A report by the International Atomic Energy Agency (IAEA) on ‘Advances in Small Modular Reactor Technology Developments’ says the Steenkampskraal Thorium Limited (STL) HTMR-100 thorium reactor is suited to servicing the needs of isolated geographical areas and is a perfect fit for clients who want to progressively extend their generating capability. The unique safety characteristics make it possible to introduce and construct these plants to non-nuclear countries.
The report says the high-temperature small modular reactor (HTR SMR) comes into its own right when various combinations of electricity, process heat and water desalination are considered and holds great promise for the long-term economics of users.
Steenkampskraal thorium mine in the Western Cape.
“Preliminary capital and operating cost studies indicate that this flexibly of the HTMR-100 provides the most efficient energy to isolated communities and industries. It is well suited to deployment in developing countries with its affordability and Gen IV safety characteristics,” the IAEA says.
“The HTMR-100 (High Temperature Modular Reactor) pebble bed reactor is a gas cooled reactor, graphite moderated and cooled by forced helium flow. The existing design of the module is to produce high-quality steam which is coupled to a steam turbine/generator system to produce 35MW of electric power. The steam can be used in a wide range of cogeneration applications.”
The IAEA report continues: “The reactor is also suitable to provide direct high-temperature energy for process heat. The design of the reactor is based on proven technology and therefore no new basic technology development is needed. The size of the reactor and the fuel cycle were chosen to simplify the design and operation of the module. The approach to small intrinsic safe modular units ensures continuous production, easy road transportability, skid-mounted sub systems, a wider range of manufacturers, fast construction and an enhanced licensing process.”
Target Applications
The HTMR-100 is capable of supplying electric power to any distribution grid and to standalone or isolated electricity users. It can be deployed as single modules or multi-module plants as well as medium temperature process heat applications. The HTMR-100 is a perfect fit for clients who want to progressively extend their generating capability. The unique safety characteristics make it possible to introduce and construct these plants to non-nuclear countries. First-world countries that want to utilise their stock of Plutonium for peaceful applications are also markets for HTMR-100 reactors, the report notes.
Site and Plant Layout
The HTMR-100 is configured to simplify the construction of the various buildings and to ensure easy installation of the reactor, steam generator and handling of spent fuel. The proposed plant layout aims to protect safety important functions while simplifying operational and maintenance tasks. The plant layout allows for the addition of multiple reactors (and associated equipment) in a compact multi-module fashion, the report states.
Reactor building
The report continues: “The reactor building contains the safety equipment that provides the necessary functions for the safe shutdown of the reactor under all design basis conditions. The reactor building is partially submerged below ground level such that the reactor and steam generator cavities are completely protected against postulated external threats.”
“The depth can be further adapted to suit the geological conditions of the specific site to provide for the necessary level of seismic protection. The reactor building, electrical building and auxiliary buildings are connected by means of underground tunnels, providing protection for interlinked services and, it also ensures that spent fuel is never brought above ground level. Provision is made for the storage of all spent fuel produced during the operating life of the plant.”
“The reactor building is seismically designed to withstand a design basis earthquake (DBE) and together with the spent fuel storage bunker, is the only safety related building structure of the HTMR-100.”
Design and Licensing Status
“Conceptual design is in an advanced stage. The core, neutronic, thermo-hydraulic and heat transfer analyses are being done to optimize the performance and verify the safety analysis. Nuclear Regulator engagement is planned for 2017 with the aim of commencing the pre-assessment for licensing in order to reach design certification status at the end of the Concept Phase,” the report concludes.
Issued on behalf of: Steenkampskraal Thorium Ltd
Email: david.boyes@thorium100.com
