Solar PV Calculator
Costs, yield and payback – with the EEG tariffs from August 2026
Solar PV in 2026: what has paid off and what has not
The profitability of a solar system comes down to a single number: self-consumption. A kilowatt-hour you use yourself is worth around 35 cents, because it replaces one you would have bought. The same kilowatt-hour fed into the grid earns 7.70 cents – about a fifth. A household that is at home during the day, or runs a heat pump or wallbox (an EV home charger), therefore ends up with completely different payback times from one that mainly needs its power in the evening.
The feed-in tariffs from August 2026
For systems commissioned from 1 August 2026, the Federal Network Agency (Bundesnetzagentur) lists the following rates (table currently valid until 31 December 2026). The 1.5 ct/kWh increase for systems of 40 kWp and above envisaged in the Solarpaket I (the 2024 solar legislation package) is not yet in effect because the EU has not approved it.
| Capacity band | Surplus feed-in | Full feed-in |
|---|---|---|
| up to 10 kWp | 7.70 ct/kWh | 12.22 ct/kWh |
| over 10 to 40 kWp | 6.66 ct/kWh | 10.24 ct/kWh |
| over 40 to 100 kWp | 5.44 ct/kWh | 10.24 ct/kWh |
The tiering matters: each rate applies only to the capacity within its band. A 20 kWp system receives 7.70 cents for the first 10 kWp and only 6.66 cents for the second 10 kWp – the calculator shows this as a weighted blended rate. The rates fall by one per cent every six months as scheduled; the current approval expires at the end of 2026.
Purchase costs fall with system size
The Verbraucherzentrale (German consumer advice centre) regularly analyses real quotes. The most striking finding is the degression: a small 5 kWp system costs around €2,090 per kWp, while from 16 kWp it is only €1,010. The reason is mundane – scaffolding, travel, planning and registration are needed regardless of how many modules go up. If you have the roof space, it is better to cover it fully than to size the system tightly.
Since 1 January 2023 no VAT has been charged on the purchase and installation. The prices given are therefore final prices, not net prices.
The Solarspitzengesetz slows down new systems
Since 25 February 2025: for new systems there is no payment for hours with a negative wholesale electricity price. The money is not lost – the support period is extended by exactly those hours. The second rule is more noticeable: anyone who does not have a smart metering device installed must permanently limit feed-in to 60 per cent of the system's output. For a well-utilised south-facing system that costs yield; for an east-west system with a flatter midday peak it hardly does.
Storage: expensive, but effective
A battery storage unit lifts the self-consumption rate from a typical 30 per cent to 60–70 per cent. That is a lot – but at 8 to 10 kWh of capacity it costs around €3,840 to €4,100. Whether that pays off depends on the electricity price: the more expensive grid power is, the sooner storage pays for itself. Try both variants in the calculator by setting the storage size to 0.
Sources
- Feed-in tariff: Bundesnetzagentur (Federal Network Agency), support rates for commissioning from 1 August 2026
- System and storage prices: Verbraucherzentrale, as of 28 August 2026
- VAT and the Solarspitzengesetz: Verbraucherzentrale, as of 1 August 2026
Frequently asked questions about solar PV
In its analysis of 28 August 2026 the Verbraucherzentrale (the German consumer advice centre) gives tiered average prices: €2,090 per kWp for 4–6 kWp, €1,410 per kWp for 9–10 kWp and €1,010 per kWp from 16 kWp. (kWp, kilowatt-peak, is the rated output of the panels.) A 10 kWp system therefore costs around €14,000. The price per kWp falls markedly with system size – scaffolding, travel and planning are only incurred once. A battery storage unit costs an extra €360 to €510 per kWh.
For systems commissioned from 1 August 2026 (according to the Federal Network Agency the rates currently apply until 31 December 2026, because the EU approval of the EEG, Germany's Renewable Energy Sources Act, expires at the end of the year), the grid operator pays 7.70 cents per kWh for surplus feed-in on the portion up to 10 kWp, 6.66 cents up to 40 kWp and 5.44 cents up to 100 kWp. For full feed-in the rates are 12.22 and 10.24 cents respectively. The rate is fixed at commissioning and then applies for 20 years plus the year of commissioning.
That depends almost entirely on self-consumption. Every kilowatt-hour you use yourself saves the full electricity price of around 35 cents, while every kilowatt-hour fed in earns only 7.70 cents – a little over a fifth. Anyone who uses a lot of power during the day is typically in profit after 10 to 14 years. The calculator works out the point in time from your inputs, taking module ageing, running costs and electricity price rises into account.
On paper, storage is almost always the least economical component of a system: it lifts the self-consumption rate from about 30 to 60–70 per cent, but quickly costs €4,000 or more. Whether it pays off depends on the electricity price and the storage size – as a rule of thumb, 1 kWh of storage per 1,000 kWh of annual consumption. Set the storage to 0 kWh in the calculator once and compare the payback period.
Since 1 January 2023 no VAT has been charged on the purchase and installation – the Verbraucherzentrale puts it this way: a VAT rate of 0 per cent applies to the private purchase of a photovoltaic system. Income from feed-in and self-consumption is also exempt from income tax for systems on single-family homes up to 30 kWp. The prices shown in the calculator are therefore final prices.
For systems commissioned since 25 February 2025, the feed-in tariff is not paid during hours with a negative wholesale electricity price. In return, the support period is extended by exactly those hours, so the payment is not lost but shifted to later. Anyone who does not install a smart metering device must permanently limit feed-in to 60 per cent of the system's output – depending on the system, that costs a few per cent of yield.
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