Solar Tilt Orientation Sensitivity Chart

Compare tilt, orientation, shade, losses, and seasonal objective scenarios from NREL PVWatts or another documented model before a calculator result or selected production case is used in system sizing, ROI, emissions, or row-spacing work.

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Quick reference table

A solar tilt and orientation chart is a scenario comparison worksheet that compares baseline PVWatts kWh against alternate tilt and orientation rows, shade notes, loss assumptions, annual kWh, seasonal objective, and percent change without recommending one universal array angle.

Tilt and orientation sensitivity worksheet

Tilt and orientation sensitivity worksheet
Scenario field	Record on worksheet	Follow-up
Baseline case	PVWatts run, annual kWh, tilt, orientation, date retrieved	Confirm the baseline matches the project address and production basis
Tilt case	Candidate tilt, annual kWh, seasonal objective	Check roof/rack practicality and row-spacing effects
Orientation case	Candidate orientation, annual kWh, morning or afternoon bias	Review load shape, export value, and project objective
Loss and shade case	Shade note, loss percentage, annual kWh delta	Request shade model, layout revision, or project review

Scenario comparison record

Scenario comparison record
Comparison	Worksheet value	Boundary
Annual energy	Baseline kWh, scenario kWh, percent change	Annual kWh alone does not decide the project
Seasonal objective	Winter, summer, shoulder season, or annual basis	A seasonal objective can favor a different geometry than annual energy
Financial review	Selected production case for ROI and export value	Keep scenario assumptions visible before payback review
Design review	Selected tilt, orientation, shade, and row-spacing notes	Verify equipment, roof, racking, utility, and project constraints

When to use the solar sizing calculator

When to use the solar sizing calculator
Use case	Open the calculator when	Keep on this chart
Best tilt or azimuth question	You need a scenario kWh comparison instead of a generic angle	Baseline case, date retrieved, and rejected scenarios
East-west-south roof comparison	Each roof plane has tilt, orientation, loss, and shade assumptions ready	Scenario labels and project objective
Ground-mount seasonal objective	Winter, summer, or annual production goals need kWh deltas	Seasonal objective and row-spacing note
ROI production case selection	One scenario must feed payback, emissions, or battery analysis	Selected case, reason, and model limits

Formula basis

Scenario delta = scenario annual kWh - baseline annual kWh. Scenario percent change = scenario delta / baseline annual kWh x 100.

Baseline annual kWh is the reference PVWatts or model result selected for comparison.
Scenario annual kWh is the result for a different tilt, orientation, shade, losses, or seasonal objective.
Tilt records the array angle from horizontal for the scenario.
Orientation records the compass direction of the array for the scenario.
Shade and losses record the modeled assumptions that changed the production result.
Seasonal objective records whether the scenario is annual energy, winter support, summer output, roof fit, or row-spacing driven.

Worked examples

Roof orientation sensitivity recordCompare south, east, and west roof planes with the same PVWatts date retrieved, tilt, losses, annual kWh, seasonal objective, and ROI review note.

Ground-mount tilt scenario recordDocument baseline tilt, candidate tilt, row-spacing note, shade assumption, annual kWh delta, seasonal objective, and review notes before choosing the production case.

Assumptions. Balanced load and line-to-line voltage assumptions behind this chart.

The worksheet is a scenario comparison and does not guarantee output, utility approval, structural approval, or financial performance.
No universal tilt or orientation is recommended by default; the selected case depends on site geometry, shade, seasonal objective, utility rate, and project goals.
PVWatts or model scenarios should keep date retrieved, weather dataset, tilt, orientation, array type, losses, and shade assumptions visible.
Scenario comparison should be reviewed before the selected production value feeds ROI, emissions, battery, or system-sizing worksheets.

Code and standard notes. Planning limits that should be checked before final equipment selection.

Use this chart as a scenario comparison record; verify NREL PVWatts inputs, date retrieved, weather dataset, tilt, orientation, array type, shade model, losses, row-spacing implications, roof or racking constraints, utility requirements, project model, and project objective before using a scenario result.

How to use this chart

1Set a baseline caseRecord the PVWatts or model run used as the baseline, including date retrieved, weather dataset, tilt, orientation, losses, and annual kWh.

2Compare scenario changesChange one or two visible assumptions such as tilt, orientation, shade, losses, or seasonal objective and record the kWh delta.

3Route the selected caseCarry the selected production case into system sizing, ROI, emissions, or row-spacing review with the rejected scenarios still visible.

Worksheet checklist. Record source basis, review gaps, and assumptions before using the chart result.

Capture baselineWrite location, date retrieved, PVWatts or model file, tilt, orientation, losses, shade, and annual kWh.
Capture sensitivity rowsRecord tilt changes, orientation changes, shade changes, loss changes, seasonal objective, scenario kWh, and percent change.
Capture selected caseDocument selected case, reason, rejected cases, model limitations, and review notes.

Common mistakes to avoid. Review these before turning chart current into an equipment decision.

Treating a single array angle as universal without checking site geometry and project objective.
Comparing tilt or orientation while changing shade, losses, or dataset assumptions without labeling the change.
Moving a production value into ROI without recording the scenario comparison behind it.

Frequently asked questions

These answers explain how to use the chart without turning a quick reference into a final design decision.

Does one tilt or azimuth work for every solar project?

No. Tilt and orientation choices depend on site geometry, shade, roof or racking constraints, seasonal objective, utility rate design, project load shape, and equipment layout.

Why compare scenarios before ROI?

ROI, export value, emissions, and battery sizing depend on production assumptions. A scenario comparison keeps the selected production case and alternatives visible before those values move into finance or design review.

When should I open the solar sizing calculator from this chart?

Open the calculator when each candidate tilt or azimuth has a date retrieved, shade note, losses, seasonal objective, and baseline kWh ready for a scenario comparison.