Solar Electricity
Solar Shading Loss Calculator
The purpose of Solar Shading Loss is to turn unshaded energy and shading loss into energy after shading. Keep the source condition with the saved result so later comparisons remain meaningful.
Set up the Solar Shading Loss case
Use measurements from one operating condition.
Formula used on this page
This page evaluates energy = baseline × (1 − shading loss). Its variables correspond to Unshaded energy and Shading loss.
For the example shown, energy after shading equals 20.64 kWh. Treat that value as a demonstration, not a recommendation.
Calculate energy after shading from unshaded energy and shading loss. For the companion azimuth-adjusted energy calculation, open Solar Azimuth Loss Calculator.
Input notes
Record module orientation, string configuration, and controller operating window. Write down whether each entry is measured, rated, assumed, or calculated.
Convert units once, retain the original reading, and verify the converted magnitude. Use Energy Efficiency Savings Calculator as the companion source for annual energy savings.
- Unshaded energy
- Default example: 24 kWh. Enter unshaded energy in kWh.
- Shading loss
- Default example: 14%. Enter shading loss in %.
Input quality checks
An unlabeled assumption can make an otherwise correct result unusable.
Recheck decimal placement and unit conversion when the answer looks unusual.
Where this estimate can fail
Electrical mismatch can make shading loss nonlinear.
A complete model can also include weather variability, mismatch, clipping, soiling, degradation, and curtailment. Use measurements, manufacturer data, or another calculation for effects that can change the decision.
Record module orientation, string configuration, and controller operating window.
A second scenario
Change Unshaded energy from 24 kWh to 28.799999999999997 kWh and preserve the rest of the case. This moves the answer from 20.64 kWh to 24.77 kWh.
This isolates one variable; a real system may change several at once.
A practical checking sequence
Check the source of unshaded energy before calculating. A credible result requires every field to describe the same physical condition and unit basis.
Use energy after shading alongside cold-voltage, hot-voltage, current, energy-yield, and controller limits. Preserve the unrounded number until all dependent calculations and comparisons are complete.
Document any effect handled outside this page, especially weather variability, mismatch, clipping, soiling, degradation, and curtailment. That note prevents a later reader from assuming the simple equation covered it.
Questions from practical use
What assumptions affect Energy after shading?
Electrical mismatch can make shading loss nonlinear. Also consider seasonal resource variation and controller or inverter operating windows.
What explains a gap between calculated and observed energy after shading?
Recheck units and operating state before investigating seasonal resource variation and controller or inverter operating windows.
How do I run a useful sensitivity check?
Keep unaffected entries fixed so the cause of the difference remains visible. Base energy estimates on the limiting season rather than an annual average alone.
Is the result a code-compliant design value?
No. Compare the value with a monthly or seasonal production case and apply relevant equipment and installation requirements.