What About That Solar?

Yeah How about it.

Being that I work for a software company that builds software that allows users to essentially build their own apps for their own data analysis, I decided to do just that with my own solar data.

Up to this point I’ve been downloading the data from my inverters and importing it into Excel spreadsheets. From there I did a little formatting, totaling and graphing to produce the data visually for consumption here. In that process I specifically did two things that I’ve since changed:

1. Based all my month calculations around my electric billing cycles
2. Used only the data from my inverters.

In moving over to building my own app with our software I’ve changed things up a bit. Now I’ll have the ability to look at my data from a calender month standpoint OR electric billing cycle. I’ve also increased the amount of data I’m processing by recording the actual values of my meters each month and each billing cycle (Jen thinks that part’s crazy).

I’ve always known the data from the inverters had a level of inaccuracy. For example when the power goes out, that days production (if any) is completely lost from the inverter record. In addition, some days are lost without reason. Fortunately none of that gets by the solar meter (I actually have three power meters on my house. One measures total solar production. One measures power to the grid and one measures power from the grid). If it’s produced, the solar meter records it permanently. That’s why I go out twice a month at night and record its value.

Blah, blah, blah. Where’s the data?

I have it. I have a lot of it and am slowly processing it. I’m also still tweaking the app, so the representation isn’t everything it could be.

I’ve come to learn the inverter data is nearly unreliable (the meter/inverter variance for January 12 was 134 kWh), so I’ve been focusing mainly on the meter values which I’ve only recently started recording. What you see above is total monthly production and consumption based on my meter reads. I didn’t read the grid meters for January, so that’s incomplete. For February I produced 591 kWh, consumed 324 kWh from the grid (that’s from grid value minus my to grid value), for a total monthly use of 915 kWh. In March you can see we did even better with our production/consumption ratio (something else I should calculate) – 833 kWh produced, 172 kWh from grid, 1005 kWh total consumed.

Going forward most of my analysis will be based on the meter data, which is basically starting over after a year and a half of production. I’ll probably do the analysis with the inverter data too, but it’s a lower priority.

One thing the inverter data does well is show me daily production.

Assuming I have the data for all the days…

The green and blue in this one represents the two inverters I have for my system. One is bigger than the other (the green one) and attached to more panels, so it produces more.

So that’s where it is with the solar stuff. As I said I’m still tweaking, so I’m not likely to have a whole lot soon. When it is done, it will probably be a flood of graphs and charts.

Stay tuned.

-b