Some alternative vehicle fuels such as liquid coal can cause more harmful greenhouse gas emissions than polluters such as petrol or diesel, the Union of Concerned Scientists warned in a study released Tuesday. The organization’s press release stressed the need for “life cycle analysis” of various alternative fuel sources to determine which are the best in terms of lowering overall carbon emissions.
“We need to wean ourselves off oil, but we should replace it with the cleanest alternatives possible,” said Patrician Monahan, author of the report and deputy director of UCS’s Clean Vehicles Program. “Let’s not trade one bad habit for another.”
Liquid coal, for example, can release 80 percent more global warming pollution than gasoline, the report found. Corn ethanol, conversely, could be either more polluting or less than gasoline, depending on how the corn is grown and the ethanol is produced. On average, corn ethanol can reduce emissions about 20 percent, though there is uncertainty due to differing land use practices. The cleanest alternative, cellulosic ethanol from grasses or wood chips, could reduce emissions by more than 85 percent.
“Biofuels have a Jekyll and Hyde reputation depending on what study you read and what assumptions you make,” Monahan said. “But liquid coal is a loser no matter how you look at it. We need to set standards so farmers know the right way to produce cleaner fuels.” She also cautioned that we must ensure that biofuels and other alternative fuels do not threaten the environment or limit food production.
You can read the UCS press release here and download the complete study here.
