Note: Figures and details may be anonymised for data-protection reasons; the methodology reflects real projects.
750 kWpSystem capacity
≈ 30%Shortfall vs. forecast
Existing systemFault developed during operation
ResultTechnical root cause identified
Background
A system operator reported persistently low yields compared to forecast and expected values. Monitoring showed deviations but no clear cause. The objective was a substantiated assessment including root-cause analysis and a remedial action plan.
Key Questions
- Is the yield shortfall technically justified and quantifiable?
- Which components/strings are affected?
- Which measures will achieve a lasting improvement in yield?
Approach
- Data review: Yield data, weather correlation, plausibility, comparison periods.
- String/layout check: Wiring, string lengths, MPP ranges, planning documents.
- On-site inspection: Visual check, documentation, as-built vs. as-planned comparison.
- Measurements: Electrical testing (string-specific) and verification of anomalies.
- Assessment: Root-cause analysis, yield impact, remedial action and prioritisation.
Results
The analysis revealed a combination of causes: faulty string layout and areas with deviating performance, causing individual strings to operate outside their optimal working range. The deviation was reproducible and the yield impact was quantifiable.
Outcome: Technical root cause clearly documented, yield shortfall quantified, remedial action plan drawn up (e.g. corrections to wiring, component verification and optimisation depending on findings).
Value for the Client
- Substantiated basis for decisions (warranty / insurance / installer)
- Clear technical argument instead of assumptions
- Concrete prioritised measures with expected impact
Request a free initial assessment – Email: info@gutachterpv.org