ORNL is poised for innovation in the field of nuclear technology
Oak Ridge National Laboratory boasts an unusually broad array of research capabilities—from computing to biology to advanced materials. Surprisingly, many of these programs trace their roots to the laboratory's nuclear origins in the World War II Manhattan Project and the Cold War. Established out of a need to master the nascent field of nuclear science, ORNL designed, built and operated 13 research reactors in its first two decades of operation, establishing itself as one of the nation's premiere research institutions and making significant contributions to the scientific community's evolving understanding of nuclear science and technology.
Today, with renewed worldwide interest in nuclear power in general—and in a new generation of smaller, safer, more efficient reactors in particular—ORNL is poised to play a key role in a rebirth of innovation in the field of nuclear technology. "At its heart, ORNL is a nuclear laboratory," says Kelly Beierschmitt, head of the laboratory's Nuclear Science and Engineering Directorate. "We specialize in fields from fundamental nuclear physics to the disposal of used fuel and environmental cleanup." Between those endpoints, Beierschmitt's organization develops cleaner, more efficient nuclear fuels; creates computer simulations of safer, more efficient reactor systems; and produces isotopes for medical and research purposes.
An aficionado of nuclear history, Beierschmitt underscores the relative youth of nuclear science as a scientific discipline, noting that the neutron wasn't even discovered until 1932. Just three decades later, ORNL's High Flux Isotope Reactor was in operation, and to this day, some of HFIR's research capabilities are unique in the world. "HFIR and other early nuclear facilities were designed by scientists using slide rules in a little more than a generation," Beierschmitt says. "We should be humbled by the progress they made in that short period of time. If they could do that with slide rules, think about what we should be able to do with the computing resources we have today."
A new generation of technology
There are currently 104 nuclear power plants in the U.S., many of which are nearing the end of their useful lives, and utility companies are faced with making a huge investment to replace their generating capacity. "The 'do nothing' option does not exist," Beierschmitt says. "The decision to spend this money will have to be made, regardless of whether these plants are replaced with nuclear, coal, gas or renewable energy sources."
Beierschmitt is among a growing number of scientists who see nuclear power as a necessary part of the nation's energy portfolio. "Thirty or 40 years from now, I don't think industry will be able to depend exclusively on fossil fuel, because of both environmental factors and the volatility of energy markets," he says. Beierschmitt also contends that, while renewable energy sources, such as wind and solar can play a key role in meeting energy demands in some regions of the country, the relatively low output of renewables and restrictions related to weather, sunlight and energy storage will limit their contribution to the 21st century power grid.
Utilities are also faced with the retirement of thousands of aging coal-fired power plants. The void left by these plants could be filled by a range of clean energy options, including a new generation of nuclear power plants that employ one or more small modular reactors. Unlike traditional large-scale nuclear plants that generate up to a gigawatt of electricity, SMR-based facilities will use several small reactors to produce 300 to 500 megawatts of power—comparable to the coal plants they replace. These smaller reactors also don't require the huge capital investment of traditional nuclear plants, and their infrastructure needs, in terms of water and connections to the power grid, are similar to those of coal plants. Additionally, SMRs promise to improve reactor safety by incorporating passive systems that shut them down in the event of an emergency—without the need for external power or water.
A spectrum of expertise
As the U.S. and other nations approach this technological crossroads, ORNL is finding more opportunities to apply its experience with nuclear technologies in several key areas.
Reactor siting – ORNL has made considerable progress toward identifying potential SMR sites across the U.S. and defining variables important to siting decisions. Laboratory researchers combine sitespecific data with geographical information system mapping technology to produce highly detailed, computer-generated maps that display plant locations, infrastructure availability, population centers and much more. "The point of pulling all this data together is to build a resource that policy makers can use to test various scenarios," Beierschmitt says. "For example, if someone wants to replace 20 percent of the power generated by coal plants with nuclear power, how would that change the nation's energy mix? Where would these plants be located? How would this impact the use of water? On the other hand, what if they want to replace the existing, big nuclear plants with coal and gas plants, and how does that change the carbon footprint for the region? This technology allows us to play 'what if' games and simulate or even optimize how we might deploy nuclear power across the U.S."
Nuclear nonproliferation – The laboratory's Global Nuclear Security Technology Division has established a training center for the International Atomic Energy Agency and various governments to teach them how to operate and monitor nuclear power reactors in ways that are transparent to other nations and help to ensure that nuclear materials cannot be diverted for use in weapons. In addition to operating the training center, ORNL staff members provide expertise and advice on all phases of handling and processing uranium to countries and organizations all over the world.
Nuclear isotopes – ORNL produces nuclear isotopes for uses ranging from basic research to nuclear medicine to industrial applications. For example, the laboratory's ability to produce berkelium was critical to last year's discovery of element 117 by an international research team. ORNL also produces most of the world's supply of californium, an isotope used in cancer treatments as well as in industry for ensuring the quality of welds in bridges and buildings.
Reactor modeling and simulation – The laboratory recently began applying its high-performance computing capabilities to the nuclear sciences. Beierschmitt notes that ORNL is home to the Department of Energy's Consortium for Advanced Simulation of Light Water Reactors, an initiative to build detailed computer models of complex nuclear systems. "CASL will enable us to simulate how both existing and proposed systems behave on a very fine scale," he says. "Then we can validate the data produced by these models through experiments." ORNL's nuclear fusion research program is another beneficiary of supercomputer-based simulation and modeling. Beierschmitt notes that much of the next phase of fusion research will focus on applying high-performance simulation to the challenge of developing new materials that can contain the fusion reaction and translate its heat into electricity.
Storage and advanced fuel cycles – Until policy makers decide whether and how nuclear facilities should reprocess used nuclear fuel, it will continue to be stored at nuclear sites around the country. ORNL applies its simulation and modeling capabilities to address some of the questions surrounding long-term fuel storage. Existing models are based on several years' worth of real-world data. By combining this knowledge with detailed simulations of fuel stored under a range of conditions, researchers develop a better understanding of how used fuel ages and how to improve the safety of fuel storage facilities.
If nuclear fuel reprocessing is mandated, ORNL will provide its industrial partners with support for the technologies needed to handle and process used fuel. The laboratory will also provide computer models of fuel-handling processes to the Nuclear Regulatory Commission for use in licensing reprocessing facilities.
Materials science – ORNL applies its long-standing expertise in materials science to developing structural materials and accidentresistant fuels needed for use in advanced nuclear energy systems. The laboratory's advanced materials researchers test safe performance limits of materials in existing nuclear reactors, develop improved replacement materials, and conduct exploratory research on potential fuels and materials for use in the next generation of nuclear power plants.
The tools and the talent
As more attention is focused on nuclear power, more groups are looking to ORNL as a source of nuclear experience and expertise. Beierschmitt recalls that, on a recent day, representatives from the Australian Nuclear Science and Technology Organisation, the United Kingdom's National Nuclear Laboratory, the U.S. Navy's nuclear reactor program, and the Saudi Arabian government all passed through his office on their way to tour the laboratory's nuclear facilities and meet its scientists.
"People around the world are rediscovering Oak Ridge National Laboratory as a 'go-to' place for nuclear science and technology," Beierschmitt declares. "We are already playing a role in the renewal of nuclear science. We have superior tools and talented staff; we just need the opportunity to innovate. If we can have a fraction of the impact of the generation that came before us, that will be significant."—Jim Pearce