Since the PowerWall install, I've been paying closer attention to my house PV production. Normally, I look at my Curb monitoring on production as the sum of the "guerrilla" system (currently 29 ~245w panels each with an Enphase M215 microinverter) and the roof top system which is a nominal 8kw with 26 ~300w panels on a SolarEdge string inverter. Looking at the roof top only, I was struck that there was a flat top on power vs time. About 5kw. So, I went out and examined the inverter. Sure enough, "5kw". With good sun, it looks like it is spending about 90% of the time during the best production hours pegged out at 5kw.
My experience with installers has been very poor and the one that did the SolarEdge was especially flaky. So, I have no hope of getting the installer to fix it. Something like "GoGreen".
Now, to decide whether the inverter is worth replacing with a more powerful one. If so, how powerful? I find 6kw listed but haven't seen a 8kw.
Typical "flat top" from too small an inverter:
Benjamin's SMA system in Dallas is rated at 8400 watts. It uses two Sunnyboy string inverters:
ReplyDeleteSB4000TL-US22 867 and SB4000TL-US22 555. They peak at slightly different times. Each one has an emergency switch that can be turned on when the grid is down so power can be provided to an outlet. (I think he said it is something like 1 kW.) Your system sounds like the one Mike has on his house, with limited power during max solar output times.
That looks like two 4kw inverters. I wonder what the last three digits mean. I know that he has two sets of panels pointing two directions. Same number of panels for each direction?
DeleteI should know but will ask anyway: What is Benjamin's max observed power output for each inverter? With good sun, I imagine he sees a peak over an hour or two period. My inverter limited flat peak may last 3 hours.
The last 3 digits may be serial number. Here is a graph showing the Feb. data. (won't let me post image, so here is a link.)
Deletehttps://imgur.com/ZvDVe0G
I believe that chart shows me energy per day for each inverter. My interest is in power vs time during the mid day.
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