The short answer
You monitor solar output mainly through your inverter, which records how much electricity the panels generate and usually reports it to an app or online portal. There you can see real-time generation and totals by day, month and year, and on many systems your self-consumption (how much you use directly) and export to the grid. Some setups add per-panel monitoring (with microinverters or optimisers), so you can spot a single underperforming panel. Your smart meter separately records what you export for Smart Export Guarantee payments. The practical value of monitoring is twofold: it shows the system is performing as expected against its estimated annual generation, and it helps you spot faults early — an unexplained drop can signal soiling, new shading or an inverter problem worth investigating.
Once your system is running, monitoring lets you confirm it is generating as expected and catch any problems early. Most of what you need is built into the inverter and its app — this page explains how to use it.
Key facts
- Main toolInverter app or online portal
- ShowsGeneration, often self-use and export
- Per-panel viewWith microinverters or optimisers
- Export meteringVia your smart meter (for SEG)
- Why it helpsConfirms performance, flags faults early
Where the data comes from
The heart of solar monitoring is the inverter. As it converts the panels' DC output into usable AC, it measures how much electricity is being produced, and most modern inverters send that data to an app or web portal over your home internet connection. From there you can typically see:
- Real-time generation — how much the array is producing right now.
- Historical totals — generation by day, week, month and year, so you can compare against the system's estimated annual yield.
- Self-consumption and export — on many systems, how much generation you use directly versus send to the grid.
Some installations add per-panel (module-level) monitoring using microinverters or power optimisers, which report each panel separately. That makes it easy to see if one panel is underperforming — useful on roofs with partial shading or where a fault could otherwise hide in the array total.
The distinction matters because of how panels are wired. In a basic string system, the inverter reports one combined figure for the whole array, so a single weak or shaded panel shows up only as a slightly lower total that is easy to miss. Module-level monitoring instead gives each panel its own line, so an underperformer stands out immediately rather than being averaged away. For a roof that is uniformly sunny this adds little, but where chimneys or trees shade part of the array, or where you simply want the reassurance of seeing every panel, per-panel data turns a vague total into a precise picture of what each part of the system is doing.
Understanding the figures
A few terms come up repeatedly in monitoring, and knowing them helps you read the data:
- Generation — the total electricity your panels produce, measured in kWh. This is the headline number to compare against your system's estimate.
- Self-consumption — the share of generation you use directly in the home rather than exporting. Higher self-consumption usually means better value, since you avoid buying that electricity.
- Export — what you send to the grid, which your smart meter records for Smart Export Guarantee payments.
It helps to expect a strong seasonal pattern: far higher generation across spring and summer than in winter, because of longer days and a higher sun. A low December reading is normal, not a fault. Judge performance over a full year against the annual estimate rather than reacting to any single day, which the weather alone can swing dramatically.
| Metric | What it tells you |
|---|---|
| Generation (kWh) | Total electricity the panels produced |
| Self-consumption | Share of generation you used directly |
| Export (kWh) | What you sent to the grid (for SEG) |
| Per-panel output | Whether any single panel underperforms |
| Annual total | Compare against the system's estimate |
Indicative guidance only; available metrics vary by system.
Using monitoring to spot problems
The most valuable use of monitoring is catching issues early. Because you have an expected pattern of generation, an unexplained drop stands out — output well below what similar conditions and the time of year would suggest. Common causes include soiling such as bird droppings, new shading as nearby trees grow, or an inverter fault. Per-panel monitoring narrows this down further, pointing to a specific module.
A simple routine works well: glance at the app now and then, and check the running annual total against the system's estimate. If you see a persistent shortfall you cannot explain by weather or season, it is worth contacting your installer to investigate. Many inverters and portals also raise alerts for faults automatically. Monitoring does not require constant attention — the system runs itself — but a light, occasional check ensures you are getting the generation you paid for and that any fault is found and fixed promptly rather than quietly costing you output for months.
Getting more from your monitoring
Once you are comfortable reading the basics, monitoring can do more than confirm the system works — it can help you use your solar better. A few practical habits make the data more useful:
- Shift usage into generation. If your app shows when you are producing surplus, you can run high-use appliances — the washing machine, dishwasher or an EV charger — during those hours to use your own electricity rather than export it.
- Watch self-consumption. Tracking the share of generation you use directly shows how well your habits (or a battery) are capturing the value of your solar, since used electricity is usually worth more than exported.
- Compare year on year. Once you have a full year of data, comparing the same months across years is a clearer health check than comparing different seasons, because it controls for the seasonal swing.
- Cross-check export with your supplier. Your smart meter's export figure is what earns Smart Export Guarantee payments, so it is worth seeing that the credits on your account match what you are sending to the grid.
If you add a battery, monitoring usually expands to show charge level, charging and discharging, and how the battery is shifting energy across the day. None of this is essential to the system running — it manages itself — but it turns a passive installation into one you can actively optimise. For most owners, a light touch is enough: confirm the annual total tracks the estimate, watch for unexplained drops, and lean on the data when you want to squeeze a little more value from the electricity your roof produces.
Frequently asked questions
Can I see how much electricity my solar panels are generating?
Yes. Your inverter records generation and usually reports it to an app or online portal, showing real-time output and totals by day, month and year. Many systems also show how much you use directly versus export. Some setups add per-panel monitoring so you can see each module's output.
What is a normal solar output, and when should I worry?
Output follows a strong seasonal pattern — much higher in summer than winter — so judge performance over a full year against your system's estimated annual generation, not a single day. A low winter reading is normal. Worry only about a persistent, unexplained shortfall that weather and season do not account for, and then contact your installer.
How do I know how much I'm exporting for SEG payments?
Your smart meter records the electricity you export to the grid, which is what your Smart Export Guarantee supplier pays you for. Many inverter apps also estimate export, but the meter reading is the figure that counts for payment. You can usually see export totals in your supplier's account alongside your SEG credits.
Sources & further reading
Figures on this page are typical UK ranges drawn from published sources and depend on your specific home. They are guidance, not a quotation or guaranteed saving.