Bill / EnergyBreakdown / BillDerivation / sap_fuel were under
domain/property_baseline/ only because Baseline was built first. The Modelling
stage now needs them too, so move them (and their tests) to a neutral
domain/billing/ — Fuel/FuelRates already live in the shared domain/fuel_rates/.
Avoids a modelling -> property_baseline cross-stage import and a package name
that wrongly implies ownership (ADR-0011, ADR-0014 amendment). Pure git mv +
import rewrite across 10 files; 40 billing/baseline/repo tests pass, pyright
strict clean. CONTEXT.md Bill Derivation location updated.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The Rebaseliner is the assemble-and-score step (ADR-0013 amendment); its
SapResult is the scored picture that Bill Derivation also prices (ADR-0014),
so rebaseline() now returns a RebaselineResult{effective, reason, sap_result}
instead of (Performance, reason). CalculatorRebaseliner sets sap_result on
both branches (the bill prices it whether lodged or calculated figures win);
StubRebaseliner returns sap_result=None (runs no calculator). Orchestrator
unpacks the result; the bill wiring lands in the next slice.
Also refreshes the stale ML-era docstrings in rebaseliner.py to the
assemble-and-score model (the calculator, not ML, is the rebaseliner
mechanism per ADR-0013).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The SapResult -> EnergyBreakdown adapter (ADR-0014), a classmethod on the
target mirroring Performance.from_sap_result. Folds each positive per-end-use
delivered kWh into a billable EnergyLine: main/main-2/secondary heating and
hot water at their resolved fuel (sap_code_to_fuel); lighting/pumps-fans/
appliances/cooking/cooling as electricity. PV export carries to exported_kwh
for the SEG credit. Zero-kWh end uses emit no line; a positive kWh with no
fuel code raises rather than billing at a default (strict, mirrors the
calculator).
Adds BillSection.COOLING (electricity, from space_cooling_fuel_kwh_per_yr).
BillDerivation already prices any section it is given, so no change there.
Also corrects the ADR-0014 amendment: SapResult carries the calculator's own
fuel codes (raw API or Table-32 per mapper, ADR-0015); sap_fuel normalizes.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The fuel codes the calculator now puts on SapResult are its own codes — raw
gov-API enums or already-Table-32, depending on the source mapper (ADR-0015).
sap_code_to_fuel now runs the code through table_32.to_table_32_code
(promoted from private _to_table_32_code) — T32-first, then API-translate,
the SAME normalization the calculator's pricing/CO2 helpers use — before the
Table-32 -> Fuel dispatch, so the bill's carrier matches what the calculator
billed (incl. the API/T32 collision codes, e.g. 20 = wood-logs not heat-net).
Falls back to the raw code for billing fuels the price table omits (the 41-58
heat-network range), which resolve to HEAT_NETWORK -> UnpricedFuel — stricter
than, and intentionally divergent from, the calculator's lossy
default-to-mains-gas for an unpriced code (ADR-0014 §5).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
ADR-0014 BillDerivation attributes each end-use (HEATING / HOT_WATER /
SECONDARY / APPLIANCES / COOKING) to a fuel carrier and credits PV
export. SapResult already carried the per-end-use kWh but not WHICH
fuel each end-use burns, nor the annual exported kWh — so a downstream
SapResult->EnergyBreakdown adapter could not pick the right tariff.
Surfaces five output-only fields, threaded exactly like the recently
merged appliances/cooking change (2f039aeb):
main_heating_fuel_code RdSAP10 Table 32 / SAP 10.2 Table 12 fuel
main_2_heating_fuel_code code column (the lodged fuel code, e.g.
secondary_heating_fuel_code mains gas 26). None when the corresponding
hot_water_fuel_code system is absent / fuel not resolvable.
pv_exported_kwh_per_yr SAP 10.2 Appendix M1 §3-4 annual export kWh
(0.0 when no PV).
cert_to_inputs.py populates the four fuel codes from the existing
resolvers the cost/CO2 cascade already uses — `_main_fuel_code`,
`_secondary_fuel_code`, `_water_heating_fuel_code` (not reinvented);
Main 2 is the second `main_heating_details` entry, guarded for length.
