Vultures Picnic and Diesel Generators

Vultures Picnic is the latest work of investigative reporting by multi-award-winning journalist Greg Palast. I will admit to being ill-disposed to this book as I find Palast’s prose style teeth-grindingly irritating. The book is couched more in the style of a travelogue mixed with a murder mystery. If you like your journalism dry and well-referenced this book is not for you.

I have no idea whether the criminal and political conspiracies laid out in the book are accurate. I’ve seen some of the same claims made by other journalists — usually much better sourced — so I’ve no reason to believe that Palast is making anything up. His nose for politics and money seems good, but he seems to have a blind-spot when it comes to technical issues. He often seems to rely on a single source that tells him what he wants and never mind the evidence.

In one particularly jaw-dropping chapter Palast makes the bold claim that the emergency diesel generators (EDGs) on all nuclear power stations can’t work. To quote from page 343..

In other words, the diesels are junk, are crap, are not capable of getting up to full power in seconds, then run continuously for days. They’re decorations attached to nuclear plants so people will think these radioactive tea kettles are safe.

The nice thing about this claim is that it’s easily testable. Has a nuclear power station ever run on its EDGs after losing off-site power? As it happens, yes.

In August 2011 The North Anna plant in Virginia was hit by an earthquake just off the coast. This event caused both its reactors to go into emergency shutdown. As well as triggering this shutdown the quake also took out the offsite power. All four EDGs at North Anna sprang into life and supplied power to the emergency systems until offsite power was restored; exactly as they were designed to, and exactly as Greg Palast says they can’t.

So why does Palast make this claim? Well he has history with EDGs. He was part of the legal team that charged LILCO with conspiracy charges around the building of Shoreham Nuclear Power Station. The corrupt and incompetent LILCO bought prototype, untested generators from a company called Delaval rather than proven generators that would have cost 5% more. These three underspecified generators promptly failed on testing and LILCO were forced to buy the more expensive generators.

Now, I can see how that experience could sour one on the nuclear industry, but it’s a long way from “these three generators failed” to “all generators must fail”. This is where Palast’s inside man appears. There is a long conversation with an unnamed engineer wherein Palast is informed that starting EDGs to full power in seconds puts lots of mechanical strain on them and they aren’t designed to deal with it. The engineer makes the point that the same diesels when used to pull trains or power ships are generally warmed up slowly. All of which is true, but beside the point. EDGs are required to run for hours not years, so shortening their operational life a bit by hard-starting them is a sensible trade-off.

If you are particularly cynical you might be thinking that they got lucky at North Anna. How do we know other generators would perform as well? Because the NRC requires you to actually test that they work.

For the purposes of SR 3.8.1.2 and SR 3.8.1.7 testing, the DGs are started from standby conditions. Standby conditions for a DG mean the diesel engine coolant and oil are being continuously circulated and temperature is being maintained consistent with manufacturer recommendations.[ In order to reduce stress and wear on diesel engines, the DG manufacturers recommend a modified start in which the starting speed of DGs is limited, warmup is limited to this lower speed, and the DGs are gradually accelerated to synchronous speed prior to loading. This is the intent of Note 2, which is only applicable when such modified start procedures are recommended by the manufacturer.
SR 3.8.1.7 requires that, at a 184 day Frequency, the DG starts from standby conditions and achieves required voltage and frequency within 10 seconds. The 10 second start requirement supports the assumptions of the design basis LOCA analysis in the FSAR, Chapter [15] (Ref. 5). ]The 10 second start requirement is not applicable to SR 3.8.1.2 (see Note 2) when a modified start procedure as described above is used. If a modified start is not used, 10 second start requirement of SR 3.8.1.7 applies.

Since SR 3.8.1.7 requires a 10 second start, it is more restrictive than SR 3.8.1.2, and it may be performed in lieu of SR 3.8.1.2.In addition to the SR requirements, the time for the DG to reach steady state operation, unless the modified DG start method is employed, is periodically monitored and the trend evaluated to identify degradation of governor and voltage regulator performance.

Got that? Every 31 days do a gentle start of the EDG (if the manufacturer recommends it, else do a hard start) and every 184 days hard-start the EDGs to prove they can get to full power in 10 seconds. The only difference between the hard-start test and an emergency is that you are allowed to run the oil and lube pumps beforehand to reduce the wear on the engine.

If you have a problem with that testing regime take it up with the NRC, and don’t believe everything Greg Palast tells you.

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