[LINK] Nuclear power stations.

[Kim Holburn]

On 2011/Mar/19, at 12:46 PM, Chris Maltby wrote:

>>> On Fri, Mar 18, 2011 at 10:14 PM, Kim Holburn <kim at holburn.net> wrote:
>>>> No diesel generator just in case!  How did they even start the system up?
> 
>> On 19/03/2011, at 11:31 AM, Fernando Cassia wrote:
>>> I remember reading that generators were available, but were flooded by
>>> the tsunami.
> 
> On Sat, Mar 19, 2011 at 12:03:40PM +1100, Ivan Trundle wrote:
>> This has been mentioned in a number of reports: on-site diesel
>> generation serving the units were mostly crippled by the tsunami: the
>> waves were higher than that modelled, and the facility's protective
>> barriers were breached.
> 
> The backup to the diesels was grid power from elsewhere in the network,
> but the earthquake/tsunami destroyed the grid too (oops). The problem
> for the improvised backup coolant pumping system is apparently an
> inability to generate sufficient pressure to overcome the internal
> pressure of the reactor vessel (and to reach the inlet points high up
> in the structure).
> 
> Diesel backups don't always work under the sorts of loads that a real
> emergency generates, and then there is the issue of keeping sufficient
> fuel supply to run them until the need is gone which may be a week or
> more.

You only need to keep the system up until you can shut the reactors down.

> This kind of risk management engineering is very complex and expensive
> and there are plenty of incentives to take shortcuts. Then there are
> more incentives to cover up the inadequacies when things go pear shaped.
> 
> I doubt if we will ever completely understand the sequence of events
> that led to this being a very serious incident...

I don't believe that but if it were true, we shouldn't be using nuclear fission at all.

-- 
Kim Holburn
IT Network & Security Consultant
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