Page 44 - Energize December 2022

TECHNICAL

steam generating plant (boilers), but
retains generating plant (turbines and
generators) and other electrical plant.
The retrofit program is being pursued
actively by China.

Replacement and retrofit of inland plant
depends on the development of reactors
which do not use water for cooling of the
reactor i.e., HTMR, pebble bed, etc.
New build programmes
There are numerous new build
programmes worldwide. Most notable is
China with an estimated 150 new NPPs
Figure 5: Construction of pebbles (Nuclear Street)
planned, India with 20 new NPPs, and the
UK with a planned additional 24 GW of
layer of silicon carbide; and an outer layer of pyrolitic carbon. These layers provide the new NPPs. Notable also is Holland with
structural support necessary to endure irradiation during the fission process. Thousands two new NPPs planned, and France with
of these TRISO particles are then embedded in a graphite matrix and formed into a 16 new NPPs. South Africa still has two
sphere. An outer layer of graphite is then added to fully form the 60 mm fuel sphere. new NPPs in the IRP2019 with a combined
The first successful application of the gas cooled pebble bed design is the Chinese capacity of 4096 MW.
HTR-PM, a two PB reactor unit with a capability of 200 MWe that has been delivering Australia, Italy, Germany and New
power to the grid since December 2021. China has plans for a larger unit, with six PB Zealand all have anti-nuclear policies that
reactors driving a single 600 MW turbine. prohibit the building of new nuclear plant
South Africa has a long involvement with the gas cooled pebble bed reactor. The and are all stuck with a political decision
technological root of both the South African and the Chinese PBMRs is the German that cannot easily be reversed. No politician
high-temperature, gas-cooled reactor (HTGR) developed at the government’s Jülich will ever admit to being wrong, even if
6
research centre. The South African project was officially discontinued in 2009, but the changed circumstances provide an escape.
PBMR concept has been pursued by private companies since then, with several versions It is important to note that “undeveloped
emerging, including a thorium fuel-based version. countries” such as India and China, have
not followed the trend to reduce nuclear,
Thorium SMRs and have an active NP build program,
Several of the above SMR technologies have been adapted to use thorium as a fuel and while developed countries like Russia and
there are a number of SMRs using the thorium cycle under development worldwide, South Korea have well established nuclear
mainly in the Nordic countries but in South Africa as well. manufacturing industries.
4,5
A very good reference on the state of SMR development is the IAEA publication
“Advances in Small Modular Reactor Technology Developments” References
https://aris.iaea.org/Publications/SMR-Book_2018.pdf 1. MIT: “The Future of Nuclear Energy in a
Carbon-Constrained World”, MIT energy
initiative, 2018.
The micro reactor 2. P Carajileskov: “Construction time of PWRs”,
A team at Brigham Young University has announced the development of a fully INAC, 2011.
transportable micro molten salt reactor with an output of 10 MW. Having the molten 3. BYU: “BYU profs create new nuclear reactor
to produce nuclear energy more safely”,
salt reactor is the equivalent of having a silicon chip. We can have smaller, safer, cheaper https://news.byu.edu/byu-profs-create-
reactors and get rid of those problems. 3 safer-system-to-produce-nuclear-energy
4. Dr A Cilliers: “Nuclear power - unaffordable,
Nuclear power application or lowest cost energy available?”, News24.
com, 09 Nov 2017.
There are three areas of application for new nuclear in the expansion and 5. M. Hussain, et al: “Advances in
decarbonisation programme. Small Modular Reactor Technology
Developments”, IAEA, 2018.
• New plant: Plant established as an addition to existing capacity at new site or as 6. S Thomas: “Demise of the Pebble Bed
additional on an existing site Modular Reactor”, Bulletin of the Atomic
• Replacement: New plant replaces existing coal or gas fired plant, either at existing Scientists, 2009.
site or at new site. At an existing site, auxiliary electrical plant such as transformers
are retained. Send your comments to
• Retrofit: The new nuclear plant replaces part of the existing thermal plant, such as rogerl@nowmedia.co.za

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