Model/tests/domain/sap10_calculator
Khalim Conn-Kowlessar 39ae2cf0c2 fix(water-heating): split whc-903 immersion HW CO2/PE on off-peak tariffs
SAP 10.2 Table 12d/12e: electric water heating on a 7-/10-hour tariff bills
CO2/PE at the high-rate code (32/34) and low-rate code (31/33), kWh-weighted
by the Table 13 high-rate fraction. The cost path already applied this split;
the CO2/PE factors did not — they used the flat annual Table 12 figure
(0.136 CO2 / 1.501 PE) for ALL dual-rate electric HW.

That flat-annual behaviour (slice S0380.163) was validated only against
HW-from-main "low-rate cost" certs (100% low, no high-rate split). It is NOT
how Elmhurst bills a whc-903 ELECTRIC IMMERSION: the hand-built case-50
worksheet (000565 + dual immersion, 7-hour) splits HW CO2/PE into "high rate
cost" (CO2 0.1475 / PE 1.5514) + "low rate cost" (CO2 0.1238 / PE 1.4429)
weighted by the Table 13 fraction 0.1009. So flat-0.136 for immersion HW was
a spec gap on our side, not an Elmhurst divergence.

Fix: `_electric_immersion_hw_high_rate_fraction` threads the Table 13 fraction
(scoped to whc-903, 7-/10-hour, cylinder data present) into the HW CO2 + PE
factor helpers, which then blend the Table 12d/12e high/low codes. The flat
rule is unchanged for HW-from-main and 18-/24-hour (no Table 12d split), so
the S0380.163 41-variant cases and the existing pin are untouched.

Case 50: rating CO2 2413.48 -> 2397.1237 = Elmhurst EXACT; demand CO2 2007.1384
EXACT; demand PE +111 -> +32.5 residual (within corpus PE noise). Corpus
unchanged 73.3% / MAE 0.774 / CO2 0.08 / PE 3.4 (62 whc-903 off-peak certs;
aggregate gauges hold). SAP unaffected (cost-based).

Pin: test_whc903_immersion_hw_co2_pe_factors_split_high_low_on_off_peak; doc
updated in SAP_CALCULATOR.md §8.1.
pyright strict gate not run locally (pyright not installed in this container).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-24 09:05:21 +00:00
..
climate Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
rdsap fix(water-heating): split whc-903 immersion HW CO2/PE on off-peak tariffs 2026-06-24 09:05:21 +00:00
validation Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
worksheet test(worksheet): pin simulated case 52 — regular gas boiler + cylinder 2026-06-24 08:50:19 +00:00
__init__.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_bre_worked_examples.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_calculator.py fix(rating): floor the continuous SAP score at 1 (SAP 10.2 §13 / RdSAP 10 §13) 2026-06-19 14:03:13 +00:00
test_pcdb_etl.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_pcdb_lookup.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_pcdb_table_322_lookup.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_pcdb_table_323_lookup.py feat(pcdb): parse Table 323 (Centralised MEV / MVHR) + Table 329 efficiency IUF 2026-06-23 19:29:17 +00:00
test_pcdb_table_329_lookup.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_pcdb_table_362_lookup.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_postcode_weather.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_real_cert_sap_accuracy.py Pin uprn_10093116336 (full-SAP gas-combi 2-storey semi): engine 83 vs Elmhurst 79 2026-06-17 09:41:29 +00:00
test_table_12.py Move sap10_calculator tests to tests/domain/sap10_calculator/ for CI 2026-06-02 16:58:00 +00:00
test_table_12a.py feat(tariff): complete §12 Unknown-meter clause — GSHP/WSHP main triggers off-peak (RdSAP 10 PDF p.62) 2026-06-23 10:09:59 +00:00
test_table_13.py fix(water-heating): 18-/24-hour immersion DHW bills 100% low-rate (Table 12a scope) 2026-06-10 22:01:35 +00:00
test_table_32.py fix(fuel): raise UnpricedFuelCode for unrecognised fuels instead of silently defaulting to mains gas 2026-06-23 08:31:04 +00:00