More Galleries
50 years of the Ford Mustang Take a drive down memory lane with our favorite photos of the car through the years. More
8 CEOs who took a pay cut in 2013 Median CEO pay inched up 9% in 2013 to $13.9 million. But not everyone got a bump last year. Here are eight CEOs who missed out. More
10 best convertibles now that spring has sprung It's finally time to put the top down. Here are our 10 favorite rides for the warmer months to come. More
4 of 5
Cellulosic ethanol
Cellulosic ethanol

Pluses: Made by breaking down wood chips, farm waste, and nonfood crops like grasses, cellulosic ethanol wouldn't require diverting the use of cropland. Scientists are making progress at breaking down plants' tough cellulose and lignin molecules, the key to turning nonfood biomass into fuel.

Minuses: Still costly and difficult to make, ethanol produced from nonfood plants is more energy intensive than that made from corn and sugar cane. By one estimate, putting all the grassland in the U.S. into fuel production could replace only about 10% of petroleum.

NEXT: Algal biofuel
Last updated April 22 2008: 7:09 AM ET
Market indexes are shown in real time, except for the DJIA, which is delayed by two minutes. All times are ET. Disclaimer LIBOR Warning: Neither BBA Enterprises Limited, nor the BBA LIBOR Contributor Banks, nor Reuters, can be held liable for any irregularity or inaccuracy of BBA LIBOR. Disclaimer. Morningstar: © 2014 Morningstar, Inc. All Rights Reserved. Disclaimer The Dow Jones IndexesSM are proprietary to and distributed by Dow Jones & Company, Inc. and have been licensed for use. All content of the Dow Jones IndexesSM © 2014 is proprietary to Dow Jones & Company, Inc. Chicago Mercantile Association. The market data is the property of Chicago Mercantile Exchange Inc. and its licensors. All rights reserved. FactSet Research Systems Inc. 2014. All rights reserved. Most stock quote data provided by BATS.