Meet the Energy Superbugs: Extremophiles
Extremophiles are tiny microbes that are able to thrive in hot, salty and even acidic or gaseous environments that would kill other forms of life. Now scientists are using these hardy dwellers of the seafloor and hot springs to produce biofuels like ethanol more efficiently and at lower cost.
These heat and salt-loving microorganisms are good at breaking down biological material like wood chips, waste crops or other sorts of plant material. They also literally "take the heat" when it comes to punishing industrial processes. Until recently, researchers have had trouble culturing these wild-growing extremophiles and harnessing their properties. But recent advances have allowed them to turn them into bio-powered refineries.
"I believe they will be a big generator for energy in the near future," said Rajnesh Sani, assistant professor of biological and chemical engineering at the South Dakota School of Mines and Technology. "We had some trouble at first, but in the past five years, we've learned how to culture them. Now they cooperate and grow nicely with us."
Sani found a trove of unique extremophiles at the bottom of the 7,800 foot-deep Homestake Gold Mine in Lead, S.D. The bacteria were living in the warm soisl and in the fissures between the rocks at the bottom of the mine.
"Outside it was snowing," Sani recalls. "But at the bottom of the mine it was 40 to 45 degrees C (104 to 113 F). We we're sweating."
Sani and his colleagues cultured the Geobacillus bacteria and used it to break down corn waste and cord grass from solid to liquid at nearly 160 degrees F. This fermentation process has long been used to produce biofuels -- and beer -- but now it can be done in fewer steps, using less water and smaller reactor vessels, explained Sani.
"We are trying to eliminate some steps to make it more cost effective," Sani said.