Before we talk about future fuels, it’s important to spell out some definitions.
A biofuel is a fuel that is produced through contemporary biological processes. I know that’s quite a mouthful for a definition, but it takes in agriculture, plants growing wild in the forest, field crops like corn, ocean grasses, and even anaerobic digestion. In fact, biofuels can be derived directly from plants, or indirectly from agricultural, commercial, domestic, and/or industrial waste.
Contrast that with the geological processes that produce fossil fuels such as coal and oil, which come from prehistoric biological matter.
There are three challenges to making biofuels. First, breaking down woody cellulose and lignin polymers into simple plant sugars. Second, converting those sugars into fuels that will work into existing vehicles, either through a thermochemical process using high temperatures and pressures, or by a biochemical process using enzymes or bacteria. And third, doing all of that cheaply and on a large scale.
And it’s that third challenge that is proving to be the biggest problem. While scientists have long known how to convert various kinds of organic material (wood chips, grasses, seaweed, animal fats) into fuel, producing large amounts of biofuels has always been more expensive and less convenient than turning oil into gasoline.
The oil giant Shell, for example, was working on ten advanced biofuels projects in 2008. Most of them are shut down now. But it’s not because the technology didn’t work. In fact, all of them did. But while fuel could be produced in the labs and even in larger demonstration projects, it couldn’t be made cheaply and in a large enough quantity to make the process economical.
Until the plummeting price of oil dramatically slowed the biofuels industry, the production of biofuels was growing. In 2010, worldwide biofuel production reached 105 billion liters (28 billion gallons US), up 17% from 2009, and biofuels provided 2.7% of the world's fuels for powering cars and trucks. Most of that is made up of ethanol and biodiesel.
While biofuel research and production has slowed, several companies are putting the finishing touches on industrial-scale plants that will go on-line in the next year. There’s no doubt gas prices will go up, but the question still remains whether biofuels will ever be able to economically compete.
Frank Graff is a producer/reporter with UNC-TV, focusing on North Carolina Science Now, a weekly science series that airs Wednesdays, beginning in August 2013, as part of North Carolina Now on UNC-TV. In addition to producing these special segments, Frank will provide additional information related to his stories through this North Carolina Science Now Reporter's Blog!