A planning article for Southwestern Ontario cash croppers. The OMAFRA consumption math (3.4 L per tonne per moisture point), worked examples at 500, 1,000, and 2,000 acres in normal and wet years, the October peak-week delivery requirement, tank-sizing logic, the cross-flow vs. mixed-flow efficiency picture, the pre-positioning calendar Perth and Huron operators run by, and the provincial scale of the season.
If you farm corn, soybeans, and wheat in Perth, Oxford, Middlesex, Huron, or Wellington, the propane question for the harvest year resolves into two numbers: the volume your dryer burns in its biggest week of October, and how much storage you need on the pad so that biggest week is not the week the truck is late.
This article is the planning version of those numbers. Where they come from in the OMAFRA benchmark, what they look like at 500, 1,000, and 2,000 acres in a normal year and a wet year, what the peak week demands of a delivery truck, how that maps to tank sizing, and the calendar most operators run by from August forward. The numbers are illustrative, not a quote.
The Ontario number to anchor every grain-drying calculation against is the OMAFRA continuous cross-flow benchmark:
A continuous cross-flow dryer uses 860,000 kJ of energy (34 L of propane) to evaporate this much water [134 kg of water removed to dry one tonne of corn from 25% to 15% moisture]. Burning 34 L of propane produces 52 kg of CO₂ emissions.
That works out to 3.4 litres of propane per tonne of grain, per moisture point removed, on a continuous cross-flow dryer. At a typical Ontario test weight of 25.4 kg per wet bushel, the per-bushel working figure for a 10-point dry (25% down to 15%) is 0.86 litres of propane per wet bushel.
The U.S. extension equivalent — Iowa State Extension PM 2089f — puts high-temperature drying at 0.018 USG of propane per bushel per moisture point on average, in a range of 0.015 to 0.022. Convert Ontario's 3.4 L/t/pt and you land at roughly 0.024 USG/bu/pt — at the top of the Iowa range, because Ontario's October and November ambient runs five to ten degrees Celsius colder than Iowa's peak harvest, and ISU's own data show drying cost rises about 14% per 20°F drop in average outdoor temperature. The Iowa numbers are useful for benchmarking; the OMAFRA figure is the one to plan against.
The same per-tonne math sized to three operations in three kinds of year. Assumptions: 180 bu/ac corn at 25.4 kg/bu, 0.86 L per wet bushel for a 10-point dry, scaled by moisture points removed. Propane at $0.80/L delivered, the May 2026 Southwestern Ontario agricultural benchmark.
| Operation | Corn acres | Normal year (4 pt removed) | Wet year (8 pt removed) | Dry year (2 pt removed) |
|---|---|---|---|---|
| 500-acre cash cropper | 500 | |||
| 1,000-acre cash cropper | 1,000 | |||
| 2,000-acre cash cropper | 2,000 | ~248,000 L | ~496,000 L | ~124,000 L |
Most Ontario years remove three to five points. An eight-point year — wet October, late kill-frost, corn coming off above 24% — doubles the propane bill versus a four-point year on the same acreage. The operation does not get to choose which column it is in until early October.
At $0.80/L delivered, drying corn from 25% to 15% costs about $27.20 per tonne, or about $0.69 per bushel, pre-HST. The Grain Farmers of Ontario Grain Drying Cost Calculator is the working tool for comparing that against a commercial elevator quote. The on-farm-versus-elevator answer flips with intake moisture, dryer efficiency, and the elevator's per-point rate plus shrink; there is no universal break-even.
The annual total is the easy number. The number that drives delivery scheduling and tank sizing is the biggest week.
Take a 1,000-bushel-per-hour dryer running 18 hours a day, six days a week, through the four-week peak. That is 432,000 bushels dried in the window — about a 2,400-acre footprint at 180 bu/ac. At 0.86 L per wet bushel for a 10-point dry, the four-week burn is roughly 371,000 litres, and the peak weekly delivery requirement is about 93,000 litres — roughly 24,500 USG, or one full bulk truck every two to three days at maximum harvest pace.
That peak typically lands in the week following the first hard kill-frost — mid-October in Perth and Huron, late October in Norfolk and Elgin — when standing corn moisture is locked in and combines run flat out. A truck two days late in that week is the difference between the dryer running and the combine sitting. The numbers scale linearly with throughput: a 600 BPH cross-flow on the same cadence burns about 55,000 L/week in the peak; a 1,500 BPH mid-size cross-flow burns about 140,000 L/week. The dryer is the bottleneck, and the bottleneck assumes the truck.
