Southwest Airlines has announced a significant supply agreement with Valero Energy Corporation, securing up to 25 million gallons of sustainable aviation fuel (SAF) for operations at Chicago Midway International Airport (MDW). This deal represents Illinois' largest SAF supply agreement to date.

This agreement follows Southwest's updated sustainability strategy, "Nonstop to Net Zero," which outlines its climate objectives, including achieving net-zero emissions by 2050. The airline aims to reduce emissions intensity by 25% by 2030 and 50% by 2035, with a goal of replacing 10% of its total jet fuel consumption with SAF by 2030.

Under the terms of the agreement, Southwest will purchase at least 3.6 million gallons of neat SAF (approximately 12 million gallons when blended) for its operations, beginning in the fourth quarter of 2024. The agreement also includes an option to purchase up to 25 million gallons of neat SAF (around 84 million gallons blended), which could account for up to 35% of the airline’s jet fuel usage at MDW based on last year’s consumption.

The neat SAF will be supplied by Diamond Green Diesel, a joint venture between Valero and Darling Ingredients, which produces renewable fuels from recycled animal fats, used cooking oil, and inedible corn oil. This SAF will be blended with Valero’s conventional jet fuel and delivered using existing fuel infrastructure. According to Southwest, the lifecycle greenhouse gas emissions reduction from this SAF ranges from 74% to 84% compared to conventional jet fuel.

This agreement was facilitated by the Illinois Sustainable Aviation Fuel Purchase Credit and support from customers involved in Southwest's Scope 3 SAF Program, highlighting the airline's commitment to advancing sustainability in the aviation sector.