The licensing of SMRs will be affected by the Fukushima accident in the same way as for large reactors. Regarding licensing status and regulatory issues relevant to SMRs, the analysis of recent publications leads to the following observations: [7]

• The SMRs available for deployment, which are the CANDU-6, the PHWR, the QP-300, the CNNP-600, and the KLT-40S, have already completed the licensing procedures in the countries of origin. The CANDU-6 and the QP-300 have also been licensed and deployed in countries other than the country of origin.

• For advanced SMR designs, three of them are in a formal licensing process in Argentina, China and the Republic of Korea, and several others are in pre-licensing negotiations in the United States and India, see Table E.1.

Regulatory issues and delays regarding SMR licensing may occur due to the following main reasons:

• Some advanced, water-cooled SMR design concepts incorporate novel technical features and components targeting reduced design, operation and maintenance complexity which will need to be justified by the designers and accepted by the regulators. There is currently no regulator which has approved such designs for construction.

• Non-water-cooled SMRs may face licensing challenges in those countries where national regulations are not technology neutral, e. g. they may be based on established water-cooled reactor practice. A lack of regulatory staff familiar with non-water-cooled reactor technologies may also pose a problem in some countries.

• Some of the advanced SMR design concepts provide for a long-life reactor core operation in a “no on-site refuelling mode”. The regulatory norms providing for justification of safety in such operation modes may be not readily available in national regulations.

Government support for licensing of selected, advanced SMRs could help overcome the corresponding delays.

Another important set of regulatory requirements concern the ability of SMRs to resist nuclear proliferation. All advanced light water PWR SMRs use conventional LEU fuel and most of the PWR SMR designs use the same fuel as large PWRs. However, particular attention should be paid to the non-proliferation potential of some heavy-water or liquid-metal cooled designs, especially if they are intended to be deployed in politically unstable areas. The IAEA has an on-going activity on the options of incorporation of intrinsic proliferation resistance features in NPPs with innovative SMRs, and the report is expected to be published soon.

Conclusions

A principal conclusion of this study is that SMRs have a significant potential to expand the peaceful applications of nuclear power by catering to the energy needs of those market segments that cannot be served by conventional NPPs with large reactors. Such segments could be:

• Niche applications in remote or isolated areas where large generating capacities are not needed, the electrical grids are poorly developed or absent, and where the non-electrical products (such as heat or desalinated water) are as important as the electricity; [8]

• Replacement for those decommissioned fossil-fuelled combined heat and power plants, where the SMR power range seems to better fit the requirements of the currently existing heat distribution infrastructure;

• Power plants in liberalised energy markets or those owned by private investors or utilities for whom small upfront capital investments, short on-site construction time (with the accordingly reduced cost of financing), and flexibility in plant configuration and applications matter more than the levelised unit electricity cost.

It should be noted, however, that none of the smaller reactors has yet been licensed for these applications and there remain both development challenges to overcome and regulatory approvals to obtain before deployment, especially in light of the recent accident at Fukushima.

The present study has found no situations where NPPs with SMRs could compete with the NPPs with state-of-the-art large reactors, on LUEC basis. However, it also found that SMRs could be competitive with many non-nuclear technologies in the cases when NPPs with large reactors are, for whatever reason, unable to compete.