Grain Dryer Sizing Calculator

It matches the engineering method used by dryer dealers and grain handlers, and lands within a realistic range for honest input. The biggest accuracy drivers are your incoming moisture estimate and the dryer efficiency you select. Real fuel use can vary up to 25% from published averages depending on ambient temperature, airflow and dryer condition — always check a specific model's PAMI test report before buying.

Manufacturers measure dryer capacity by how many bushels they can dry per hour while removing 5 points of moisture (for example 20% down to 15%) at 70°F. It is an industry-standard benchmark so dryers can be compared fairly. If your job removes more than 5 points, real throughput drops — roughly 14% for each extra point — which is why this calculator converts your job back to a rated figure.

Drying cost scales almost directly with points removed, because each point means evaporating more water and burning more fuel. Alberta farm-management figures put oilseed drying at roughly 10 to 16 cents per bushel per point. Pulling canola from 17% to 9.5% — about 7.5 points — can run $0.75 to $1.20 per bushel before capital and labour.

A modest buffer is wise — this calculator already adds 20% for peak moisture and downtime. Beyond that, oversizing ties up capital that could go elsewhere. The exception is if you expect acreage to grow within a few years, or you regularly face wet, late harvests where every drying hour counts. In those cases the next class up often pays for itself.

Where a farm has access to a natural-gas line, gas is materially cheaper per unit of energy than propane, which is why many high-volume Prairie operations install it. Propane remains the practical choice for farms without a gas connection. The calculator lets you enter either fuel at your local price (propane per litre, natural gas per GJ) so you can compare directly. SaskEnergy publishes a grain-drying estimator comparing the two.

About 20 hours is a sensible planning figure once you account for loading, unloading and maintenance. Some operations run continuous-flow dryers nearly around the clock during a wet harvest, but planning for 20 leaves margin. Fewer available hours means you need a higher-capacity dryer to move the same daily volume.

Canola is an oilseed with small, oil-rich seeds that scorch easily and can even ignite at high air temperatures. It must be dried slower and cooler than cereals, which lowers real throughput well below a dryer's rated figure. Flax behaves similarly. Cereals like wheat, barley and oats tolerate higher heat and dry faster.

Efficiency is measured in BTU per pound of water removed. Modern high-efficiency mixed-flow dryers run near 1,500 BTU/lb; modern continuous towers around 2,000; older cross-flow units near 2,800; and simple batch or bin dryers around 3,500. If you don't know your dryer's figure, "Modern tower / continuous (2,000)" is a safe default for most current equipment.

Yes. Corn is included and is the heaviest dry of all the crops, holding three to four times the water of wheat per bushel. Because corn often comes off at 20–28% moisture, drying capacity and fuel cost climb quickly — exactly what dominates Eastern Canadian drying bills. Enter your real incoming moisture for an accurate result.

A batch dryer fills, dries a fixed load, then unloads — simple and lower cost, common on smaller farms. A continuous-flow dryer takes in wet grain at the top and discharges dry grain at the bottom without stopping, giving far higher throughput and steadier grain quality. Most operations above a few thousand bushels a day move to continuous flow.

The biggest levers are fuel choice (natural gas where available), dryer efficiency (a high-efficiency mixed-flow unit can use up to 40% less fuel than an old batch dryer), and not over-drying. Drying only to your market target — not below it — saves both fuel and lost weight. Heat-recovery systems pay back within a few seasons on high-volume operations drying 250,000+ bushels a year.

It's tempting but costly. Over-drying burns extra fuel and removes weight you sell by the bushel, so you pay twice. The calculator stops at your target moisture for that reason. Aim for your market or safe-storage target and use aeration in the bin to hold and fine-tune from there.