Agreed. Ironically, small reactors were all the rage in the 1950s [1]. As the Atomic Energy Commission struggled to find ways to make nuclear power economical,

Agreed. Ironically, small reactors were all the rage in the 1950s [1]. As the Atomic Energy Commission struggled to find ways to make nuclear power economical, there was a conference of reactor advisory committee in October, 1957. They decided that the only way to make the most well-known tech (water-cooled reactors) economical was to scale them up, and how. [1] https://whatisnuclear.com/img/aec-plan-1.png https://whatisnuclear.com/img/aec-plan-1.png Meanwhile, throughout the 1970s the combination of a large number of license applications plus an increasingly concerned public (now fully terrified of radiation from the nuclear weapons atmospheric testing debate) caused regulatory scrutiny to ratchet. Quality assurance, equipment qualification, inspections all became more rigorous. The Browns Ferry fire in 1975 made cable spreading rooms require 3-hour fire barriers and major redundancy. Rooms were added. More expensive materials were needed. Economic struggles continued. Then Three Mile Island happened in 1979. In 1980, the viability of nuclear electricity was in question. Amazingly, the capacity factor of the fleet then increased steadily from 60% all the way up to 90%, making them profitable in the 90s and 00s to the point that a nuclear renaissance was set to occur in 2006-7, helped along by renewed concerns about carbon emissions. At the time, the US nuclear fleet produced about 65% of the nation's low-carbon energy. But then the fracking boom happened. Low natural gas prices brought electricity revenue down in deregulated electricity markets, and the drop in revenue put many nuclear plants in the red. Utilities started replacing nuclear reactors with high-carbon fracked gas plants. Environmentalists didn't care much because solar costs fell 10x and wind was doing great too. Buzz about 100% renewable swept the nation as 10 GW of gas fire up every night in California. Now, the nuclear industry looks back at small reactors, hoping the capital costs can be kept reasonable. It is indeed likely, that small water-cooled reactors using enriched fuel will be very expensive to operate, as they were in the 1950s. Many advanced reactor companies talk about using high-assay low-enriched uranium (20% enriched rather than 5%), which is economic bonkers. But enrichment and uranium are dirt cheap at the moment due to overcapacity from the Japanese and German nuclear shutdowns. This won't last though, and the HALEU reactors will very likely be too expensive to operate if they do actually get built. The ML-1 military microreactor of 1961-65 was 10x more costly than fossil [2]. [2] https://en.wikipedia.org/wiki/ML-1 https://en.wikipedia.org/wiki/ML-1 The most cost-effective thing the nuclear industry can do right now is invest in telling its story. Explain why it's an interesting power source. Explain the value in tiny footprint 24/7 low-carbon power. Most american don't even know that nuclear is low carbon. On the technical side, we need venues to try out some of the crazier reactors that may lead to real cost reductions in today's regulator environment. Put simply, this means we must build reactors that have only a tiny number of valves, cables, motors, etc. that are needed to safely shut down and cool the reactor. Low-pressure coolant reactors may be able to put this together, even though historically they've always been significantly more expensive due to the complexities of dealing with exotic coolants (liquid metals, molten salts, etc.) In 1957, Walter Zinn (director of Argonne National Lab) suggested that liquid metal cooled (low pressure) natural uranium fueled (like a CANDU) reactors were most likely to succeed economically. They'd have low capital cost, very few safety-related systems, and would require very little fuel cycle costs. Today, I think there's a good chance that this kind of concept is still true. Could be molten salt or liquid metal at this point (molten salt reactors weren't really proven until a few years after Zinn's suggestion).