of 20-25C, with little wind. So the panels are certainly getting quite a bit warmer, and thus producing less. As a result, the micro inverters don't appear to be "clipping" our output.
By the way, our SGIP application for the Powerwall 2 was conditionally approved for "Step 1", the largest possible rebate amount.
So we are looking forward to installation in June, or perhaps later if Tesla ends up further behind schedule on Powerwall deliveries.