Carbon-fiber manufacturing could boost coal

A 3-D printed, carbon-fiber submersible made mostly from coal. (Dept. of Energy photo)

As more utilities switch from coal to cheaper, cleaner energy sources, America's huge coal reserves are increasingly untapped. But scientists are experimenting with new uses for coal, and while "no one expects the research to revive all the coal-mining jobs that disappeared in recent years, experts say new sources of demand are emerging for the carbon-rich rock, from battery electrodes to car parts to building materials," Tim Loh and Patrick Martin report for Bloomberg.

Probably the biggest potential use for coal right now is in creating carbon fiber, a stiff, strong, and ultra-lightweight material that has been widely used for aircraft and other items for years. The lion's share of most carbon fiber is made from a polymer resin called polyacrylonitrile, with a dash of petroleum pitch. But Mitsubishi has used coal for decades to create carbon fiber, so it's possible to change the formula to be mostly coal.

At the Oak Ridge National Laboratory in Tennessee, researchers used coal and a 3-D printer to create a 30-foot-long submersible to show what carbon fiber made from coal can do. "At the Oak Ridge lab, the 3-D printing techniques for the carbon-fiber sub hull helped reduce production costs by 90 percent and shortened manufacturing time from months to days, according to the Department of Energy. Improved design and building techniques encourage more use of carbon fibers, which could increasingly come from coal," Loh and Martin report.

Bloomberg graphic; click to enlarge

Most of America's coal is still used for electricity, but it's in decline. Coal accounts for 30 percent of the power mix used by utilities today, down from 50 percent in 2008. Correspondingly, the number of miners in the U.S. fell 40 percent to about 50,000 in the same time period. Oak Ridge researcher Edgar Lara-Curzio says "Coal for power generation is going to continue to decrease. Here is a chance for us to pay back all these coal communities that have sacrificed for so many years to give us cheap electricity."