Small modular reactors, English Small Modular Reactor These are nuclear reactor designs known as SMR, abbreviated as "SMR". The IAEA generally uses this class for designs up to 300 MW of electrical power per unit, where a significant portion of the components can be manufactured in the factory and transported to the site as modules.
The word “small” refers to electrical power as well as physical size, and the word “modular” refers to the gradual installation of standardized parts and units. Not all SMR designs use the same technology.
How is it different from traditional large reactors?
A large nuclear power plant usually consists of a single or several high-capacity units. The SMR approach aims to install lower capacity units alone or as multiple modules, depending on need.
Suggested differences include:
- More factory production and off-site quality control
- Smaller single project financing needs
- Ability to add new modules as demand increases
- Different scale options for remote areas and small electrical systems
- More passive safety features in some designs
Whether these goals will be achieved in practice depends on the maturity of the design, supply chain and mass production volume.
Does SMR only produce electricity?
In addition to electricity generation, SMR designs are also evaluated for applications such as district heating, industrial process heat, hydrogen production or water purification. Suitability varies depending on the temperature level provided by the reactor and the energy needs of the facility.
What does passive security mean?
Passive safety systems can utilize physical effects such as gravity, natural circulation, and pressure differential to reduce the need for operator action, external electrical power, or active pumps when performing certain functions.
The term “passive” does not mean that a facility is risk-free. Design again requires detailed security analysis, licensing, operating procedures and emergency preparedness.
Key challenges of SMRs
- Cost and schedule uncertainty of first samples
- The economics of mass production cannot be proven without sufficient orders
- Licensing experience for new designs
- Management and personnel approach in multi-module facilities
- Fuel supply and waste management
- Physical security and safeguards
- Harmonization of standards between countries
Therefore, not only design goals but also construction, licensing and operating results of actual projects should be monitored in the SMR discussion.
Resources
- IAEA, Advances in Small Modular Reactor Technology Developments: https://aris.iaea.org/Publications/SMR-Book_2018.pdf
- IAEA, Technical Working Group on SMRs: https://nucleus.iaea.org/sites/htgr-kb/twg-smr/SitePages/Home.aspx
- IAEA, Platform on SMRs and their Applications: https://nucleus.iaea.org/sites/smr/SiteAssets/images/SMR_Platfrom_Booklet_WebVersion.pdf