In the not-so-distant future, cars could run on electricity, power plants on wind and solar energy, and city buses on zero-emission hydrogen fuel cells. But airplanes? Those just might run on coal.
Yes, coal. The U.S. Air Force wants to create a synthetic-fuel industry that, unless something better comes along, will mine America’s massive coal supply (we have more than a quarter of the world’s known reserves) and turn it into enough jet fuel for half its domestic operations to run on a 50/50 blend of synthetic and regular fuel by 2016. By the Air Force’s logic, it has no choice. It uses more fuel than all the other branches of the military combined, burning through 2.5 billion gallons of the stuff in 2007 alone—10 percent of the total used by the entire domestic-aviation fuel market—at a cost of $5.6 billion. And although oil prices have dropped in recent months, no one expects the relief to last indefinitely. Yet alternative fuels for aviation are hard to come by. The Air Force says it’s open to all sources of power for its fleet, but according to former assistant secretary of the Air Force William Anderson, petroleum, natural gas and coal are our only current options—and when you look at the U.S.’s resources, the choice is clear. “We’re not the largest holder of oil reserves, so that’s not a good option,” he says. “We’re not the biggest holder of natural gas. But we are the Saudi Arabia of coal.”
For Popular Science, I investigated the Air Force's plan to launch a domestic industry for coal-derived jet fuel.