Diamond Green Diesel, the joint venture between Darling Ingredients and Valero Energy, has grown into one of North America's largest renewable diesel platforms. It operates three plants in Louisiana and Texas with a combined capacity of roughly 1.2 billion gallons of renewable diesel and 470 million gallons of sustainable aviation fuel per year. The process uses hydrotreating and isomerization to convert waste fats, used cooking oil, and distillers corn oil into drop-in diesel that works in existing engines and infrastructure without blending limits or cold weather issues. Feedstock flexibility is a key advantage. Darling's global rendering network supplies low-carbon waste lipids, which earn favorable carbon intensity scores under California's Low Carbon Fuel Standard and federal renewable fuel programs. This policy support drives the economics by generating credits on top of diesel replacement value. The Port Arthur facility can swing between renewable diesel and sustainable aviation fuel as airline demand grows. The joint venture gives Darling a higher-value outlet for by-products from its core rendering and pet food businesses, while Valero contributes refining expertise and hydrogen supply. The result is a vertically integrated chain from slaughterhouses and restaurants to fuel terminals, producing fuel that helps decarbonize trucking, bus fleets, and aviation without requiring new engines or infrastructure.
