Army Turning Trash Into Energy

June 19, 2008
by Lindy Kyzer
WASHINGTON - Getting rid of garbage is a problem anywhere, but particularly at forward operating bases in Iraq and Afghanistan.

Pair that with the constant need for fuel and the push for alternative energy sources, and you have the stuff of science fiction - the Tactical Garbage to Energy Refinery, or TGER, which is already turning trash into energy at Camp Victory, Iraq.

Dr. James Valdes, scientific advisor for biotechnology with the U.S. Army Research, Development and Engineering Command, participated in a blogger's roundtable Tuesday to discuss how TGER works and how it could be used in the future.

Valdes and his fellow scientists at RDECOM recently sent two prototypes of the TGER to Camp Victory to put these energy-generating trash disposers to the test.

"Our initial idea was that we could generate fuel in theater," said Valdes. He said fuel has historically been the top "logistical nightmare" for a deployed army.

Seeing an opportunity to use biotechnology to solve a real Army problem set Valdes and his team on the path toward creating a machine that could provide the energy to power the generators and stoves that make up about half of the fuel consumption at most forward operating bases, according to Valdes.

"We've got a lot of garbage at various operating bases, and it's got to go someplace," said Valdes. "So our logic was that at a forward operating base, could we use the garbage to make fuel and thereby get rid of the garbage and help to keep the convoys off the streets? And so that's how TGER got started."

TGER is small enough to fit into a CONEX container, but powerful enough to power a standard 60-kilowatt generator. TGER works by turning the solid trash into fuel pellets which are fed into a down-draft gasifier. The gasifier then heats the pellets, and breaks them down into a synthetic gas composed of simple hydrocarbons that resembles low-grade propane. TGER processes the liquid and food waste into a hydrous ethanol which is blended with the syngas to create usable energy.

It takes TGER just six hours to fully power up, during which time the amount of diesel fed into the machine slowly drops, until the generator is powered by less than one gallon of fuel per hour, as compared to five per hour without TGER.

"And as one might think, the sort of waste stream that goes into TGER is a mixed waste stream: it's paper; it's plastics; it's ammunition papers; it's food-slop garbage. And so getting a really high-quality fuel source out is kind of a problem," Valdes said. "So we decided instead to design a system that would convert the trash into electrical power.

The 90-day test at Camp Victory will help determine future applications for TGER. With temperatures soaring toward 112 degrees and limited infrastructure at the base, it's a formidable testing environment.

"Once we're through with this 90-day testing time, we have to analyze those data, and then we'll do a clean-sheet engineering design," Valdes said.

One of the potential applications Valdes already sees is the potential for TGER to be used in post-Katrina-type scenarios, where energy is scarce but trash is readily available.

http://www.military.com/news/article/army-news/army-turning-trash-into-energy.html?col=1186032369115