Page 48 - Energize November 2022

TECHNICAL

would develop in future years. Thorium rough terrain, to reach a remote An African network
is widely distributed around the world, power station. If need be, fuel balls It would be good to consider an
even though in many countries there are could be airlifted to an HTMR-100, if African network of HTMR-100 reactors,
only very low concentrations. Thorium is for example, floods had cut road and distributed over many countries. Modern
an ideal fuel because it cannot be used in rail links. It is also easy to stockpile communication technology makes it
any way for nuclear weapons, and high- enough fuel on site to last for a year possible to link any number of reactors
level nuclear waste from a thorium reactor or two. together via the Internet, no matter
is more benign than that produced from where they are. Such interlinking can lead
uranium. The HTMR-100 can also use Nuclear waste to great mutual collaboration in that, for
plutonium or even types of nuclear waste For some years projects examining example, temperatures and pressures
in its fuel, making it exceptionally versatile. the recycling of spent fuel have been on all reactors can be monitored and
The gas-cooled technology of the HTMR-100 undertaken. Spent fuel is a valuable compared at a central point. A central
was chosen because it allows one to build resource and is not merely nuclear team would issue reports and warnings
a reactor anywhere – even where no large waste, as some like to portray it. of any possible deviations from expected
body of water exists. Atoms such as plutonium certainly normal operations. Teams of inspectors,
can be ‘burnt’ in a reactor, as can the or maintenance teams, would respond to
Replacing decommissioned unused portions of the original fuel. any reactor, thereby cutting maintenance
coal-fired plants The HTMR-100 can be used in this costs by reducing the number of teams
One cannot easily predict how the political manner should such a requirement on standby in each country.
landscape will affect electricity production arise in the future.
in the future. There have been intentional Conclusion
moves away from coal-fired power Looking ahead, ‘in the light of the current
plants in some countries. In many cases, darkness’, we can all see the urgent need
undoubtedly, when coal plants get old and to reduce load shedding. And not just in
are ready for decommissioning, they will be South Africa: Europe is now threatened
replaced by newer technologies. However, with the real prospect of load shedding
since all the electrical interfaces are already in the coming winter. Like Europe, we can
in place at existing power stations, they now see that nuclear power, whether as
would be good sites for a set of SMRs. conventional reactors or small modular
The HTMR-100 is designed for a 60- reactors, can help us all to triumph over
year lifespan, so all financial calculations the challenges of tomorrow and give us
should be carried out with that in mind. By all a brighter future.
comparison, wind and solar systems are Figure 3. A fuel ball for a HTMR-100
typically designed for a 20-year lifetime. reactor. The reactor would use about 125 Send your comments to rogerl@
Note too, that the HTMR-100 reactor of these 60 mm diameter fuel balls during nowmedia.co.za
each day of operation.
site is designed to store about 40 years’
worth of spent fuel. This is done in on-site
bunkers. This is to accommodate legislation
which might require that a number of years’
worth of fuel be stored locally pending the
final repository decisions that a country,
which would purchase this reactor, might
make.
A major advantage of the HTMR-100
is that it does not need to be stopped
for refuelling. Fuel balls are added and
extracted continuously, without any
alteration to the reactor’s operational
functionality. Fuel balls are very robust and
can take some rough handling: which is
somewhat different to the large metal-tube
assemblies typically used in a conventional
pressurised water reactor (PWR). This
means that fuel balls can be transported
over long distances, and over potentially Figure 4: A model of an HTMR-100 reactor.

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