Tilt & Orientation Yield Estimator
Get an indicative annual-yield figure for a roof from its direction and pitch, relative to an optimally-oriented array.
- Gives an indicative annual-yield figure for a roof from its direction and pitch.
- Compares your roof to an optimally-oriented array, expressed as a relative yield percentage.
- Adds a rating and guidance so you can read the result at a glance.
Indicative yield
99%
Rating
Excellent
Relative to an optimally-oriented array (north, ~latitude tilt = 100%). Indicative only — real yield depends on your exact location, shading and weather.
This gives an indicative annual yield relative to an optimally-oriented array (true north, tilt near your latitude = 100%). It multiplies two factors:
- Direction. In the southern hemisphere north is best; east- or west-facing roofs typically give up around 15%, and south-facing considerably more.
- Pitch. Output peaks near a tilt of roughly your latitude (about 20–30° for most of Australia). A dead-flat roof loses roughly 10%, and very steep pitches taper off too.
These factors are rules of thumb drawn from Australian orientation data — useful for a quick read, but real yield depends on your exact location, shading and weather. For precise numbers use a tool like NREL's PVWatts or ask your installer, and see our orientation field guide for the why behind the numbers. East/west splits also smooth output across the day, which can lift self-consumption even at a slightly lower total.
Estimates only — for guidance, not a quote or engineering specification. Nothing you enter is stored or sent anywhere; the maths runs entirely in your browser.
Frequently asked
- Is this tool free to use?
- Yes. The tilt and orientation estimator is free and needs no sign-up. It runs entirely in your browser.
- Is my data stored or sent anywhere?
- No. The tool runs in your browser and stores nothing. The figures you enter are not saved or sent anywhere.
- What does the relative yield percentage mean?
- It is an indicative comparison of your roof's direction and pitch against an optimally-oriented array. The figure is an estimate, not a measured output.
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