Quantifying the benefits of biofuels
June 16, 2008 In the world’s race to reduce greenhouse gas emissions and solve the fossil-fuel shortage, the use of biofuels based on renewable sources is considered to be an environmentally friendly solution to the fuel shortage and global warming. However, there are two sides to the debate, and research from the University of Washington strengthens the argument that some food-based biofuel stocks could be causing more harm than good.
A University of Washington, research team studied how much energy was required to produce corn-based ethanol. The paper describing their findings was based on a year-long study and was published in the June issue of the journal Conservation Biology. The team researched the impact on soil fertility and effects on food supply when fuels based on crops such as corn and soybeans are mixed with fossil fuels. They discovered that the large amounts of energy required to grow corn and then convert it to produce ethanol had a net energy gain that was modest and that corn-based ethanol was the worst offender amongst the alternative energy fuels. Using another crop such as switchgrass, or using algae would use significantly less energy to produce fuel but the technology to achieve this is not fully developed.
"It's foolish to say we should be developing a particular biofuel when that could mean that we’re just replacing one problem with another," said lead author Martha Groom of the UW Bothell.
The paper's policy suggestions are "not definitive at all," Groom said, "but rather each category calls out a question and is a starting point in trying to find the proper answers."
These concerns are becoming more acute with the rapid rise of both food and fuel prices, she said. The issue is especially touchy for farmers who might for the first time be realizing significant profits on their crops, but it also is a serious concern for motorists.
"I've heard about people getting their gas tanks siphoned, and I hadn't heard of that since the '70s," she said. The aim of the study was to evaluate options for biofuel development and to find the most ecologically promising alternatives. The researchers developed twelve recommendations which will help to ensure that biofuels produced in the future will be sustainable and carry a smaller ecological footprint.
- Policy Recommendations
In related biofuel news, a team of researchers from Iowa State University and the University of Hawai’i discovered that they can save energy, recycle more water and improve the livestock feed that’s a co-product of fuel production by growing a fungus in ethanol production leftovers.
Ethanol production produces a product called thin stillage of which only 50% can be recycled, with the rest normally having to be evaporated which is a costly exercise. The researchers added a fungus, Rhizopus microsporus, to the thin stillage and found it would feed and grow. The fungus removed about 80 percent of the organic material and all of the solids in the thin stillage, which meant the remaining water and enzymes in the thin stillage could be recycled back into production. The fungus can then be dried and used as livestock feed.
This new research has the potential to save ethanol producers millions of dollars every year.