Millions of roofs are perfectly suited for solar energy but remain unused. Uncertainty about orientation, tilt, or shading holds many back. Our free tool provides clarity: In 2 minutes, we analyze your roof via satellite and show you how much electricity and money it holds.
Analyze Roof Potential NowThe true potential of your roof depends on the perfect interplay of these four factors. Our tool automatically evaluates all four for you.
The orientation determines when your roof gets the most sun. South provides the maximum annual yield. However, East-West roofs are ideal for self-consumption as they produce electricity in the morning and evening – exactly when you need it. Even north-facing roofs can be worthwhile with a low tilt.
The angle of your roof affects how directly the sun's rays hit it. For most of Europe, 30 to 35 degrees is considered optimal. But don't worry: deviations of up to 20 degrees up or down result in only minimal yield losses. Flat roofs are even ideal because the modules can be mounted at the perfect tilt and orientation.
How many modules fit on your roof? The important thing is the unobstructed area without dormers, chimneys, or skylights. Our tool helps you easily identify these areas. As a rule of thumb, even a free area of 20 m² can be enough to cover a significant portion of your electricity costs.
This is one of the most important factors. Trees, neighboring buildings, satellite dishes, or your own chimney can cast shadows on the modules and reduce the yield. PV Freund uses 3D building models to simulate the course of shadows throughout the day and year to create a realistic yield forecast.
With the integrated Shading Obstacle Tool, you can draw buildings and trees directly on the map. PV Freund then calculates for each of the 8,760 hours of the year whether your roof area is shaded – and shows you the actual yield reduction at the module level.
All 4 factors — orientation, tilt, usable area, and shading — simulated across 8,760 hours on a real roof.
Here's what your personalised analysis looks like
Do these widespread assumptions stand up to a fact check?
Myth 1: "Only pure south-facing roofs are worthwhile."
FALSE. East-west systems produce electricity more evenly throughout the day, which increases self-consumption without storage. Today, this is often more economical than the maximum yield of a south-facing roof at noon.
Myth 2: "My roof is too small."
OFTEN FALSE. Even a small system with 6-8 modules ("balcony power plant" on the roof) can cover your base load and reduce your electricity bill by several hundred euros per year. Every kilowatt-hour counts!
Myth 3: "A tree in the garden ruins everything."
NOT NECESSARILY. Temporary partial shading is now easily manageable. Technologies such as power optimizers or microinverters ensure that the entire system does not lose performance just because one module is in the shade. Learn more about smart storage and shading solutions →
Myth 4: "My roof is too old."
IT DEPENDS ON THE STATICS. It is not the age of the roof that is decisive, but its condition and statics. A PV system weighs only about 12-15 kg/m². Often, an installation is possible without any problems or can be combined with a planned roof renovation anyway.
Almost every roof type is worth analysing – but the potential varies significantly by shape. Here's what to expect from the most common roof geometries.
The most common roof type across Europe and an ideal solar platform. The two opposing slopes allow a classic south-facing layout for maximum annual yield, or an east-west split that covers morning and evening demand without needing battery storage. Most gable roofs fall within the optimal tilt range of 25–45°.
Four usable slopes means more flexibility – and more complexity. PV Freund analyses each slope independently and identifies which combination delivers the best economic return. Even a partly north-facing slope can contribute meaningfully when its tilt is low enough to limit reflection losses.
Arguably the best roof type for solar. Because there is no fixed structural slope, modules can be mounted at the ideal tilt and freely oriented. PV Freund scans 36 azimuths and 13 tilt angles to find the economically optimal layout – typically an east-west configuration that maximises self-consumption throughout the day, often without any battery storage required.
A single slope means solar potential is entirely direction-dependent. A south-facing shed roof with a 15–35° tilt is excellent. A north-facing one can still be worthwhile with a low pitch – and the exact numbers may surprise you. Run the free analysis to find out.
You don't need to cover your entire roof to cover a large share of your electricity costs. Here's a practical guide to matching roof area to real-world household demand.
The key insight: a well-oriented 20 m² roof is often more valuable than a poorly oriented 50 m² roof. PV Freund calculates area and orientation together – so you always see the true economic potential, not just a theoretical maximum. See exactly how much you can save on electricity costs →
Last updated:
