DEAR News Of The Area,

I’VE been reading the letters surrounding the nuclear energy debate, and one piece of misinformation often gets quoted.

It was quoted again on 19 July.

In attempting to dismiss claims that Small Modular Reactors (SMRs) are not viable, proponents of nuclear respond with: ‘What do you think powers nuclear ships and submarines then?’

On the surface that sounds like a reasonable argument.

However, all is not as it seems.

A SMR (Small Modular Reactor) is not a snr (small nuclear reactor.)

They may both be small, but that does not make them the same thing.

The small nuclear reactors used by naval ships and submarines use highly enriched uranium to enable them to be so compact.

Nuclear reactors that are used for generation of electricity for everyday use are fueled by uranium enriched with approximately 3.5 percent – 4.5 percent U-235 (which naturally occurs as about 0.72 percent of all uranium isotopes.)

The small nuclear reactors on board ships and submarines require an enrichment of at least 20 percent, and usually well over 50 percent.

This difference in enrichment percentages is highly significant.

As can be imagined, the cost of enriching uranium fuel to 50 percent or more is significantly greater than it is to enrich fuel to just four percent.

And that makes all the difference.

The costs of fuel are not a big factor that military budgets must take account of.

However, the costs of fuel must be taken into account for commercial nuclear reactors.

The objective of those working on SMRs is to make the reactor small and modular, yet also keeping the cost of fuel low.

That has not been done.

So, please correspondents – distinguish between a SMR and a snr.

Regards,
Bruce Meder,
Coffs Harbour.