Check your electricity tariff
At 32 ct/kWh a tariff check is worth it. At 26 ct/kWh you save
€140 per year
on the 2,334 kWh you still buy from the grid after the solar system has covered its share.
Your system
Solar array power
2,000 Wp is a common legal maximum for plug-in systems, for example in Germany.
Inverter output limit
Battery capacity
Location and mounting
Mounting and orientation
Your household
Household
Prices
Currency
Typical price for this hardware: €349
Plug-in rules differ by country. The defaults follow common European limits, such as those in Germany: up to 800 W inverter output and 2,000 Wp of panels. Exported power is assumed to earn nothing. Check your local rules.
Your result
Pays for itself after 1.6 years, then saves €213 every year.
Payback time
1.6years
Selected setup: 1.6Scale in years, shaded: the first 10 years
A 1.6 kWh battery would save another 103 kWh/year (+€33), but extends the payback by 2.4 years.
Annual bill reduction
€213per year
€17.77 per month
10-year net return
+€1,783
after subtracting €349 purchase price
Matching kit
800 Wp without battery
2 panels of 400 Wp · 800 W micro-inverter
Typical price €349
Where the solar energy goes
- 85 %Used directly666 kWh
- 0 %Used via battery0 kWh
- 15 %Given to the grid for free118 kWh
Battery losses (about 10%) are already deducted.
Cumulative cash flow in €, starting at −€349
- Selected setup
- With 1.6 kWh (comparison)
* Partner link. If you buy or sign a contract we may earn a commission. Your price stays the same.
Assumptions and limits
Model with 980 kWh/kWp annual yield (south-facing, central Europe around 51° N), constant electricity price, no degradation and no feed-in payment. Direct use is driven by base load; the battery runs at 90% efficiency and at most 210 full cycles a year. Real results depend on location, shading and consumption.
Getting started
Your next steps
A short checklist from the first idea to a running system. The search buttons open Google with a matching query for your country.
Check for funding before you buy
Some regions and cities pay a grant for plug-in solar, but usually only if you apply before buying. Keep the receipt.
Search on GoogleCheck the rules where you live
Tell your landlord or owners' association first. They can only refuse for good reasons, but they may have a say in how it is mounted.
Search on GooglePick a kit that fits
Compare panel output, the inverter limit, the mounting and the warranty. A battery only pays off if you use little power while the sun shines.
Register it
Enter the system in the Marktstammdatenregister within one month. You no longer need to tell the grid operator separately.
Search on GoogleTrack the real payback
Once it runs, log your meter readings in TrackIt+ to see whether the system keeps its promise and when it has paid for itself.
Get TrackIt+
Android app
TrackIt+
Track your real payback and your whole household
TrackIt+ for Android goes far beyond solar. Log your meters, your PV system, your cars and your finances in one app, see yearly cost and savings forecasts and get a heads-up before contracts end. It works offline, needs no account and is free to start.
- Electricity, gas, water and heating meters
- Solar generation, feed-in, self-use and payback progress
- Cars, hybrids and EVs with mileage, fuel and charging costs
- Savings plans, loans, insurance and fixed costs
- Free for up to 10 trackers. PRO is a one-time purchase, no subscription
FAQ
Guide and FAQ
How does payback differ between plug-in and rooftop solar?
A plug-in system costs a few hundred euros and mostly offsets your daytime base load, so it often pays back within a few years. A rooftop system costs thousands of euros and relies on feed-in payments for much of its income, so around ten years is common in this model. In many countries plug-in systems earn nothing for exported power, while rooftop systems receive a feed-in tariff. Both modes use the same payback ruler so you can compare them.
When does a solar battery pay off?
A battery pays off when the extra kWh it shifts into the evening are worth more than its price. With a cheap plug-in kit it usually delays payback, because the panels already cover most of the daytime load. It helps with a larger array, a high electricity price, a big evening load, or when midday peaks would otherwise be clipped or exported for nothing. Compare the setup with and without a battery in the calculator.
How do heat pumps and EVs boost self-consumption?
Both add consumption that you can shift into sunny hours: charge the car at midday or run the heat pump while the sun shines. More daytime consumption means more solar kWh replace grid power at your electricity price instead of being exported at a feed-in rate of around 7 ct/kWh. Switch on the heat pump or EV toggle in rooftop mode to see the effect. Winter heating still needs grid power, because solar yield is lowest then.
Why does tracking your real meter readings matter?
Every payback figure is a model. Your actual yield, shading and consumption decide the real result. Reading your meters on the same day each month shows how much solar power you use directly, how much you export and how your bill changes. TrackIt+ for Android logs your meter readings offline, and its PV cockpit shows how far your system has really paid for itself, so you can compare reality with this calculator.
What else can the TrackIt+ app do?
TrackIt+ is a household tracker for Android, not just a solar log. Besides your PV system it tracks electricity, gas, water and heating meters, cars, hybrids and EVs with mileage, fuel and charging costs, and finances such as savings plans, loans, income, fixed costs and insurance, with a reminder before a contract ends. Forecasts show your expected yearly costs and savings. The free version covers up to 10 trackers with the current and previous year, automatic local backups and a fingerprint lock, all offline and without an account. PRO is a one-time purchase with no subscription and adds unlimited trackers, your full history, the PV cockpit with payback tracking, household sync via Google Drive, family profiles and reading reminders.