nuclear-news

A critical analysis of future nuclear reactors designs

By D A. Ryan,  Once upon a time I used to be a fan of nuclear energy. As far as I saw it, nuclear energy was the silver bullet solution to all of our energy problems and more. However, the more I’ve learned about the industry the more critical I’ve become.

Notably the fact that most of the economic figures in support of nuclear power (a couple of typical delusions you’ll find here and here) come straight out of Hogwarts school of magic, wizardry….and economics (more realistic appraisals of nuclear economics can be found here and here).

All in all my conclusion is that the case for future Generation IV nuclear reactors is much narrower than the supporters of nuclear energy would have you believe. While they do offer some advantages over LWR’s, notably in the area of safety, this comes with strings attached, notably higher capital costs. This is largely a result of the fact that many of these would need to be built from much more exotic materials, such as high temperature stainless steel alloys  Nickel alloys or Refractory materials, while the predominant material of choice in current reactors is steel (stainless and forged ferritic) and concrete. This materials requirement is itself an issue related to the high temperatures these alternative reactors would be required to operate at, not to mention the more aggressive and corrosive environment in some of them, notably the MSR proposals. Of course one to question whether these higher construction costs (and in some cases higher decommissioning costs) are justified……..

Small to medium sized modular reactors do offer a good deal more flexibility in terms of how nuclear power could be used and yet a further improvement in safety. However, they also comes with lower economies of scale and thus higher construction costs and worse a slower rate of reactor roll out (at least in the early days). We could claw back on these two issues by mass producing said reactors in large volumes but as I point out (again see the full article), it is far from proven whether that would be economically viable and whether there is in fact a market for large numbers of small reactors…….
by and large mass production means “dumbing down” our design, and that means accepting a reactor that’s much cheaper and easier to build but has a lower thermal efficiency, a higher rate of fuel consumption and ultimately produces larger volumes of nuclear waste compared to our “mega” reactors. With the exception of a small number of narrow cases, it’s difficult to envisage how this would offer an improvement on the current status quo…..

July 25, 2012 - Posted by Christina Macpherson | 2 WORLD, Reference, technology