The World War II era also gave birth to the first electronic digital computer, the Electronic Numerical Integrator and Computer, or ENIAC. Funded by the Defense Department, the machine was built to compute ballistics tables that soldiers used to mechanically aim large guns. For years it was located at Aberdeen Proving Ground.
This decade, the Pentagon determined that garbage on military bases poses a serious logistical problem.
"When you're over in a combat area and people are shooting at you, you still have to deal with your trash," said John Spiller, project officer with the Army's Rapid Equipping Force, which is funding the Tiger project. "How would you feel if somebody was shooting at you every other time you pushed it down the curb?"
He and other Army officials said they could not recall any specific attacks against troops or contractors heading to dumpsites.For years, large incinerators have burned trash to generate power. Baltimore Refuse Energy Systems Co., the waste-to-energy plant near the stadiums, consumes up to 2,250 tons of refuse a day while producing steam and electricity.
The process is so expensive that it has only made sense to do it on a large scale, scientists say.
The military has spent almost $3 million on two Tiger prototypes, each weighing nearly 5 tons and small enough to fit into a 20- to 40-foot wide container. The project is being developed by scientists from the Edgewood, Va.-based Defense Life Sciences LLC and Indiana's Purdue University.
The biggest challenge was getting the parts to work together, said Donald Kennedy, an Edgewood spokesman. Because the Tiger is a hybrid consisting of a gasifier, bioreactor and generator, much of it is built with off-the-shelf items, including a grinder.
Another big challenge: expectations.
"When we would initially talk to people about the Tiger system, a large percentage would refuse to believe it could actually work," Kennedy wrote in an e-mail. "Alternatively, a similar percentage would be so intrigued by the idea that they would demand to know when they could buy one for their neighborhood."
The Tiger works like this: A shredder rips up waste and soaks it in water. A bioreactor metabolizes the sludge into ethanol. A pelletizer compresses undigested waste into pellets that are fed into a gasification unit, which produces composite gas.
