Distiller's Grains

Wet distiller grains with solubles (WDGS) are typically produced by dry mill plants that are located close to cattle feedlots. Dry distiller grains (DDGS) are sold as a high-quality livestock feed. Because of high fiber content, DDGS is used mostly for ruminant feed and is consumed in geographic regions with high dairy or beef cattle concentrations. A bushel of corn produces 16 to 18 pounds of DDGS, so a typical 100 million-gallon dry mill operating at nameplate capacity will produce between 295,000 and 333,000 short tons of DDGS annually.

The economic advantage of WDGS over DDGS to ethanol producers is the elimination of the drying process. Drying wet grains to produce DDGS can increase the energy consumption of older, less efficient plants by up to 50 percent. However, WDGS have a very limited "shelf life" and are more expensive to transport due the much higher water content. Such factors limit the effective WDGS geographic sales radius to no more than 100 miles from the ethanol plant. Drying WDGS extends the "shelf life" of the feed from 2 weeks to several months and reduces associated transportation costs.