Project development · Professional utility
Renewable Yield and P50/P90 Scenario Checker
Apply user-supplied aggregate uncertainty to a P50 yield and inspect an indicative P90 case.
Under an assumed normal distribution, P90 is P50 reduced by 1.28155 times aggregate uncertainty.
- Method
- v1.0
- Reviewed
- 2026-08-29
- Storage
- Session only
How the result was produced
- One-sided P90 factor: 1.28155 × 8%
- Applied to the user-supplied aggregate standard uncertainty.
Professional application
Use the result to frame the next decision.
- Sense-check consultant cases.
- Expose uncertainty sensitivity.
- Separate expected and confidence cases.
Worked case
Follow the units through one concrete example.
100,000 MWh P50 with 8% uncertainty gives about 89,748 MWh P90.
Exclusions
What this model deliberately leaves unresolved.
- Individual uncertainties are not combined here.
- Correlation is user-defined.
- This is not an independent yield assessment.
Decision questions
Interpret the result before you use it.
These are the questions most likely to expose a wrong unit, inconsistent boundary or misleading commercial shortcut.
Can this P50/P90 scenario check replace a bankable model?
No. It is an educational screening calculation. A financeable conclusion requires project-specific evidence, documented assumptions, expert review and due diligence.
Are my inputs stored or shared?
No. Scenarios remain in this browser session and are not persisted to a project database.
How should gross and net values be handled?
Choose one measurement boundary, label it and keep it consistent across inputs and comparisons.
What should accompany an exported result?
Keep the source, date, units, boundary, scenario and every assumption that materially changes the conclusion.
Methodology and evidence
Inspect the basis before relying on the output.
- Methodology version
- 1.0
- Reviewed
- 2026-08-29
- Data handling
- No inputs are persisted or transmitted to a project database.
- Boundary
- Educational screening model; not bankable engineering, legal, tax, financial or investment advice.
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