The propane tank set on the pad is sized by burner load and storage duration, not by acreage, against CSA B149.2 setbacks under O. Reg. 211/01 and the vaporizer threshold that kicks in once continuous draw exceeds what a tank can give up in cold weather. A working sketch by operation size:
Two flags at this calibre of installation: the TSSA 250-psig MAWP requirement took effect October 1, 2025, and distributors cannot fill non-compliant tanks; the federal E2 plan is independent of TSSA.
Cross-flow is still the most-installed Ontario design, despite mixed-flow and counter-flow being more efficient. The published Sukup figure (US OEM, flagged) is that mixed-flow with vacuum cooling reduces fuel consumption by 20 to 30% versus traditional pressure-heat / pressure-cool cross-flow. At a 1,000-acre operation drying 180,000 bushels a year, that range corresponds to roughly $20,000 to $30,000 a year in propane at the May 2026 benchmark.
OMAFRA Publication 24-005 Table 1 documents heat-recovery savings up to 15% on fuel and throughput gains up to 30% when grain moves hot from the dryer to a steeping or cooling bin — the wet-bin / dry-bin / cooling-bin architecture. Payback on OEM heat-recovery options on a new install is typically three to five harvest seasons at Ontario propane prices.
If you are not replacing the dryer this year, the OMAFRA tuning levers in priority order are: measure BTU per pound of water removed before changing anything; calibrate the burner's fuel/air mix; raise plenum temperature within OEM limits; seal and insulate the heat exchanger; and keep heat-exchanger screens clean. Measuring before adjusting is the one most often skipped and the one with the largest variance in payback.
The drying season runs mid-September through early December in Southwestern Ontario — wheat dust-off and early soybeans up front, the corn block from mid-October on, last corn coming off in early December. The biggest week is typically the one after the first hard kill-frost.
The calendar most Perth and Huron operators run by, working backward from that peak:
Contract structures, in increasing order of price exposure: summer-fill pricing (August–September), pre-buy contracts locking volume and price for a defined window, fixed-price contracts at one price for the full season with scheduled delivery, basis pricing floating against the Sarnia hub, and spot — last resort, and the price for being late to the August conversation.
One thing worth being plain about underneath this calendar: Agricorp Production Insurance does not cover supplier-driven propane stockout. A rail interruption, a distributor allocation, a force-majeure event — none are named perils. Pre-positioning is the protection.
Ontario corn averages four to five moisture points removed across a normal year. An eight-point year doubles the propane bill on the same acreage. The recent record runs: 2018 wet and snowy, late into November on full burn; 2019 wet and cold with the CN Rail strike inside the peak — worst-case stack; 2024 generally cooperative; 2025 drought-stressed in Eastern Ontario, softer drying season.
The pattern that matters for planning is not which year was wet but how quickly the year tips into the wet column. The decision the math forces is at August, not October: contract structure and pre-positioning are committed against a wet-year envelope on every operation that cannot afford an October spot purchase.
The 2019 strike sits behind this article as a reference event rather than its subject. The math above assumes a working supply chain — a Sarnia fractionator producing molecule, a truck route to Perth that moves on schedule, a dispatch line that answers. When the supply chain falters, the math is no longer the binding constraint; allocation is. The longer version of that story — the rail-dependence numbers, the CPA allocation hierarchy, what Tier 3 looks like for an operator without livestock — is in the greenhouse article. Grain dryers without livestock sit on the same tier.
Ontario harvested 2.1 million acres of corn for grain in 2025 at 175.6 bu/ac, producing 9.5 million tonnes at 15% moisture (Statistics Canada The Daily, December 4, 2025). Drying that production from typical intake moisture consumes roughly 130 million litres of propane in a normal year, climbing toward 250 to 300 million litres in a wet year with eight or more points removed across the province. The 2026 planted-intentions number is 2.3 million acres — about a 5.4% lift on planted area, on track to lift the propane requirement at the same rate.
A few claims that occasionally appear in trade conversation are not in this article because the verified primary sources do not support them at present:
The article will be updated when verified primary sources support tighter answers on any of these positions.
A named rep takes the call, not a queue. Tell us about your operation — we’ll sort coloured diesel, clear diesel, propane, and DEF in one conversation.
Standing routes across nine regions. Same rep year-round; off-hours emergency dispatch through the same number.
Marketing Intelligence by Candid