United Airlines has inked a purchase agreement with AltAir Fuels for cost-competitive, sustainable, advanced biofuels at commercial scale.

As per the agreed terms, United will purchase 15 million gallons of lower-carbon, renewable jet fuel over a three-year period, with the option to purchase more.

According to the company, AltAir Fuels will retrofit part of an existing petroleum refinery to become a 30 million gallon, advanced biofuel refinery near Los Angeles, California.

This facility will convert non-edible natural oils and agricultural wastes into approximately 30 million gallons of low-carbon, advanced biofuels and chemicals annually.

Commenting on the deal, United Airlines Global Environmental Affairs and Sustainability managing director Jimmy Samartzis said the agreement demonstrates the company’s commitment towards alternative fuels as well as its efforts to lead commercial aviation as an environmentally responsible company.

AltAir chief executive officer Tom Todaro said, "United Airlines has been a strategic partner for several years as we work to establish our biofuel facility.

"We cannot overestimate how important this milestone is for the commercialization of sustainable aviation biofuels, and we at AltAir are proud that United is our first customer."

AltAir will start delivering five million gallons of renewable jet fuel per year to United starting in 2014.