Size.Solar

    Calculated solar panel tilt angle in Vienna

    We analysed solar production across a range of tilts (18° to 78°) to find the optimal settings for your location. The more frequently you adjust your panels, the greater the potential energy gain.

    1. Best fixed tilt

    36°

    Set it once for the entire year. The simplest approach.

    Method: Polynomial regression on annual production data.

    2. Two adjustments / year

    Winter: 41°

    Summer: 31°

    Provides a 0.1% gain over the best fixed tilt.

    Method: Decoupled regression on 6-month seasonal data.

    3. Four adjustments / year
    Summer18°
    Autumn51°
    Winter63°
    Spring31°

    Offers a 2.8% gain over the best fixed tilt.

    Method: Decoupled regression on 3-month seasonal data.

    4. Twelve adjustments / year
    Jan58°
    Feb60°
    Mar46°
    Apr31°
    May19°
    Jun18°
    Jul18°
    Aug28°
    Sep42°
    Oct55°
    Nov63°
    Dec71°

    Achieves the maximum 3.4% gain over the best fixed tilt.

    Method: Decoupled regression on monthly data for ultimate optimization.

    *Tilt angles are relative to horizontal. For Vienna, positive angles face South and negative angles face North. Gains are estimates based on modeling.

    Quote-ready tilt decision

    Give installers one fixed-angle target first

    Start the quote conversation with 36° South. Seasonal adjustment is only worth pricing if a supplier can show that roughly 2.8% extra production beats the cost, access risk, and warranty complexity of adjustable frames.

    Estimate productionStart roof design

    Base quote

    36° South

    Best default for normal roof-mounted systems and the first number to send to installers.

    Adjustable option

    Winter: 41° South

    Summer: 31° South

    Four seasonal changes model about 2.8% gain. Monthly adjustment models about 3.4%.

    Installer checks

    Roof pitch, available rail angles, wind loading, waterproofing, access for cleaning, and whether adjustment affects warranty.

    Direction check

    In Vienna, the practical target is a south-facing array. Shade-free roof space, inverter sizing, and battery goals usually matter more than small angle differences.

    Annual production by strategy

    Monthly performance breakdown

    Ready to design your full system?

    Use our comprehensive solar sizing calculator to design your entire system, including batteries and inverters, and get a detailed financial breakdown.

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