Assessing a north-facing roof
Are solar panels on a north-facing roof worthwhile?
Yes, a north-facing roof can be worthwhile, but not every one. What matters are the roof pitch, location, shading and the costs in the specific quote. A shallow north-facing roof has to be assessed differently from a steep one. Our calculator estimates the electricity yield, not your return.
Yield first, then economics: check the north side on its own first. For an extension, what counts are its additional costs and its additional benefit, not simply the average of the whole south-north system.
How much electricity does a north-facing roof deliver by comparison?
Same location (Berlin), same weather data, 10 kWp in total per variant. Compare north and south at the same pitch in each case. The percentages, by contrast, all refer to South 35°. These are model values, not measurements from an existing system.
| Roof | kWh/year | Share of South 35° | Compare |
|---|---|---|---|
| South 10° | 9,028 | 92% | Open in calculator: South 10° |
| South 35° | 9,853 | 100% | Open in calculator: South 35° |
| South 60° | 9,332 | 95% | Open in calculator: South 60° |
| North 10° | 7,481 | 76% | Open in calculator: North 10° |
| North 35° | 5,252 | 53% | Open in calculator: North 35° |
| North 60° | 3,561 | 36% | Open in calculator: North 60° |
| East + West 35° | 7,788 | 79% | Open in calculator: East + West 35° |
Monthly yield: south, north and east-west at 35°
| Month | South 35° | North 35° | East + West 35° |
|---|---|---|---|
| Jan | 264 | 108 | 160 |
| Feb | 526 | 104 | 286 |
| Mar | 759 | 346 | 589 |
| Apr | 1,154 | 499 | 891 |
| May | 1,136 | 969 | 1,100 |
| Jun | 1,278 | 1,052 | 1,209 |
| Jul | 1,286 | 896 | 1,146 |
| Aug | 1,214 | 622 | 982 |
| Sep | 967 | 298 | 699 |
| Oct | 646 | 213 | 424 |
| Nov | 397 | 68 | 181 |
| Dec | 225 | 77 | 121 |
Data as of 2026-09-28. Berlin (52.52° N, 13.405° E), PVGIS 5.3 / SARAH3 (EU JRC), typical meteorological year; monthly irradiance scaled with DWD DUETT (1991-2020) (© Deutscher Wetterdienst, Germany's national weather service, CC BY 4.0; processed by us). Calculated with our solar model, not with PVGIS PVcalc: 14% configured system loss, additional model-internal temperature and reflection losses, no additional local shading, no inverter limit. East-west: 5 + 5 kWp; otherwise only one roof side with 10 kWp. Rounded values; not a weather forecast. The live calculator loads current weather data, so later results may differ.
Why does the roof pitch make so much difference?
A north-facing roof also receives diffuse sky radiation. At a shallow pitch, its orientation differs less from a horizontal surface. In Germany, a steep north-facing surface receives considerably less direct sun, especially in winter. Additional shade from trees, dormers or neighbouring buildings can make the result worse still.
That is why there is no reliable blanket rule such as “north always delivers 70% of south”. The comparison of roof pitch and orientation shows the dependency at a fixed location.
When is the north side economically interesting?
- The additional installation is inexpensive, for example because scaffolding and electrical work are needed anyway. Whether the inverter and grid connection have spare capacity must be checked by the installer.
- Part of the additional electricity replaces grid electricity at the time it is generated. A high annual consumption alone does not prove high self-consumption.
- There is little local shading and a suitable roof surface. Roof condition, structural capacity and any necessary renovation belong in the review of the quote.
A simple calculation, explicitly not a return forecast
Annual gross benefit ≈ additional self-consumed kWh × avoided electricity price + additional kWh fed into the grid × feed-in tariff.
Freely chosen example, not taken from the table: 6,000 additional kWh/year, 20% of it self-consumed, €0.30/kWh of avoided grid electricity and €0.08/kWh feed-in payment give €360 + €384 = €744 per year. With assumed additional investment costs of €8,000, this works out at around 10.8 years of simple payback.
This ignores operating costs, financing, degradation, repairs, taxes and spare parts. The 8 cents are an assumption for the calculation, not a statement about the current EEG rate (the German feed-in tariff under the Renewable Energy Sources Act, Erneuerbare-Energien-Gesetz). Use your quote, your tariff and the feed-in tariff that applies to your system. For an extension, the additional self-consumption may be lower because the south side already covers demand. Battery storage does not increase the benefit for free.
How to check your own north-facing roof
- Open a north variant above and set your location in the calculator.
- Enter the real pitch and the planned kWp. In the calculator, north is 0°; side B stays switched off for the single comparison.
- Check the annual and monthly curves, not just a sunny summer day. Fallback weather data are only a simplified estimate.
- Have shading, roof condition, inverter and additional costs checked by an installer.
What the calculator cannot answer
No detailed 3D shading, no individual optimisation of self-consumption or battery storage, no financing calculation and no yield guarantee. Brand-neutral means: the calculation does not recommend any particular manufacturer. Read the model limits before you make an investment decision.
Sources and context
Weather data: EU JRC PVGIS. Model and data processing: our methodology. Binding feed-in tariff rates: Bundesnetzagentur on EEG funding (Germany's Federal Network Agency, page in German).