Phoenix 33.4° N
Year-round 33°, summer 18°, winter 48°. Snow not an issue — fix at 25° to balance summer peak load.
Solar panel tilt calculator
What's the optimal tilt angle for my solar panels?
Get the year-round optimal tilt (≈ latitude), summer tilt (latitude − 15°) and winter tilt (latitude + 15°), plus expected production gain from seasonal adjustment.
Panel Tilt & Azimuth
Solar panel tilt & azimuth optimizer
Year-round optimal tilt29.7°
Summer-optimized tilt20°
Winter-optimized tilt50°
Optimal azimuth180°
HemisphereNorthern (face south)
Results are first-pass estimates. Verify with installers, manufacturers, and utility tariffs before purchase.
How it works
How it works
- Year-round optimal tilt ≈ latitude — within 5% of true optimum for fixed-mount arrays.
- Summer tilt = latitude − 15°. Captures higher sun angle May–Aug for ~3–5% summer gain.
- Winter tilt = latitude + 15°. Reduces snow accumulation and improves Dec–Feb yield 10–25% in Zone 5+.
Worked examples
Worked examples
Boston 42.4° N
Year-round 42°, summer 27°, winter 57°. Two-position seasonal swap gains 6% annual.
Anchorage 61.2° N
Year-round 61°, winter 76°. Steep winter tilt sheds snow; near-vertical may capture albedo from snowpack.
Tilt angle FAQ
Tilt angle FAQ
What if my roof isn't at the optimal angle?
A 10° offset costs only 1–2% annual production. Most pitched roofs (15–35°) work fine for latitudes 30–45° N without tilt legs.
Does azimuth matter more than tilt?
Yes. Due south = 100%. West = 88%, east = 85%, north = 65%. Fix azimuth first, then worry about tilt.
Are tracking systems worth it?
Single-axis trackers gain 15–25%, dual-axis 30–35%. Add maintenance and cost: usually only pencils on ground-mount commercial sites.
How often should I swap seasonal tilts?
Twice a year (April and October) captures 90% of the benefit vs monthly adjustment.
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