June 30, 2010 | 13
LINDAU, Germany—Quick: What do MRI machines, rockets, fiber optics, LCDs, food production and welding have in common?
They all require the inert, or noble, gas helium for their use or at some stage of their production. And that helium essentially could be gone in less than three decades, Robert C. Richardson, winner, along with Douglas Osheroff and David Lee, of the 1996 Nobel Prize in Physics, said at the 60th annual Nobel Laureate Lectures at Lindau today. “Once it is released into the atmosphere, say, in the form of party balloons, it is lost to the Earth forever—it is lost to the Earth forever ,” he added.
Helium molecules, produced by the sun’s energy, naturally make up only about five parts per million of the Earth’s atmosphere. The rest of the gas—the second lightest element in the universe after hydrogen—escaped our planet 4.7 billion years ago.
The U.S. holds vast majority of the world helium stocks, managed by the U.S. Bureau of Land Management; the gas sits underground in natural salt domes atop granite in the Great Plains. Congress passed a law in 1996 dictating the sale of all U.S. stocks by 2015 to compensate the government for its investment in the helium and its storage. A 2000 study conducted by the National Research Council concluded that a helium surplus would exist for the foreseeable future.
Soon after that report, however, helium usage skyrocketed, as the gas yielded many benefits for industry and medicine. In a January 2010 report for the National Research Council, “Selling the Nation’s Helium Reserve,” Richardson and committee cochair Charles G. “Chip” Groat, a University of Texas at Austin geologist, described the pitfalls of the current U.S. strategy.
Many industrial processes rely on helium. In 2007, the most recent year for which figures are available, said Richardson, 28 percent of helium use went to cryogenics for MRI and nuclear magnetic resonance machines—nearly all of it for clinical purposes (scientific cryogenic uses are only 3 percent of that total). Some 26 percent of helium is used in pressurizing and purging of rockets; another 20 percent for welding; and 13 provides inert atmospheres in the production of fiberoptics, LCDs and food.
Richardson recommends several steps to ensure helium availability in the future. First, prices should be raised by a factor of 20. “The world price of the gas is ridiculously cheap,” said Richardson, as a result of the U.S. policy. Second, substitutes can replace helium for certain areas—argon can be used in welding, for instance. Last, cryogenic helium users should recycle the gas in closed systems; already, MRI machines use such systems for their powerful superconducting magnets.
“That which God has taken 4.7 billion years to create will be dissipated in a little more than 100 years,” noted Richardson. “One generation doesn’t have the right to determine availability forever.”
Learn more about the Lindau meeting at Scientific American‘s sister publication Nature, the international journal of science, and a special Web site featuring Lindau blogs, organized by Nature and Spectrum der Wissenshaft, Scientific American ’s German language edition. A slide show, Discoveries 2010: Energy, covers another Lindau initiative, a museum exhibit on energy sources.