Freeze Dryer Batch Time Planner
Pick your machine, choose a food, and set the slice thickness. Get an estimated run time in hours, electricity cost for the batch, and how much freeze-dried food you will end up with. Save your batches to a local log. Everything runs in your browser - nothing uploaded.
Estimated batch time
Add 2-4 h buffer for a final check
Energy used ?
kilowatt-hours
Electricity cost
at your rate
Fresh food loaded
across all trays
Freeze-dried yield ?
moisture removed
Learn more: Freeze drying batch planning
How freeze drying time is calculated
Freeze drying removes moisture by freezing food solid, then reducing air pressure so ice turns directly to vapor without going through a liquid phase. The baseline drying time depends on the food type - fresh strawberries typically take 20 hours in a Harvest Right Standard. Thickness adds a multiplier: thin slices (~3mm) cut the time by 30%, while chunks (~20mm) extend it by 60%. A light load (under 70% of recommended weight per tray) completes faster because less total moisture needs to escape. For example, a medium-thickness batch of strawberries might run 20 hours baseline, but increase to 26 hours if cut into thick pieces, or drop to 17 hours if sliced thin.
Understanding electricity cost and real payback time
Each batch consumes kilowatt-hours based on machine wattage multiplied by run time. A Harvest Right Standard (1500W) running 20 hours at USD 0.15 per kWh costs USD 4.50 in electricity. Freeze-dried food stores for 20-25 years with proper packaging, but payback depends on the cost difference between buying freeze-dried vs. fresh or preserved alternatives. Most home users break even on equipment costs within 2-3 years of regular batching, assuming you'd otherwise buy expensive freeze-dried products. Track actual run times and yields to refine your cost model over several batches.
FAQ
How does thickness affect freeze drying time?
Thicker slices trap more moisture and take longer to dry completely. The calculator uses thickness factors: thin slices (~3mm) = 0.7x baseline hours, medium (~6mm) = 1.0x baseline, thick (~12mm) = 1.3x, and chunks (~20mm) = 1.6x. For example, strawberries freeze-dry in ~20 hours at medium thickness, but 32 hours for chunks. Slice thickness is the single biggest controllable variable - thinner, more uniform cuts dramatically speed up your cycle and save electricity.
What's the relationship between load and batch time?
A light load (less than 70% of the tray's recommended max weight) finishes faster because there's less moisture to remove overall. The calculator applies a 0.85x load factor for light loads and 1.0x for full trays. A light batch of strawberries might finish in 16 hours instead of 20. However, running partially full trays wastes energy and cost per unit of food - it's more efficient to fill the machine completely if your timeline allows.
How is electricity cost calculated?
Cost = (machine watts / 1000) × hours × rate per kWh. A Harvest Right Standard (1500W) running for 20 hours at USD 0.12 per kWh costs: (1500/1000) × 20 × 0.12 = USD 3.60. Most US average electricity costs USD 0.12-0.15 per kWh; check your utility bill for your exact rate. Commercial operations with higher rates should input their local cost. The calculator's estimate becomes very accurate for planning batch costs and payback ROI on the equipment.