There is a single CalculatorInputs construction site (cert_to_demand_
inputs delegates to cert_to_inputs). `pv_exported_kwh_per_yr` already
existed on CalculatorInputs; SapResult collapses its Optional to 0.0.
HARD CONSTRAINT honoured — output-only, zero rating drift. These fields
do NOT feed ECF / total_fuel_cost_gbp / co2_kg_per_yr / primary_energy_*
/ sap_score / any monthly value. Every golden-fixture, Elmhurst e2e
SapResult pin, section cascade pin, and heating-corpus residual stays
byte-identical: calculator suite 1658 -> 1661 passed (+3 new tests),
4 skipped, 0 failed before and after. pyright net-zero (51 -> 51 in
domain/; no new errors in the touched test files).
New tests: a synthetic threading test (four fuel codes + PV export pass
unchanged through calculate_sap_from_inputs; None PV collapses to 0.0)
and a cert-level pin (mains-gas combi cert 000516 -> main fuel code 26,
no Main 2, secondary 30, HW 26). Synthetic CalculatorInputs / SapResult
fixtures updated for the new SapResult fields (defaults cover Inputs).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
ADR-0014 BillDerivation prices a per-end-use EnergyBreakdown
(HEATING / HOT_WATER / LIGHTING / PUMPS_FANS / APPLIANCES / COOKING).
SapResult already carried the first four but not appliances or cooking,
so a downstream SapResult→EnergyBreakdown adapter had to stub those two
at 0 kWh — understating the bill by the whole unregulated electricity
load. Surface them so the property_baseline side can wire the sections.
Adds two output-only fields to CalculatorInputs + SapResult, threaded
exactly like lighting_kwh_per_yr:
appliances_kwh_per_yr — SAP 10.2 Appendix L L13/L14/L16a annual E_A
(sum of the §5 (68) monthly appliances kWh)
cooking_kwh_per_yr — SAP 10.2 Appendix L L20 (p.91) ELECTRICITY
estimate E_cook = 138 + 28×N
Both values already existed in cert_to_inputs.py (appliances_monthly_kwh,
cooking_monthly_kwh) — reused, not recomputed.
Fuel attribution: cooking_kwh_per_yr is the L20 ELECTRICITY figure (the
field docstring says so), distinct from the L18 cooking heat GAIN
(35 + 7N W) the §5 internal-gains cascade uses. The bill adapter should
treat cooking as an electricity carrier; a gas-cooker split, if ever
needed, is a separate follow-up.
HARD CONSTRAINT honoured — output-only, zero rating drift. Appliances +
cooking are unregulated and are NOT fed into ECF / total_fuel_cost /
CO2 / primary energy / sap_score. Every golden-fixture, Elmhurst e2e
SapResult pin, section cascade pin, and heating-corpus residual stays
byte-identical (1165 rated pins green). The synthetic CalculatorInputs
fixtures set the new fields non-zero on purpose so the existing cost/PE
reconciliation assertions act as leak detectors.
New focused test asserts both fields are populated (non-zero) and
threaded unchanged onto SapResult, with cooking equal to the L20
electricity figure (138 + 28×occupancy) to 1e-9. pyright net-zero
111 → 111.
Note: 11 pre-existing failures in test_appendix_u.py / test_table_32.py
arrived with the recently absorbed PR and are unrelated to this change
(they fail identically on the clean branch); flagged separately.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
PR feedback: prefer an abstract base the calculator inherits from over a
structural Protocol. Define `SapCalculator(ABC)` in the calculator package
(the engine owns its own contract) and have `Sap10Calculator` inherit it;
a future methodology is another subclass. Placing the ABC with the engine —
not in property_baseline — keeps the dependency pointing consumer -> engine
(sap10_calculator imports nothing from property_baseline). Consistent with
the repo's existing port convention (FuelRatesRepository(ABC)).
