dunkin’ donuts just took its famous ‘america runs on dunkin’ slogan to the next level by designing a transportable tiny home that literally runs on discarded dunkin’ coffee grounds. the mobile structure is fueled by a biofuel blend using 80 percent coffee oil extracted from about 65,000 pounds of used grounds. the restaurant chain worked with blue marble biomaterials — a sustainable biochemical company — to extract excess oils in the spent coffee grounds, mix, react, and refine the biodiesel. every 170 pounds of spent coffee grounds yields about one gallon of fuel and is used in a standard biofuel generator.