China
Africa
Explore chapters and articles related to this topic
Nuclear energy
Published in Peter M. Schwarz, Energy Economics, 2023
Canada uses a different technology known as the Canada Deuterium Uranium (CANDU) reactor. It uses deuterium oxide (heavy water) as a moderator and coolant and natural, unenriched uranium as a fuel. With modification, it can also use enriched uranium, mixed fuels, or even thorium, a slightly radioactive element more abundant than uranium but more expensive from which to extract useful energy. CANDU’s cost declined rapidly after the first plant that began operations in 1957. They began to build larger plants between 1971 and 1986 and experienced modest 4% annual cost escalation.
Project Initiation
Published in Kurt Heinze, Cost Management of Capital Projects, 2017
How about nuclear accidents? The consequences of an accident vary with the design of the station. The CANDU reactor for example uses heavy water (deuterium) for both, moderator and cooler. Even though more expensive, it is considerably safer than fast reactors which use enriched fissile fuel and graphite moderators. And yet, in the eyes of the public, all nuclear stations pose the same danger. We therefore need to be aware of the difference between perception and actual statistical data of risk involved.
Preliminary considerations: reactor types and characteristics
Published in Peter R. Mounfield, World Nuclear Power, 2017
The CANDU reactor offers a number of advantages: on-load refuelling at full power has enabled the design to lead the world in terms of load factor and reliability; the use of natural uranium results in lower fuel fabrication costs than for PWRs, BWRs and AGRs, which require expensive fuel enrichment facilities. The use of natural uranium makes CANDU reactors virtually inflation proof once they are built. More parts, more processing, more tubing, more pellet-grinding, more hardware and more labour are involved in producing a tonne of LWR fuel than in producing a tonne of CANDU fuel. The use of pressure tubes for fuel in the reactor core allows the coolant to be pressurized without the need for a large steel or reinforced concrete pressure vessel; it is economically competitive with most other proven reactor types for plants of about 500 MWe and over; it is an efficient producer of plutonium; it does not have a high excess of reactivity as do reactors using enriched fuel, and this helps to reduce the likelihood of a major power excursion.
Transient System Thermal-Hydraulic Assessment of Advanced Uranium- and Thorium-Based Fuel Bundle Concepts for Potential Use in Pressure Tube Heavy Water Reactors—I: Two-Channel Analyses
Published in Nuclear Technology, 2021
S. Wang, T. Beuthe, X. Huang, A. Nava Dominguez, A. V. Colton, B. P. Bromley
Natural uranium (NU) is the main fuel used currently in conventional pressure tube heavy water reactors (PT-HWRs). Thorium, as an alternative fertile nuclear fuel, is far more abundant in the earth’s crust.1 PT-HWRs such as the CANada Deuterium Uranium (CANDU) reactor (see Figs. 1 and 2) feature a unique design that makes them well suited to use advanced uranium-based and thorium-based fuels.2,3 PT-HWRs utilize compact, self-contained fuel bundles and are able to reposition these bundles in the reactor while operating at full power. The excellent neutron economy of PT-HWRs through the use of heavy water as moderator and as coolant, as well as the ability to carry out online refueling, provides PT-HWRs with a high degree of operational flexibility with regard to alternative fuel concepts. Therefore, it is possible to consider the use of a variety of advanced uranium-based and thorium-based fuel concepts for potential use in existing PT-HWRs including CANDU reactors.4 The use of advanced fuels could help extend nuclear fuel resources while also achieving improvements in operational safety margins in PT-HWRs.
Mechanism of the Initial States of a Bubble Formation and Departure from a Heated Surface in a Subcooled Flow
Published in Nuclear Science and Engineering, 2021
Maryam Medghalchi, Nasser Ashgriz
The CANada Deuterium Uranium (CANDU) reactor is a Canadian-developed pressurized heavy water nuclear reactor. CANDU reactors comprise a series of horizontal fuel rods inside a high-pressure subcooled flow. The ability to model the nucleation and heat transfer processes in such reactors is essential for their safety as well as for their efficiency. Since full computational simulation of the whole reactor is not feasible, the reactor is simulated using subchannel models, which basically lump certain physics into one large grid. This type of simulation may not be able to realize certain important heat transfer processes that occur, especially during the initial periods of the bubble nucleation.
Steady-State Subchannel Thermal-Hydraulic Assessment of Advanced Uranium-Based and Thorium-Based Fuel Bundle Concepts for Potential Use in Pressure Tube Heavy Water Reactors
Published in Nuclear Technology, 2021
A. Nava-Dominguez, S. Liu, T. Beuthe, B. P. Bromley, A. V. Colton
Thorium is an abundant fertile nuclear fuel that could be used in reactors to complement, augment, or replace the use of uranium. Pressure tube heavy water reactors (PT-HWRs), such as the CANadian Deuterium Uranium (CANDU) reactor (see Fig. 1), have excellent neutron economy and operational flexibility due to the use of heavy water as a moderator and as a coolant and due to an online refueling capability. These features make PT-HWRs ideally suited to utilize various advanced uranium-based and thorium-based fuels.