Model/domain
Khalim Conn-Kowlessar 2e5c519861 Slice 102e: heat-pump APM efficiencies via SAP 10.2 Appendix N3.6 / N3.7(a)
For any cert lodging a Table 362 heat-pump PCDB record, the cascade now
replaces the Table 4a category defaults with PSR-interpolated
efficiencies per SAP 10.2 Appendix N (PDF p.108):

  (206) = 0.95 × η_space,1_interp                  (N3.6 in-use factor)
  (217) = in_use_factor × η_water,3_interp         (N3.7(a) + footnote 49)

where η_space,1 and η_water,3 are PSR-dependent values from the PCDB
record's PSR-group table (decoded in slice 102c.2), and the dwelling's
PSR is computed per PDF p.100 line 5946-5950:

  PSR = max_nominal_output_kw / (HLC_annual_avg_W_per_K × 24.2 K / 1000)

The N3.7 in-use factor (PDF p.6097) tests three cylinder criteria:
  1. cert volume ≥ PCDB volume
  2. cert heat-exchanger area ≥ PCDB area (unless PCDB area = 0 per fn53)
  3. cert heat loss [(47)×(51)×(52)] ≤ PCDB heat loss

All three pass → 0.95; any criterion fails or is unknown → 0.60. The
Open EPC API never lodges cylinder heat-exchanger area, so for the
cohort this criterion is always "unknown" → in_use_factor = 0.60.

Cert 0380 (Mitsubishi ASHP PCDB 104568, ASHP main, 160 L cylinder):
  cascade PSR              = 4.39 / (127.158 × 24.2 / 1000) ≈ 1.4266
  cascade η_space,1_interp ≈ 235.24  (PSR-1.2 row 253.9, PSR-1.5 229.2)
  cascade η_water,3_interp ≈ 285.13  (PSR-1.2 row 287.7, PSR-1.5 284.3)
  cascade main_heating_eff ≈ 2.2348  (vs worksheet 2.2305, 1.9e-3 diff)
  cascade HW kWh/yr         ≈ 878.05 (vs worksheet 877.97, 0.08 kWh/yr)
  cascade SAP rating        ≈ 89.11  (vs worksheet 88.5104, +0.60)

The remaining +0.60 SAP residual is bounded by the ~0.4% PSR-formula
drift (the cascade computes PSR=1.4266 from (39)_annual_avg × 24.2 K
whereas the worksheet back-solves to ≈ 1.4321). Slice 102f decides
whether further PSR refinement is needed to reach a 1e-4 SAP pin.
2026-06-01 16:28:46 +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 pr review, move domain and orhcestration 2026-06-01 14:00:31 +00:00
sap10_calculator Slice 102e: heat-pump APM efficiencies via SAP 10.2 Appendix N3.6 / N3.7(a) 2026-06-01 16:28:46 +00:00
sap10_ml Slice 102b: cylinder storage loss via SAP 10.2 Tables 2/2a/2b 2026-06-01 16:28:45 +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