As the airline industry races to meet its goal of 10% biofuel use by 2017, experts say the economics appear daunting. While a gallon of crude oil costs about 90 cents today, the same amount of oil extracted from algae costs about $20. Jatropha and camelina oil, meanwhile, cost $7 and $3 per gallon, respectively. But experts say the cost of extracting petroleum from the earth will continue to climb, while technological advances will drive down the cost of biofuels, which can be switched out as needed. "We very strongly believe that it's a portfolio of correct answers," says an official with Boeing Commercial Airplanes. "There will be different plants, different processes, different regional solutions that, for a user, can be interchangeable."