Biofuels, mainly ethanol, now account for one-tenth of car fuel consumed in the United States and that number is set to rise. But are biofuels the silver bullet for the looming energy crisis? This week, Citlalli and Lindsay tackle that question head-on. They start their journey following the life cycle of fats, oil and grease in San Francisco and end up with a startling conclusion about the future of fuel in America. Along the way, they reveal a number of ethanol’s secrets. Like, did you know that if you convert all of the world’s main grains (corn, wheat, rice) into ethanol, you would only be able to supply half of all petrol consumption? Yup, and there’s more where that came from. Listen below for the full story.

Produced by Citlalli Sandoval and Lingzhi Jin. Guests include: Dogpatch Biofuels, San Francisco’s only biodiesel gas station; Karl Knapp, Associate Professor for Stanford’s Department of Civil Engineering; David Lobell, Associate Director of the Center for Food Security and the Environment at Stanford; and Eric McAfee, entrepreneur, VC and philanthropist in the renewables field. Music is “Tony Dubshot 04-Beta Stability” from the Free Music Archive.