Part 2 of 2 Parts
      NuScale is further along in the approval process than other, more unconventional reactor designs such as the sodium-cooled fast reactor. This reactor creates more fuel than it consumes. Eight countries have built versions of this reactor over the past sixty years at a cost of over one hundred billion dollars. None of these prototypes have proven to be reliable enough to produce electricity competitively. The U.S. has decided on this design for the Versatile Test Reactor at a cost of up to six billion dollars.
     Other startup vendors are considering two other new designs aside from sodium-cooled fast reactors. The first type is molten salt reactors. Only a few of this type of reactors have ever been constructed and operated. They use either fluoride or chloride salts. These are often mixed with lithium or beryllium. The second type are high-temperature gas reactors with helium as a coolant and graphite as a moderator. The U.S. built and operated two of these power reactors between the 1960s and the 1980s. China, Germany and Japan have all built and tested high-temperature gas reactors.
      Another major challenge for these new reactors is that they must use new fuels which must be licensed as well as produced, managed during use, and stored and disposed of when spent. Some of these new reactor designs depend on the use of nuclear fuels that require higher enrichments of uranium. The U.S. has little capacity to produce such fuel. Higher enriched uranium fuels raise concerns about nuclear proliferation. They would require international safeguards.
      Even if these fueling problems could be solved, novel reactor designs also face significant construction challenges. Many of the new designs rely on the availability of adequate sites and efficient construction to achieve profitability. The nuclear industry has long suffered from long construction times and major cost overrun. Since 1980, the construction time required to construct most reactors in the U.S. has been over ten years and costs have skyrocketed. New reactor builds in Europe have had similar problems, The French EPR reactor design has experienced multiple delays and huge cost overruns in both France and Finland. These megaprojects face challenges in program management and quality control. Regulatory issues often result in significant delays.
     The U.S. is not an outlier with respect to these issues. Nuclear reactors around the world are aging and most are not replaced when they are close. In 2019, six reactors began operating and thirteen reactors were permanently shut down. The average age of the four hundred and eight operating power reactors in the world is thirty-one years. Eighty-one of them are over the age of forty one years.
     For all these reasons, nuclear energy cannot be a near or even middle term solution to climate change. Considering how many economic, technical and logistical hurdles stand in the way of constructing safer, more efficient and cost competitive reactors, nuclear energy will not be able to replace other forms of electrical generation quickly enough to achieve the levels of carbon emission reduction necessary to prevent the worst effects of climate change.
     Innovations in reactor designs and nuclear fuels still deserve significant research and government support. In spite of its limitations, nuclear power still has some potential to reduce carbon emissions. Rather than placing unfounded faith in the ability of nuclear power to seriously mitigate climate change, the focus needs to be on the real threat of the changing climate. We need strong government support for noncarbon-emitting energy technologies that are ready to be deployed today, not ten to twenty years from now because we have run out of time.