|
|
| Fig. 1: The Oak Ridge National Laboratory in Eastern Tennessee. (Source: Wikimedia Commons) |
In the wake of the 2016 Paris Climate Agreement, international attention on low-carbon and carbon-free energy sources has rapidly grown. By 2019, increased investment in solar and wind technology over the previous nine years had driven down costs for these energy sources by 88% and 69%, respectively, with China pouring $91 billion into renewables investments in 2018 alone. [1]
These shifts, while helpful in addressing the climate crisis, are leaving nuclear power far behind. Stagnating investment in nuclear technology has increased both construction times and costs, and nuclear power generation can now cost 3 to 5 times more per megawatt hour than onshore wind, which can be produced for as little as $26 per MwH, and solar, which costs between $36 and $44 per MwH. [1] As a result, developed countries' nuclear capacity is projected to first dwindle and then rapidly decline over the next two decades, undermining attempts to meet international emissions goals. [2]
In response, several countries have begun exploring new developments in nuclear technology that could help them close emissions gaps by reducing costs. [3] In 2021, the French, British, and American governments all announced partnerships with manufacturers and researchers for producing cheaper components that could be used in small modular reactors, or SMRs, which advocates argue are safer and more efficient than traditional plants. [3] Over a dozen countries currently have programs focused on developing SMRs, and as this research continues, SMR technology manufacturing will become easier, faster, and more standardized, encouraging the use of 3D printing technology for the rapid prototyping, development, and production of SMR components. [4]
3D printing, which is the production of a physical object from a digital model, was first used on an active reactor in 2017, when Siemens installed a 108-mm water impeller at Slovenia's Krcko plant. Efforts to use 3D printing in all parts of the nuclear power generation process have since accelerated, as increased federal and private funding aligns with rapidly-improving technical know-how. [5] In 2020, research at Tennessee's Oak Ridge National Laboratory (see Fig. 1) led to several crucial breakthroughs that demonstrated the success of a wide array of 3D-printed reactor components, one of which was installed in the Browns Ferry reactor in Alabama in September of last year, and brought researchers closer to perfecting the first 3D-printed nuclear reactor core, which the Laboratory believes will be operational by 2023. [6]
Using 3D-printed components in existing nuclear facilities is an ultra-low cost means of extending service lifetime for countries with nuclear infrastructure that would otherwise have to be shut down, while also unlocking massive new opportunities for the rapid deployment of SMRs in novel settings. ORNL's research since 2014 has centered on innovating the use of fully ceramic microencapsulated (FCM) fuel in fluoride-salt-cooled high-temperature reactors instead of light water reactors. Notably, tristructural isotropic (TRISO) particles, which have historically been used in graphite matrices, are used in silicon carbide (SiC) matrices for FCM fuel. TRISO particles are being substantially re-engineered through ORNL's new research, which proposes a fuel kernel diameter of 500-μm, a porous carbon buffer with a thickness of 100 μm, two 40-μm pyrolitic carbon layers, and a 35-μm outer SiC layer. [7] In the wake of ORNL's announcement, several nuclear startups have licensed the Laboratory's 3D-printed design as they pursue even cheaper manufacturing processes. Seattle-based Ultra Safe Nuclear Corporation is at the forefront of these efforts. In February 2022, the firm announced that it had successfully implemented Oak Ridge's binder jet printing technology to produce an efficient core design consisting of irregularly-arranged nonagonal fuel assemblies that uses FCM fuel. This new technique, it reported, could allow it to produce reactors for less than $100 million, enabling the first-ever privately-funded commercial deployment of an SMR in Ontario. [6] These purported technological breakthroughs, though still relatively unproven, could be a first step toward a new era of cheap, highly-efficient nuclear power that finally sees nuclear energy make good on its elusive but truly enormous promise.
© Francisco Nodarse. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
[1] M. Dunai and G. De Clercq, "Nuclear Energy Too Slow, Too Expensive to Save Climate," Reuters, 23 Sep 19.
[2] G. De Cleercq, "IEA Rings Alarm Bell on Phasing Out Nuclear Energy," Reuters, 27 May 19.
[3] L. Alderman and S. Reed, "Europe Revisits Nuclear Power as Climate Deadlines Loom," New York Times, 29 Nov 21.
[4] "Nuclear Technology Review 2021," International Atomic Energy Agency, September 2021.
[5] J. Conca, "3D Printing Has Entered the Nuclear Realm," Forbes, 9 May 20.
[6] P. Patel, "How to Make an Impossible Nuclear Reactor (3D Printer Sold Separately)," IEEE Spectrum, 2 Feb 22.
[7] J. Powers, "Fully Ceramic Microencapsulated Fuel in FHRs: A Preliminary Reactor Physics Assessment," Trans. Am. Nucl. Soc. 111, 1196 (2014).
