Model → ECM calculations (ECM-ADAPT)

Typed adapter: EQ-VOCAB quantity records + scenario → open_fdd.ecm_engineering.calculate. Python stays on PyPI — not on the product HTTP path.

from open_fdd.ecm_engineering import adapt_model_to_calculator

qty = {
    "schema_version": "ofdd_engineering_quantities_v1",
    "quantity_id": "q-elec-1",
    "property": "ratedElectricalInputPower",
    "numeric_value": 18.5,
    "unit_code": "kW",
    "quantity_kind": "ElectricalPower",
    "value_basis": "Rated",
    "source_type": "nameplate",
    "review_status": "Reviewed",
}
out = adapt_model_to_calculator(
    "fan_affinity",
    [qty],
    {
        "hours": 4000,
        "baseline_speed_fraction": 1.0,
        "proposed_speed_fraction": 0.8,
    },
)
assert out.ok
print(out.result["savings_kwh"])

Supported methods (v1 adapter)

Method	From model	From scenario (required)
`fan_affinity`	`ratedElectricalInputPower` (kW, ElectricalPower)	hours, baseline/proposed speed fractions
`schedule_reduction`	`ratedElectricalInputPower`	baseline/proposed annual hours
`kw_per_ton_improvement`	(optional capacity context only)	annual_ton_hours + baseline/proposed kW/ton

Honesty: capacity-only cooling records without annual_ton_hours return capacity_only in missing_evidence — nameplate tons are not annual load. Thermal kW cannot satisfy electrical design_kw.

Versioned context envelope (ecm_context_v1) remains complementary for agent screening; this adapter is the calculator boundary.