Page 47 - Energize November 2022

TECHNICAL

Ignoring accurate financial
calculations
Neither previous plans to build new large
nuclear reactors, nor the PBMR plans, were
too expensive. But the anti-nuclear activists
were very effective in persuading the
public otherwise. The nuclear development
teams made careful and accurate financial
calculations showing that the projects were
totally affordable. In addition, the price of
the resulting electricity would have been
similar to that of the coal-fired electricity
at the time. These calculations were all
checked by foreign financial consultants.
History has now shown them to have been
correct.
But there was a massive wave of anti-
nuclear propaganda generated by activists Figure 2: Diagram showing the fuel energy density of uranium, about a million times that of
in which the real budgets and expenditure petrol and coal. This is why nuclear power plants using uranium can generate huge amounts of
patterns were highly inflated and distorted, energy using very small volumes of fuel.
and then provided to the media. In addition,
the propaganda implied that all the money The HTMR-100
would be paid to a single foreign supplier Simpler, cheaper and faster-to-construct
and would be committed in one single Sometime after the PBMR project was stopped, a group of nuclear scientists and
payment. In fact, the budget had been engineers got together and formed the company Steenkampskraal Thorium (Pty)
calculated to be spent over a period of 15 Ltd, known as STL Nuclear. They started designing a simpler, cheaper and faster-to-
years, certainly not as a once-off payment. construct version of the PBMR called the HTMR-100. This design produces 100 MW
In addition, multiple companies, both of thermal energy (100 MWthermal), which generates 35 MW of electrical energy (35
domestic and foreign, would have been MWelectrical).
contracted to carry out various aspects of Two critical changes were made. One was to reduce the helium gas outlet
the total task, rather than just ‘one supplier temperature from 940°C to 750°C. This was done to reduce some fabrication
takes all’. Furthermore, some of anti-nuclear constraints and so reduce costs. The second major change was to take the helium gas
comments in the media stated that ‘this from the reactor via a conventional heat exchanger and drive the turbines with steam,
payment is equal to the entire budget of the rather than to pass the helium gas directly into the turbines. This meant that all the
country’. plant ‘from the heat exchanger downwards’ could be purchased off-the-shelf and
therefore did not need to be designed. This decision of course implied a simpler design
The fleet approach verified process and a much simpler construction of the entire power station.
The original 9600 MW proposed for the Currently the design of the HTMR-100 is such that construction can start on the
large nuclear build project represented first-of-a-kind (FOAK) plant. Current estimates are that the FOAK can be built in five
three complete power stations of years.
approximately 3200 MW each, built over
a period of 10 to 15 years, at the rate that Process-heat: a highly profitable potential option
the country could afford. This was called The HTMR-100 was designed to not only produce electricity, but also to produce heat
the ‘fleet approach’ and was designed to be for industrial processes, without the need to first make electricity. Calculations show
the cheapest way to build the three nuclear this to be a highly profitable potential option.
plants. History has shown that those plans At the time of the PBMR, Sasol showed great interest in an SMR to produce
and projections were all correct. We would process heat, since a huge amount of coal needs to be burned to produce the heat
not have load shedding today had that to chemically convert the rest of the coal into fuel. Enormous cost-savings could be
project continued. attained if all transported coal could be converted to fuel and chemicals, without
It is interesting to note that a four- burning any of it for process-heat. Other applications for the HTMR-100 could include
reactor nuclear power station, called water desalination, among others.
Barakah, has been built in the UAE, and
that its final cost matches closely the South Variable fuel options
African calculations carried out by nuclear The HTMR-100 was designed to run on uranium, or thorium, or a mixture of the two.
professionals 20 years ago. This was done in consideration of the nature of the potential world market which

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