Ethanol Yield Calculator

Ethanol yield depends first on which feedstock is being processed, since different biomass sources contain very different amounts of fermentable sugar or starch per ton. This calculator applies an approximate typical/reference yield figure per feedstock type -- roughly 98 gallons per short ton for corn (reflecting the commonly cited ~2.8 gallons of ethanol per bushel of corn from real dry-mill operations), roughly 20 gallons per ton for sugarcane (cane itself, not just extracted sugar), and roughly 70 gallons per ton for cellulosic feedstocks like switchgrass or wood. These figures already reflect real-world achieved commercial yields, not an unreached stoichiometric theoretical maximum, and the calculator multiplies that reference figure by feedstock tonnage and by your entered conversion efficiency, which represents how your specific operation's yield compares to that typical/reference figure for the feedstock: 100% means your process matches the reference yield, and lower values model an operation running below it.

Every ton of feedstock processed also produces a byproduct: dried distillers grains (DDGS) from corn, bagasse fiber from sugarcane, or lignin residue from cellulosic material, each estimated at an approximate weight per ton depending on feedstock type. The energy balance ratio is reported as a fixed value per feedstock type, representing the approximate ratio of energy contained in the ethanol produced to the fossil energy consumed making it -- corn ethanol's ratio is typically cited as the lowest of the three (around 1.6:1), while sugarcane and cellulosic pathways are generally cited with substantially higher ratios in published energy-balance literature, reflecting differences in how energy-intensive each feedstock's cultivation and processing is. All figures here are representative approximations for comparing feedstocks and scenarios, not a substitute for a site-specific engineering study.