Small modular reactors (SMRs) can be said to be one of the future trends of the fourth generation of nuclear energy. They are cheaper and more mobile than traditional reactor designs. They have attracted the attention of many countries and enterprises. Recently, in addition to Rolls-Royce, the US Department of Defense and Japan's Mitsubishi Heavy Industries all continue to promote the progress of SMRs and hope to make breakthroughs around 2030.
SMR technology is based on the reactor of a nuclear submarine. Compared with a traditional reactor, size and scale are naturally smaller. Basically, the hoped is that a nuclear reactor of less than 300MW can be built, and even be manufactured on the same scale as a car, while factory manufacturing technology introduced to reduce the cost of nuclear power. Due to its small scale, it can also be used in special applications such as oil exploration and military bases, and be installed underground, on ships or at sea.
Rolls-Royce sees SMRs as a potential source of revenue and focused on SMRs far more than previous jet or diesel engines. Chairman of Rolls-Royce Small Modular Reactors, Paul Stein, stated he hoped his coompany’s SMR design could be approved by UK regulators by mid-2024 and power the grid by 2029.
The British government asked the nuclear regulator to start the approval process in March and in November backed Rolls-Royce's $546 million (about NT$15.9 billion) financing to develop Britain's first SMR. In addition, Rolls-Royce is also expected to build and operate 10 to 15 SMRs in the UK, which is estimated to bring in a value of 52 billion pounds by 2050, with a total export value of 250 billion pounds and an oppurtunity to create 40,000 new jobs.
The British government hopes to reduce dependence on fossil fuels and reduce carbon emissions through nuclear energy, which will be able to supply a quarter of Britain's electricity in the future.
Across the pond, the United States also sees small nuclear power as a priority. The U.S. Department of Defense announced that the Strategic Capabilities Office will build and demonstrate a small, mobile nuclear reactor capable of delivering 1 to 5 MW of capacity within three years.
The Project Pele microreactor will be assembled and tested at the Idaho National Laboratory (INL) under the Department of Energy in the future, which will be the first fourth-generation nuclear reactor to be built and generate electricity in the United States. This technology is expected to assist the military with high mobility and high energy demand in the future.
What about the design of Project Pele? No decision has yet been made. Entering a two-year design phase in 2020, it is only known that it includes Virginia-based BWXT Advanced Technologies and Maryland-based X-Energy. Both companies use high-content, low-enriched uranium tristructurally isotropic (TRISO) pellet fuel to develop high-temperature gas-cooled microreactors that are stronger, more heat-resistant, and generally more suitable for transport than conventional nuclear fuel rods.
The advantage of SMRs is their modular design, making them easy to transport and install. Mitsubishi Heavy Industries' micro reactor is 3 meters high, 4 meters wide, and weighs less than 40 tons.
Size and scale are so small that they can be installed underground to reduce the risk of accidents or used for space exploration missions. Estimated maximum output power is 500 KW. Once approved by Japan and other governments, Mitsubishi plans technology commercialization of its SMR as soon as the 2030s.