By 2011, the entire U.S. Air Force fleet should be running off a domestically produced blend of half synthetic, half petroleum-based fuel. Of course this move is spurred in large part by a desire to wean itself from foreign oil.

In 2006, the Air force sucked up about 2.6 billion gallons of aviation fuel, costing more than $5.7 billion.

This week, a C-17 Globemaster cargo aircraft, a commonly used plane in Iraq and Afghanistan and the military's biggest user of fuel, flew for the first time with a coal-derived blend of fuel.

The blended jet fuel, or synfuel, produced 1.8 times more carbon dioxide between production and consumption as jet fuel from oil, but the Air Force seems to think the difference could be captured during production.

Commercial carbon sequestration isn't to the point yet where we can actually capture all carbon dioxide emissions released during production, and even if that technology quickly evolves, this move still means the dirty and environmentally hazardous process of coal mining would continue in the United States.

This may not be the right move for the environment or for the government's coffers, given other fuel alternatives being researched.