On the issue of the enhanced safety and cost efficiency provided by small and modular (SMR) reactors, making these more suitable for Asian countries, various research has shown that SMRs, essentially by virtue of their design, provide increased safety by eliminating many of the factors that provoke accidents.
This has been borne out by the International Atomic Energy Agency (IAEA) which has said that the small thorium based gas-cooled high temperature (STGR) nuclear reactors are totally safe with a core damage frequency (CDF) of zero. This is further underlined through market practice, where it is seen that insurance companies are more willing to provide insurance to STGR reactors.
Acccording to the IAEA, the safety of a nuclear reactor is most dependent on its design. In the traditional large water cooled reactors, the safety systems have to bring the reactor to a safe shutdown when any accident takes place, which is a highly expensive and complicated system.
The IAEA further says that safety is also a matter of fuel design and how the nuclear fission reaction is controlled in the reactor core. According to the agency, modular high temperature gas cooled reactors (MHTGR) being small in size, with predesigned geometrical restrictions and limitations of the reactor and fuel elements, are inherently safe owing to their design features. Besides, their power density is low, while minimal fuel is available in the reactor. Moreover, the chances of core damage of the MHTGR are nil, according to the IAEA.
Among the Asian nations, taking the case of India, the IAEA has specifically pointed out that small thorium based gas cooled high temperature reactors in the 20MW-40MW range are completely safe with a core damage frequency rate of zero. The agency has reiterated that such SMRs merit introduction in India not only for their innovative technology, but also for other economic benefits of the STGRs. An IAEA report says that “for 10,000 STGRs in India, the combined core damage frequency (CDF) will still be 0.”
It is a known fact that India has plentiful thorium reserves to fuel STGR reactors. Moreover, there are other factors which make this technology an attractive proposition for the country. These include faster delivery time, the feasibility of speedy local manufacturing as well as much lower costs as compared to conventional nuclear power plants. They are the ultimate in safety, security and efficiency and do not require any earmarked no-habitation zone around the plant.
Moreover, these STGRs can help provide cheap electricity and drinking water, gamma rays for food and agriculture produce preservation and for application in nuclear medicine to combat diseases like malaria, Zika and dengue. Most of all, from the perspective of climate change such SMRs would go towards helping phase out coal-fired thermal power plants.