History: Concept: K-factor for livestock vs. residential — why ambient degree-day is insufficient

Confidence: Inferred — operational principle; specific algorithm details vary by telemetry vendor.

Companion to op-degree-day-keep-full (residential-flavoured K-factor). This entry captures why residential K-factor models break on livestock accounts — and what to do instead.

Residential K-factor

Tracks ambient temperature ≈1:1; degree-day model works. Detail in op-degree-day-keep-full.

Livestock K-factor — degree-day alone is insufficient

Broilers: the brooding curve shifts the early-cycle K-factor dramatically. The first 7 days of a flock consume ~50% of cycle propane (see op-poultry-barn-propane-load-profile). A degree-day model that doesn't recognize the cycle phase will under-estimate consumption catastrophically in week 1.
Dairy: parlour wash cycles dominate. Process heat (CIP wash, calf milk warming, teat-prep hot water) does not track ambient 1:1. A milking parlour pulls hot water on a clock cycle, not a thermostat. Detail in op-dairy-parlour-propane-load-profile.
Hogs: creep heat is dual-zone. The piglet zone runs at up to 34°C while the room runs at 18–20°C; the creep load decouples from room ambient. Detail in op-hog-barn-propane-load-profile.

The leading cause of preventable run-outs

Treating a 20,000-bird broiler barn like a residential propane account is the leading cause of preventable run-outs on Ontario livestock operations. A residential K applied to a brooding-week broiler barn under-estimates burn so badly that the auto-deliver trigger fires after the tank has already emptied.

Operational test for distributors

Ask the distributor whether their telemetry software uses livestock-specific K-factor profiles or runs the account on a residential K. The answer matters operationally — and it's a competitive differentiator. Most residential-focused dispatch software does not handle livestock cycle structure natively.

What "livestock-specific K" looks like in practice

Broiler: K reset every flock; cycle-phase weighting (week-1 multiplier, week-by-week decay).
Dairy: K driven by milking schedule and cow count, not just ambient.
Hog: dual-zone K that recognizes creep load as separate from ambient load.

Detail on telemetry vendor support and trigger settings in op-livestock-telemetry-keep-full-considerations.

Sources

Field experience consolidated from SW Ontario livestock distribution practice. Specific algorithm details vary by telemetry vendor; see service-tank-monitoring-telemetry for the vendor list.