| Latitude | Tilt | Panel L | Mount H | Gap | Design | Pitch (output) |
|---|---|---|---|---|---|---|
| 31.5° | 25° | 2.10 m | 0.60 m | 0.50 m | Solstice noon | ≈ 4.1 m |
| 24.9° | 15° | 2.00 m | 0.50 m | 0.60 m | Solstice noon | ≈ 3.2 m |
| 35.0° | 30° | 2.30 m | 0.70 m | 0.50 m | Solstice noon | ≈ 5.1 m |
| 28.0° | 20° | 2.10 m | 0.80 m | 0.75 m | DOY 340, 11.0h | ≈ 4.6 m |
| 40.0° | 35° | 2.20 m | 0.60 m | 0.60 m | DOY 355, 12.0h | ≈ 6.0 m |
- Solar declination: δ = 23.45 × sin(360 × (284 + N) / 365)
- Solar elevation: α = asin( sinφ·sinδ + cosφ·cosδ·cosH )
- Hour angle: H = 15 × (t − 12)
- Row depth: D = L × cos(β)
- Top height: T = h + L × sin(β)
- Shadow length: S = T / tan(α)
- Required pitch: P = D + S + g
- GCR: GCR = D / P
Symbols: φ latitude, N day of year, t solar time, β tilt, L panel length, h mount height, g maintenance gap.
- Enter site latitude and your intended tilt angle.
- Add panel dimensions and mounting height at the front edge.
- Set a practical maintenance gap based on access needs.
- Use the winter solstice option for conservative spacing.
- Or select custom mode for a specific day and solar time.
- Press Submit to view pitch, rows fit, and layout metrics.
- Download CSV or PDF to share the results with teams.
For critical projects, validate spacing using detailed shading analysis and local codes.
Shading control and layout intent
Row spacing controls how much winter shade reaches the next row. This calculator uses a conservative solar position to estimate pitch, helping planners balance land use, access, and predictable output. Because spacing affects both energy yield and civil quantities, it should be checked early, then refined during detailed design. It supports early budgeting for grading, roads, and cable runs.
Solar elevation as a design driver
Solar elevation changes with latitude, season, and time of day. Lower elevation angles create longer shadows and demand larger pitches. Selecting winter solstice at solar noon often provides a practical worst case for fixed-tilt arrays. Custom day and time inputs support quick checks for commissioning, seasonal studies, or owner preferences. Solar time inputs reduce errors from time zones and daylight.
Geometry of the module row
The row depth equals panel length times cosine of tilt, while vertical rise equals panel length times sine of tilt. Adding mounting height gives the top edge height that casts the shadow. Increasing tilt or mounting height usually increases shadow length, so pitch grows. Maintenance gap adds clearance for safe cleaning, inspection, and drainage. Keep units consistent to avoid costly layout mistakes.
Interpreting pitch, GCR, and rows
Required pitch is the front-to-front row distance that avoids shading at the selected condition. Ground coverage ratio compares row depth to pitch and offers a quick density indicator. Higher GCR uses land efficiently but may increase shading risk and access constraints. The rows-fit estimate uses site length only; real projects also verify width, setbacks, and grading. Use row width outputs to plan aisles and routes clearly.
Construction checks before finalizing
Confirm the reference direction of site length, especially on irregular parcels. Validate that proposed pitches allow equipment turning radii, stormwater paths, and cable routing. If terrain is sloped, shadows vary by row; consider adding margin or using detailed shading tools. Exported results support coordination with structural, electrical, and civil teams. Record assumptions on drawings so crews set spacing.
FAQs
Q1. What pitch does the calculator report?
A: It reports front-edge to front-edge row spacing that avoids shading at the chosen sun condition, including the maintenance gap.
Q2. Why is winter solstice at noon recommended?
A: It usually produces long shadows and a conservative spacing baseline for fixed-tilt layouts, especially where winter performance is critical.
Q3. Does it account for sloped ground?
A: No. It assumes level ground. On slopes, adjust spacing or verify with a detailed shading study and site survey.
Q4. What is GCR and why does it matter?
A: GCR is row depth divided by pitch. It indicates layout density and helps compare land use against shading and access needs.
Q5. Can I use custom day and time?
A: Yes. Select custom mode, enter day-of-year and solar time, then compare the resulting pitch with your project constraints.
Q6. Are the CSV and PDF based on my latest run?
A: Yes. Exports use the most recent saved results in your session, so run the calculation before downloading.