One of the satisfying parts of having a plug-in solar system is watching the generation data in the companion app. But monitoring is not just satisfying — it is also how you catch problems early and confirm your system is performing as expected.
What the app shows you
Most plug-in solar kits come with a smartphone app that connects to the microinverter via WiFi. The main things displayed are real-time power output in watts, daily generation in kilowatt hours, historical generation by day, week, month and year, and usually a running total of estimated savings and CO2 saved.
EcoFlow’s app, the Hoymiles S-Miles app and the Anker SOLIX app all work on this basis. They differ in detail and presentation but cover the same core information.
What normal looks like
On a clear summer day, a south-facing 800W system should show output rising from zero at sunrise, climbing through the morning, peaking somewhere between 600W and 750W around solar noon (roughly 1pm BST in the UK), then declining through the afternoon and dropping to zero as the sun sets. The curve is roughly bell-shaped.
On an overcast day, the peak will be much lower — perhaps 50 to 150W rather than 600W or more. But the curve shape should still be present: low in the morning, higher around midday, lower again in the afternoon.
In winter, the peak is lower and the curve narrower due to shorter days. A December peak of 200 to 300W for a well-positioned south-facing 800W system is normal.
Warning signs to watch for
Zero output on a day with visible daylight is the clearest warning sign. Check the obvious things first: is the system plugged in, is the microinverter powered, is the app connected to the right device? If everything looks connected but output is zero, check for a fault indicator in the app.
Output significantly below what you would expect for the conditions — for example, 100W on a clear summer afternoon when 600W is normal — suggests shading that was not there before, a dirty panel, or a developing hardware fault.
Generation data that cuts out at a specific time each day and then resumes could indicate a shading problem from a tree or neighbouring structure that is casting a shadow at that time of day.
Comparing to the calculator
After a month of operation, compare your actual monthly generation to what the savings calculator predicted. The calculator uses average solar yield data; your actual figures will vary with weather, but should be in the right ballpark over a full month. Consistently lower-than-predicted generation is worth investigating — the most common causes are unexpected shading, an orientation that is further from south than assumed, or a panel that is not perfectly clean.
Smart meter and plug-in solar
If you have a smart meter with a home display unit, you can often see your net consumption in real time. On a sunny day, watching your net consumption drop when the sun comes out is a direct confirmation that the solar system is working. Some smart meter displays show negative import when solar generation exceeds household consumption, which is a satisfying confirmation that everything is working as it should.