CalculatorRebaseliner keeps its reference to SapCalculator type-only (under
TYPE_CHECKING), so the module still does not import the calculator at
runtime. Test fakes now inherit the ABC since structural conformance no
longer applies.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 5a: the promotion. Replaces StubRebaseliner in production and collapses the
shadow runner into the rebaseliner (ADR-0013 amendment).
- CalculatorRebaseliner runs Sap10Calculator on every Property:
* sap_version < 10.2 -> Effective Performance IS the calculator output
(band via Epc.from_sap_score, CO2 kg->t, PEUI rounded), reason "pre_sap10".
* sap_version >= 10.2 -> Effective = lodged (API figures on-target), and the
calculator only logs divergence (SAP>0.5, PEUI/CO2 1%) as a validation signal.
* a calculator raise propagates -> batch aborts (ADR-0012); fix the cert at once.
- Rebaseliner.rebaseline gains property_id (for the divergence log).
- LoggingCalculatorShadow / the calculator_shadow seam removed from the
orchestrator; its divergence-comparison logic now lives in the rebaseliner.
- StubRebaseliner kept (signature updated) for orchestrator/repo unit tests.
The SapResult->EnergyBreakdown adapter + BillDerivation wiring (to populate the
bill block) follow once the appliances/cooking SapResult fields land.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 3 of Bill Derivation. sap_code_to_fuel(code) maps a SAP 10.2 / Table 32
fuel code to the canonical billing Fuel — bounded to the ~47 Table 32 codes (the
carrier, orthogonal to the PCDB product index, so all PCDB heat pumps share one
electricity code). Mains gas / LPG / oil+bioliquids / coal / smokeless / wood /
electricity (standard + off-peak) / heat-network groupings; an unmapped code
(dual fuel, grid-export) raises UnmappedSapCode rather than guessing.
Also: ADR-0014 deferred/TODO section records the stubbed appliances+cooking
(pending the SapResult fields), the off-peak day/night split, the heat-network
rate gap, and regional rates / ETL.
The SapResult -> EnergyBreakdown adapter (next slice) is gated on the
appliances/cooking fields landing on SapResult.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 2 of Bill Derivation. BillDerivation(fuel_rates).derive(breakdown) takes a
delivered-energy breakdown (per-section EnergyLine(section, fuel, kwh) +
exported_kwh) and produces a Bill: per-section kWh + cost, standing charges,
SEG credit, and total.
- Each end-use line billed at its fuel's unit rate.
- Standing charge added ONCE per distinct fuel used (a meter, not an end use);
off-gas fuels carry 0 so contribute nothing — no metered/unmetered special case.
- SEG export credit subtracted.
- Deterministic (ADR-0006); raises UnpricedFuel (via FuelRates) on an unpriced
fuel (e.g. heat network) rather than billing at a wrong default.
Pure domain — no calculator dependency; the SapResult->EnergyBreakdown adapter
is slice 3.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Wire Sap10Calculator into PropertyBaselineOrchestrator as a non-load-bearing
shadow runner. For each property it scores the Effective EPC beside the
load-bearing Lodged/Effective write, catches any strict-raise -> log.error
(never aborts the batch), and on success log.warning's divergence from Lodged:
SAP |continuous - lodged| > 0.5; PEUI/CO2 > 1% relative (CO2 after kg->tonnes).
Every line is tagged with sap_version so SAP-10.2 signal separates from
older-spec drift (ADR-0010 Validation Cohort).
Per ADR-0013, Calculated SAP10 Performance is not a persisted third value-set:
effective = calculated in every baselining scenario, so the calculator IS the
mechanism that produces Effective Performance (the Rebaseliner). It runs in
shadow only while being hardened; when overrides/estimation land it is promoted
to drive Effective and the failure posture flips to abort (ADR-0012, calculator
now load-bearing). No table change.
- ADR-0013 + CONTEXT (Calculated SAP10 Performance / Effective Performance /
Rebaselining) record the decision.
- CalculatorShadow port + LoggingCalculatorShadow + Calculator protocol.
- FakeCalculatorShadow for orchestrator unit tests.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
