Model/domain
Khalim Conn-Kowlessar e440e2df2e S0380.205: SAP 10.2 p.186 two-systems-different-parts MIT (weighted R + elsewhere blend)
When two main heating systems heat different parts of a dwelling, SAP
10.2 §7 (PDF p.186) adapts the mean-internal-temperature calculation:
- Table 9b weighted responsiveness: R = (1−(203))·R_sys1 + (203)·R_sys2.
- Rest-of-dwelling temperature (90)m = weighted average of T2 computed
  under EACH system's control schedule, weights (203)/[1−(91)] for sys2
  and [1−(203)−(91)]/[1−(91)] for sys1 (or sys2's control alone when
  (203) ≥ 1−(91)).

The cascade used Main 1's control + R=1.0 for the whole dwelling,
over-stating MIT by +0.037 °C on simulated case 6 (Main 1 radiators/2106
type 2 living + Main 2 underfloor/2110 type 3 elsewhere, R 1.0/0.75). That
inflated (97) heat loss by ~11 W → demand +61 kWh/yr.

`mean_internal_temperature_monthly` gains `main_2_control_type`,
`main_2_fraction`, `main_2_responsiveness`; cert_to_inputs derives them
from the second main detail (gated on main_heating_fraction > 0, so
single-main / DHW-only second mains pass the defaults → unchanged).
Case 6: (87) living, (90) elsewhere, (98c) demand 11991.96 and per-system
fuel (211)=7741.6458 / (213)=6995.3106 all match the worksheet to 1e-4.

Re-pin: golden 0240 (same 2106/2110 archetype, API-only) — PE +2.1519 →
+1.6893, CO2 +0.1051 → +0.0815 (both closer to zero; SAP 72 unchanged).
Single-main certs unchanged (2360 pass + 0 fail).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-03 16:02:56 +00:00
..
addresses standardist Address 2026-05-22 10:13:32 +00:00
data_transformation moved classifier data transformation to an easy one 2026-06-01 14:53:34 +00:00
epc Remove EPC and asset_list changes unrelated to SAL handler 2026-06-01 16:39:09 +00:00
fuel_rates feat(fuel-rates): FuelRates snapshot + repository foundation (ADR-0014) 2026-06-02 09:29:07 +00:00
geospatial feat(geospatial): GeospatialRepo — OS Open-UPRN coordinate lookup (#1131) 2026-06-01 16:28:48 +00:00
property feat(property): Property aggregate + PropertyRepository (#1132) 2026-06-01 16:28:48 +00:00
property_baseline refactor(baseline): Performance.from_sap_result replaces the loose mapper 2026-06-02 13:59:25 +00:00
sap10_calculator S0380.205: SAP 10.2 p.186 two-systems-different-parts MIT (weighted R + elsewhere blend) 2026-06-03 16:02:56 +00:00
sap10_ml Slice S0380.109: Solid brick + insulation via §5.7 Table 13 + §5.8 Table 14 (RdSAP 10) 2026-06-01 16:28:47 +00:00
tasks added postcode splitter rewrite to ddd 2026-05-19 16:35:09 +00:00
postcode.py get rid of comments 2026-05-20 13:21:11 +00:00