Pragmatism driving new energy programs on U.S. military bases.

• Author: Magnuson, Stew
• Position: Energy

Yards underneath a patch of land at Fort Benning, Ga., a layer of festering garbage from an old dump was producing methane gas.

The noxious--and potentially flammable--fumes were migrating underground to nearby facilities, so technicians installed vents, added propane to the mix, and burned the gas off. The energy dissipated and the process released greenhouse gasses into the atmosphere. Fort officials also had to pay for the propane.

Today, a small power station has been attached to the vents and is producing enough electricity to power about 250 homes.

The Defense Department has set lofty goals for its facilities when it comes to renewable energies. It wants to produce 3 gigawatts of renewable energy by 2025, with each service branch kicking in one more gigawatt. Each gigawatt can power about 250,000 homes.

Renewables are traditionally thought of as solar, wind and geothermal. The gas produced by microbes breaking down organic material buried in old garbage dumps is not in that category. It is a finite resource. But once the landfill is full and dirt is placed over it as a cap, it may produce methane for as long as a century, said Brad Hancock, director of federal programs at FlexEnergy, an Irvine, Calif-based company that makes the power station.

"If you look at the lifespan of a landfill being about 100 years, we can produce electricity basically the entire 100 years," Hancock said.

The amount of methane produced by a landfill placed on a chart looks like a perfect bell curve, he explained. For the first few years, very little gas is produced. Then it peaks for 20 to 30 years as it emits large amounts of high-quality gas. It then begins to tail off.

During the peak years, a regular turbine engine can be hooked up to the vents and electricity can be produced easily, although there will be so-called greenhouse gasses released, Hancock said.

The company's FlexPowerstation can generate electricity in the beginning and end stages of the landfill's lifespan, he said. "Our value is really on the wings out there in the years nobody else can do it," he said.

The power station marries two technologies and was the brainchild of company founder, Edan Prabhu, who was familiar with catalytic oxidizers, which are commonly used to break down such things as the compounds in chemical weapons when they must be safely disposed. The process does not release any substances into the air.

[ILLUSTRATION OMITTED]

Prabhu thought he could wed the oxidizer to a...