Yes. Most of the problems with reactors have come from parts that are glossed over at the PowerPoint level. Many exotic reactor designs have been built, and most have had problems. Everything with complexity inside the radioactive area has been troublesome.
The AVR pebble-bed reactor in Germany had a pebble jam, and still can't be decommissioned.
Often the problems involve plumbing. Sodium reactors have leaks and sodium fires. Helium gas-cooled reactors have helium leak problems. Ft. St. Vrain was a really good idea which had both helium leak and corrosion problems. Three Mile Island was a valve problem. Fukishima was a failure of the cooling system after a tsunami.
This is why some of the new designs are viewed skeptically. Molten salt reactors involve a chemical processing plant that works on radioactive materials. Radioactive chemical plants have always been troublesome. They tend to become toxic waste sites. (See Pantex, PUREX, etc.)
Modular reactors with multiple reactors sharing the same cooling pool are at risk if anything leaks and contaminates the pool.
Commercial reactors have to be built for a 40-50 year lifetime to pay off. Anything inside the radioactive zone is essentially unmaintainable for that period. Complexity inside thus just doesn't work.
Which is why we're stuck with water and pressurized water. Simple mechanically and chemically.
The placement of generators at the base of the containment structures was already a mitigation to another risk: that ground movements common to the area might damage or destroy the generators.
A complex environment is one in which multiple risks constrain options and operations. Generators can be placed neither high nor low without assuming risks or requiring additional mitigations.
If a solution space is a search through a complex multidimensional topology, constraints place bounds on that space.
Come on, there's a lot of know-how to building a platform that can resist an earthquake.
An alternative is build a waterproof wall around it. Or enclose it in a waterproof enclosure. (We do know how to build submarines.)
With some thought, you can think of many more arrangements much more resilient than what they had, and would not have been particularly expensive.
Such as bulldoze a mound and put the generators on top of that.
Other problems with Fukushima had similar simple solutions. Instead of venting hydrogen gas into the enclosed building, where it built up and exploded, vent it to the outside. Cost: a vent pipe.
Not an expert in any of the related fields, but Japan is also a heavy seismic activity zone. Piling up loose dirt is just asking for liquefaction.
My armchair spectator opinion is that I want each reactor 'unit' built in an engineered safe solution, far up, supported by a seismic isolation system. Up in the hills, where people would be sent to evacuate after the earthquake due to the tsunami risk? Yeah, put that thing there.
Also the plant engineers need to be personally authorized and held responsible to do whatever it takes to keep things "safe" in the event of a disaster. They're on site, they're seeing the details, let them have the authority to ensure the greatest possible safety.
> Piling up loose dirt is just asking for liquefaction.
Having investigated this myself when I bought property for a house, this is not expensive to deal with. Heck, my neighbor did. You bore a hole with a big auger, fill it with concrete, and set the structure on it. You can even build skyscrapers on fill with such (see San Francisco).
The only reason these problems were not addressed when Fukushima was built is because people didn't think of it in their failure analysis, not because it is expensive, impractical, or impossible.
There is nothing fundamentally wrong with the Fukushima design, just details.
That limits the cooling water supply. Almost all large reactors are near bodies of water. Palo Verde in Arizona is one of the very few exceptions. They operate a sewerage disposal plant to get water.
Often the problems involve plumbing. Sodium reactors have leaks and sodium fires. Helium gas-cooled reactors have helium leak problems. Ft. St. Vrain was a really good idea which had both helium leak and corrosion problems. Three Mile Island was a valve problem. Fukishima was a failure of the cooling system after a tsunami.
This is why some of the new designs are viewed skeptically. Molten salt reactors involve a chemical processing plant that works on radioactive materials. Radioactive chemical plants have always been troublesome. They tend to become toxic waste sites. (See Pantex, PUREX, etc.) Modular reactors with multiple reactors sharing the same cooling pool are at risk if anything leaks and contaminates the pool.
Commercial reactors have to be built for a 40-50 year lifetime to pay off. Anything inside the radioactive zone is essentially unmaintainable for that period. Complexity inside thus just doesn't work. Which is why we're stuck with water and pressurized water. Simple mechanically and chemically.