Paddy at 23% Moisture: Sell Wet, Sun-Dry or Use a Mechanical Dryer?
After a 6-hour combine harvest, Sushila has 6,000 kg of paddy at 23% moisture (w.b.). The local miller offers ₹1,850 per quintal as-is, or ₹2,200 per quintal if the lot is at 14% moisture. She can sun-dry on a clean tarpaulin; labor and tarpaulin charges are ₹1,400, and two sunny days are needed. The forecast gives a 40% chance of rain on the second day; if rain wets the drying lot, she expects a 10% price discount from the 14% price. A custom mechanical dryer can dry the lot to 14% for ₹1,200 per tonne of wet paddy, with an additional 1% handling loss. Her storage shed is dry but not aerated; grain temperature is 32°C. She needs cash within a week. The miller will not accept grain above 14% moisture unless it is sold at the as-is price.
1. Calculate the weight at 14% moisture and compare the net returns of immediate sale, sun drying, and mechanical drying. Include the rain-risk expected value. Which option would you recommend and why?
Read the worked answer
Final weight at 14%: 6,000 × (100−23)/(100−14) = 6,000 × 77/86 = 5,372 kg = 53.72 qtl.
Immediate sale: 60 qtl × ₹1,850 = ₹111,000.
Sun drying: 53.72 qtl × ₹2,200 = ₹118,184; minus ₹1,400 = ₹116,784 if no rain. If rain causes a 10% price cut: 53.72 × ₹1,980 = ₹106,366; minus ₹1,400 = ₹104,966. Expected value = 0.6 × 116,784 + 0.4 × 104,966 = ₹112,057.
Mechanical drying: wet paddy after 1% handling loss = 5,940 kg at 23%; final = 5,940 × 77/86 = 5,319 kg = 53.19 qtl. Sale = ₹117,018; minus dryer cost (6 t × ₹1,200 = ₹7,200) = ₹109,818.
Recommendation: If she can protect the tarpaulin and turn the grain quickly, sun drying has the highest expected value (₹112,057), but the downside is ₹104,966 and cash is needed within a week. Immediate sale is the safest certain option at ₹111,000. Mechanical drying is not economic at this price unless rain is certain. A risk-averse farmer with no covered drying space should sell wet; one with labor and a tarpaulin can sun-dry.
2. What harvest and drying practices would you insist on to protect quality? Include moisture measurement, grain depth, turning, and storage.
Read the worked answer
Harvest at 20-22% moisture if the combine can handle it; 23% is acceptable but the grain must not be piled wet. Measure moisture with a calibrated meter, not by bite. Dry in a thin layer (about 5 cm) on a clean tarpaulin, turn every 2-3 hours, and cover at night. Target 14% or below for storage; do not mix wet and dry lots. Keep grain temperature below 30°C and aerate the shed; bag only after the grain has cooled. Clean the combine and bags to avoid mixing varieties. Do not dry on a road or bare soil, and do not pile hot grain in airtight bags.
3. If rain starts during drying, what immediate contingency would reduce losses? What would you not do?
Read the worked answer
If rain starts, cover the lot immediately with a tarpaulin, move it under cover, and spread it thin; do not leave it in a deep heap where heating and mold begin. If the grain is already above 14% and rain continues, use the mechanical dryer or sell wet rather than store. Aerate the shed and inspect for heating and off-odour. Do not dry by mixing with dry grain, do not add water to 'bring back' weight, and do not store above 14% moisture. If the lot has heated, cool and dry it before bagging.