Year to Year production

This is about 4 and one half years into my PV system’s production. I am located in Southern California. We have pretty good solar exposure but the months of May and June a plagued with a lot of low cloudiness during the morning and evening hours which cut down power production significantly. I am very pleased with the performance of the 21 LG 300 Neon2 black panels and SolarEdge SE7600 inverter. It has been relatively free of trouble with only one optimizer failing during that period. It was quickly assessed and replaced with minimal loss in production from the panel of about one week. Here is a plot of the performance by month over the period. The green carat marks indicate average production over the first 3 years.

Is this a 3ph system? What is the average annual production per kw installed modules? What is the difference that you estimate between the production estimated by the inverter and the estimate of the meter? Are there any shaded panels? Do you have any voltage drops at panel level (i.e. pid).

In my case, with a 10kw 3ph system with some shade and restrictions on orientation and azimuth I am not happy at all with the Hanwha-qcells polycrystalline panels which suffer with pid issues. I am ok with solaredge 10k and the difference that I estimate is 2.5% between the inverter and the meter. I had one optimizer failing during the installation.

If I would design the system now, I would choose an inverter with integrated AC-DC surge protection, PID recovery and with the option not to use optimizers for all panels (they do consume energy!). I would definitely not choose the same pv panel maker.

Nice chart but that green indicator doesn’t look like the average of the first 3 years production. Take March for example. The green marker is below each of the first three year’s production, so it can’t be the average of those three years. Same for Apr, Jul and Sep where the marker is below each of the first 3 years.

You are right it is actually the first four year’s averages. I don’t remember the last time I updated them. The graph is from the SolarEdge monitoring web page. They provide access to the data for download at 5 min intervals. I kept charts in excel for three years and then quit doing them because I was very satisfied with the performance of my system. I ordered the system on line but selected the panels, inverter, rails and mounting system which was sized by the provider. At the time they were state of the art. I am very pleased with the system which has provided all my power with excess which paid all the fixed non-by passable charges. Basically I have paid the Electric Company nothing the past four going on five years and managed to collect a few dollar the first three years. Compensation for excess hours not redeemed for power use during dark hours is only a 1 to 3 cents per kWh.