History: Concept: Dairy parlour propane load profile

Confidence: Verified (temperature targets, run-out consequences); Estimated (consumption ranges).

Operational reference for propane consumption on Ontario dairy operations. Dairy is propane's steady year-round livestock load — not as peaky as a poultry brooding event, but utterly intolerant of interruption.

Heat uses and temperature targets

Use	Target temperature	Notes
Pipeline / parlour CIP wash (main wash)	Start 71–77°C (160–170°F); return ≥49°C (120°F)	OMAFRA Raw Milk Specialist Mike Foran, Goat Gazette, June 2016
Bulk-tank wash	Mirror parlour wash; start ≥77°C	Cleaned after every pickup
Calf milk warming	38–40°C (100–104°F) at feeding	Body-temperature delivery; cold milk degrades abomasal performance
Calf-barn supplemental heat	Outcome-based; deep bedding + draft-free	NFACC 2023 Dairy Code (see `reg-nfacc-2023-dairy-code-calf-welfare`)
Teat-prep hot water	38–45°C at the wash bucket / udder spray	Continuous lower-grade draw
Office, shop, milkhouse space heat	18–21°C	Often the largest single annual draw in shoulder seasons

CIP wash quote (OMAFRA, Mike Foran): "hot wash — chlorinated alkali wash cycle (temperature at the start (74°C (165°F) or higher) and end (49°C (120°F) or higher)." Verified.

Estimated annual consumption and tank sizing

Operation	Annual propane (L)	Tank sizing typical
50–80 cow tie-stall, modest calf heat	3,000–6,000	500–1,000 USWG
100-cow parallel parlour, standard calf barn	5,000–10,000	1,000 USWG (3,028 L)
200-cow parlour, heated calf barn	10,000–20,000	1,000–2,000 USWG, often two tanks
300+ cow rotary or twin-robot + heated calf barn	15,000–30,000+	2,000–4,000 USWG manifolded

Confidence: Estimated. Operations with substantial separate calf housing (NFACC 2023 air-space minimums: 6 m³ per calf to 6 weeks, 10 m³ per calf to 12 weeks) commonly consume 50–100% more than parlour-only.

Run-out consequences specific to dairy

Parlour cannot wash → milk pickup at risk → DFO Grade A raw-milk standard infraction. The Ontario Milk Act, R.S.O. 1990, c. M.12, and the Milk Industry — Plants Regulation, R.R.O. 1990, Reg. 761, require defined sanitary standards; pickup is refused if CIP cleaning has not occurred to spec. Detail in reg-ontario-milk-act-propane-runout-exposure. Verified.
Bulk-tank temperature control compromised → SCC/IBC penalties. OMAFRA confirms milk must reach 1–4°C within two hours of first milking.
Calf-barn cold stress → mortality, scours, slow growth → visible 60 days later in heifer weights.

The economic asymmetry: a single missed milk pickup costs many times the price of an emergency tank fill. Keep-full + telemetry is not a luxury at this size — see op-livestock-telemetry-keep-full-considerations.

Sources

OMAFRA Raw Milk Specialist Mike Foran (Ontario Goat Goat Gazette, June 2016); NFACC 2023 Dairy Code; Ontario Milk Act, R.S.O. 1990, c. M.12; R.R.O. 1990, Reg. 761; OMAFRA bulk-tank cooling guidance.