CALC-065

Discount rate as a mechanical lever, and the direction it runs

Feeds CLM-0380 and CLM-0523. SHARED - two claims, one section. Answers QST-004. Basis: dimensionless CRF ratios.

Script. restate-lcoe.py SECTION 7, section_decomposition() sub-heading (b), emitted at line 692. Note the locator: CLM-0380's `src` says Section 4(b) and its `support` says Section 7(b). The `support` field is right.

Why it was needed. Discount rate was the leading candidate explanation for the spread before the exercise ran - it is the largest single lever in most LCOE comparisons. Establishing its size was necessary; establishing its direction is what actually settled the question.

Inputs.

All four inputs are STATED by their sources. There is no assumed parameter in this record, which is why it carries a mechanism finding at MED confidence on arithmetic alone.

Working, transcribed.

CRF( 2 per cent, 30 yr)  =  0.04465
CRF( 3 per cent, 30 yr)  =  0.05102
CRF(10 per cent, 30 yr)  =  0.10608
CRF(20 per cent, 30 yr)  =  0.20085

CRF(20%,30yr) / CRF(2%,30yr)  =  4.5 x
CRF(20%,30yr) / CRF(3%,30yr)  =  3.9 x

Result: 3.9x to 4.5x, the largest single mechanical lever measured in isolation in this corpus.

Conclusion, and the direction is the entire finding. The study with the lowest raw LCOE (Frazer-Nash) carries the highest discount rate, 20 per cent. The study with the highest raw LCOE (NASA) carries the lowest, 3 per cent. Equalising the rate therefore moves the two apart, not together. A 4x lever pointed the wrong way does not explain a 20x gap; it deepens it. This is the quantitative confirmation of what CLM-0360's notes had already recorded qualitatively.

Where this fails. A description of the pattern in this corpus's two institutional anchors. It is not a general claim that discount rate never explains cost differences between studies - only that it does not explain this one. CLM-0380's own limits field says exactly that and it should travel with the record.

Why CLM-0523 needs no separate record. Its support field reads, in full, "Reproduced from CLM-0380 in full." Same CRF values, same 3.9-4.5x, same direction argument. It exists to serve a different document's Pillar 4 and adds no arithmetic. Drafting a second record would be drafting the same four CRF values twice.

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