[michael1999]

The US army tried and failed. The US Air Force tried and failed. The marines keep trying. Japan has had several fatal accidents in their civilian program just handling fuel. Even the navy limits them to specialist roles, and their success and safety record might all hinge on the legacy of one gifted man (Rickover).

I support research and trials of the SMRs, but you might want to consider the possibility that it really is hard at the full-system level. The human mind does not readily understand invisible, exponential process like radiation.

[DennisP]

Every power source has accidents. Deaths per TWh for nuclear are comparable to wind and solar. Every form of fossil is much worse. Hydro beats everything for major disasters; Banqaio Dam killed 26,000 people immediately and many more in the aftermath.

[freeflight]

> Deaths per TWh for nuclear are comparable to wind and solar.

A statistic that only works because epidemiological studies into the long term effects of radiation exposure are extremely difficult, complex and time consuming.

Something made even more difficult by the fact that we blasted uranium fallout in the atmosphere that's hanging around to this day, so getting a non-affected control group has become pretty much impossible.

Ain't helping that any research attempting to investigate the problem will very quickly be labeled as highly controversial by pro-nuclear lobbies [0]

[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2696975/

[DennisP]

What makes it even more difficult is natural background radiation. The global average is 2.4 millisieverts/year, with the US averaging 3.1 and Japan averaging 1.5. Medical scans add 0.6 mSv/year. Airline crews get an extra 2 mSv/year.

By comparison, atmospheric nuclear tests added 0.11 mSv at their peak in 1963, declining to 0.005 mSv/year today. Chernobyl added 0.04 mSv in 1986, declining to 0.002 today. The nuclear fuel cycle adds 0.0002 to the global average, and is required to be less than 1 mSv for all members of the public.

The highest natural background radiation is in Ramsar, Iran, with 6.0 mSv/year. Studies are ongoing but the evidence so far shows no negative health effects.

Note that Sieverts are normalized to the health effects on the human body. Any concerns about different types of radioactivity are already accounted for in this measurement.

Chernobyl and Fukushima of course caused larger exposures to nearby inhabitants, and these exposures are accounted for in the statistics I mentioned.

https://en.wikipedia.org/wiki/Background_radiation

https://en.wikipedia.org/wiki/Sievert

[michael1999]

I'm sure the Army, Air Force, or Marines would if they practically could. The promise of power density with no logistics tail is magic. They choose not to because of practical, operational reasons.