想定外

[Alan Siegrist]

David J. Littleboy wrote:

> From: "Alan Siegrist" <AlanFS...@Comcast.net>
> >>>>>>>>>>
> The important thing is the spare emergency diesel generators
> themselves and they would do the most good close to where they would be needed.
> Perhaps they could be mounted on trailers and located in protected
> enclosures on high ground away from the threat of flood or tsunami,
> but close enough to be towed quickly to where they are needed.
> <<<<<<<<<<<
>
> No. The important thing is only using designs that can't, in
> principle, produce a mess that can't be easily cleaned up when everything goes wrong.
> The existing designs are all far too complex, far too dependent on
> equipment that is itself too big, complex, and high precision to be
> expected to be there or to be substituted for by fire hoses spraying
> seawater when something goes wrong.
>
> There are several new designs (travelling wave and modular for
> example) that have that property. There's a basic engineering
> principle, usually stated as "Murphy was an optimist", that tells you
> not to make things that you are going to be really unhappy about if everything goes wrong.
>
> It's not impossible to do nuclear in a safe manner. Even in it's
> current state, nuclear is two orders of magnitude safer than coal, and
> that's not including the minor detail that coal is guaranteed to make the planet uninhabitable.
>
> But currently, all existing reactors are Fukushimas waiting to happen,
> and they can't, in principle, be fixed.

Thank you for your well-reasoned comments. Perhaps the incident at
Fukushima has indeed exposed an inherent design flaw in existing
reactor designs.

We have to hope that the lessons of Fukushima are reflected in the
designs of new reactors that will be built from now on.

The problem, then, is with the existing reactors in operation that
share this flaw. Simply shutting them all down immediately may not be
feasible from a practical standpoint, and even a shut-down reactor is
still vulnerable to the same problem as we also saw at Fukushima, but
a plan to systematically replace the existing reactors of flawed
design with newer designs might very well work. This will
unfortunately take decades to implement.

In the meantime, as you correctly point out, we have lots of
Fukushimas waiting to happen.

However, the plan I outlined to provide spare off-site emergency
diesel generators for every power station could indeed prevent similar
loss of coolant accidents (LOCA) in the meantime, before the reactors
can be replaced, at a very modest cost of perhaps several million
dollars for the entire country.

The entire amount of the expenditure for the spare generator plan is
probably being spent every day right now in the cleanup at Fukushima.

Even if one similar accident could be prevented in this manner, it
would be money well spent.

Regards,

Alan Siegrist
Carmel, CA, USA