Fusion reactors may never work

journal Science has run an article arguing that a power-producing fusion plant might never be practical. He is not saying they won't produce fusion, since they already do, nor that getting over breakeven is impossible. Just that it will probably never be economic to build a fusion power plant.

"The history of this dream is as discouraging as it is expensive," wrote William Parkins, a physicist who worked on the Manhattan Project during the second world war, who later became the chief scientist at US engineering firm Rockwell International.

Sadly, Parkins passed away while his lengthy paper, which makes its case on engineering grounds, was being edited. But Donald Kennedy, Science's editor considered the paper important enough to run the piece posthumously, in a condensed form, and to stand behind its conclusions personally.

He appears to be mainly critising the large Tokomac style reactors such as JET and Iter, and you can see his point all magnetic confinement devices are limited to neutron producing fuels so do have a problem with their components becoming radioactive. Haft lives tend to be short so often the life cycle of one of these devices is seen as run for twenty years, leave for another twenty for radiation levels to drop to background, then dismantle and rebuild. Which would be expensive, but until we actually do build one nobody will really know quite how expensive.