Model/tests
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
..
applications put db engine construction inside handler to avoid import errors in test 2026-06-09 15:18:42 +00:00
datatypes fix(mapper): map truncated Elmhurst glazing label "Double between 2002" (RdSAP 10 Table 24 code 3) 2026-06-21 06:15:25 +00:00
domain fix(water-heating): split whc-903 immersion HW CO2/PE on off-peak tariffs 2026-06-24 09:05:21 +00:00
e2e Prove prediction resolves landlord overrides to a real cohort match end-to-end 🟩 2026-06-16 15:20:49 +00:00
fixtures/epc_prediction feat(epc-prediction): geo-proximity weighting, per-component (#1227) 2026-06-15 14:58:42 +00:00
harness feat(modelling): drive measure scoping from the Scenario's exclusions 2026-06-16 15:26:25 +00:00
infrastructure fix(water-heating): derive combi keep-hot from the PCDB record, default no-keep-hot 2026-06-23 21:22:02 +00:00
magic_plan Migrate all MagicPlan tests to single new-format fixture 🟪 2026-06-05 12:59:56 +00:00
orchestration feat(modelling): mark a Property as run via has_recommendations + updated_at 2026-06-16 23:34:33 +00:00
repositories Overlay landlord property-type and built-form corrections onto the Effective EPC 🟩 2026-06-17 18:06:29 +00:00
scripts fix terraform error and pass handler bool for dry runs 2026-06-15 14:06:54 +00:00
utilities added floats helper 2026-06-12 14:28:41 +00:00
__init__.py added postcode splitter rewrite to ddd 2026-05-19 16:35:09 +00:00
conftest.py Audit generator populates XLSX, uploads to S3, and records UploadedFile row 🟪 2026-06-09 12:05:55 +00:00
test_lambda_packaging.py better smoke tests to check what is failign 2026-06-17 11:53:33 +00:00