Skip to main content

Of Valves and Venting

monticello The New York Times starts the story of the valves this way:

After the venting failed at the Fukushima plant, the hydrogen gas fueled explosions that spewed radioactive materials into the atmosphere, reaching levels about 10 percent of estimated emissions at Chernobyl, according to Japan’s nuclear regulatory agency.

It’s a very interesting story and at least feels like the start of the narrative of what happened at Fukushima Daiichi. But the discussion of valves and venting careens off in very odd ways.

American officials had said early on that reactors in the United States would be safe from such disasters because they were equipped with new, stronger venting systems. But Tokyo Electric Power Company, which runs the plant, now says that Fukushima Daiichi had installed the same vents years ago.

Gulp! Did anyone ask the Nuclear Regulatory Commission or perhaps a utility here in the states about this? Nope.

Tokyo Electric has said the valves did not work at Fukushima Daiichi after the power failed.

That would suggest that operators of similar plants in the United States and Japan could protect reactors by moving generators to higher floors if the equipment is currently in places that could be affected by tsunamis or flooding from rivers.

But a redesign of the venting system itself might also be necessary.

Matt Wald, who wrote this story, seems to have had second thoughts, particularly about the similarity of Japanese and American plants when it comes to the implementation of valves.

Yet since 1989, when the Nuclear Regulatory Commission told American plant operators that it liked the venting idea, the thinking has changed further on the operation of boiling water reactors. For one thing, most American reactors have been allowed to bolster their steam output so they can make more electricity. To get permission to do this, a reactor owner must arrive at a calculation that the emergency core cooling system could still work in case of excess heat.

Some plants now anticipate high pressure, and, in fact, require it for safe operation.

So there was divergence, at the least. Here’s a little more, specific to valves:

If the vent is operated with an electrically driven valve, as in the current design, operators can control how much steam they let out and how much pressure they keep in. The alternative is probably a rupture disk, a thin piece of steel that breaks at a pre-designed level, just below the pressure that is likely to rupture the containment.

Wald goes on to express some doubts, but the point is that he learned more about valves and venting and shared that with his readers. What started out fairly damning became considerably less so with some further research.

---

Some of the concern with valves comes from an engineer named Anthony Sarrack:

Anthony Sarrack, working with another Monticello engineer, wrote a white paper in 2005 raising concerns about a venting system designed to rid boiling water reactor containment vessels of excessive pressure during accidents by releasing it outside.

But Sarrack says he left the industry in 2006 after spending a frustrating 19 months trying to persuade the regulators and industry officials to consider his proposed solution.

"As an industry, they don't want to make changes," he said.

Monticello is in Minnesota, which is why reporter David Shaffer tells this story in the Minneapolis Star-Tribune.

The Union of Concerned Scientists has caused some mischief with Sarrack’s findings, but as usual, there’s more to the story. There’s this:

The Monticello plant has a backup system powered by compressed nitrogen that officials said would power the vents if the plant lost all power. The venting system has never needed to be used, the utility said.

So one of the big concerns – that the vents would lose power if a plant does - is not really so.

Then, this:

Doug True, president of Erin Engineering and Research, a Walnut Creek, Calif., nuclear consulting firm, said Sarrack's proposal "never got any traction" in the industry because many people disagreed with its merits.

"There was lot of consideration on how to use these vents, and on balance people generally felt the way they were installed was the preferred way," he said.

So Sarrack may have been frustrated that his ideas didn’t get much pickup – fair enough - but suggesting that they weren’t given consideration isn’t really true. (Sarrack also says his bosses at Monticello never tried to silence him and that he later left of his own accord – so conspiricists do not have much of a stick to use here.)

The subject is a little esoteric, I know, but because the New York Times made a pitch of it, it picked up more interest than it probably warranted. But the interesting thing is that reporters – including the original reporter - kept digging into it and finding it, at best, rather problematic. On the other hand:

An NRC spokeswoman said the vents will be reviewed as the agency studies the lessons from the Fukushima disaster.

Well, why not? Where’s the harm? It’s even as it should be.

Monticello. The valves are – okay.

Comments

Will Davis said…
Thanks for following up on the New York Times. They need to be brought to task for this kind of reporting.
Ross said…
The plant in the photo is Palisades in Michigan, not Monticello.
Darek Shapiro said…
Read that NY Times article, and was more miffed then now at the NRC. Your investigative reporting took follow through and patience. Yet patience is something I am short of, when it comes to the GE nuke plants operators on the California coast, and Indian Point plant in my backyard. Going to the NRC hearing on 6/2/11

Popular posts from this blog

Sneak Peek

There's an invisible force powering and propelling our way of life.
It's all around us. You can't feel it. Smell it. Or taste it.
But it's there all the same. And if you look close enough, you can see all the amazing and wondrous things it does.
It not only powers our cities and towns.
And all the high-tech things we love.
It gives us the power to invent.
To explore.
To discover.
To create advanced technologies.
This invisible force creates jobs out of thin air.
It adds billions to our economy.
It's on even when we're not.
And stays on no matter what Mother Nature throws at it.
This invisible force takes us to the outer reaches of outer space.
And to the very depths of our oceans.
It brings us together. And it makes us better.
And most importantly, it has the power to do all this in our lifetime while barely leaving a trace.
Some people might say it's kind of unbelievable.
They wonder, what is this new power that does all these extraordinary things?

A Design Team Pictures the Future of Nuclear Energy

For more than 100 years, the shape and location of human settlements has been defined in large part by energy and water. Cities grew up near natural resources like hydropower, and near water for agricultural, industrial and household use.

So what would the world look like with a new generation of small nuclear reactors that could provide abundant, clean energy for electricity, water pumping and desalination and industrial processes?

Hard to say with precision, but Third Way, the non-partisan think tank, asked the design team at the Washington, D.C. office of Gensler & Associates, an architecture and interior design firm that specializes in sustainable projects like a complex that houses the NFL’s Dallas Cowboys. The talented designers saw a blooming desert and a cozy arctic village, an old urban mill re-purposed as an energy producer, a data center that integrates solar panels on its sprawling flat roofs, a naval base and a humming transit hub.

In the converted mill, high temperat…

Seeing the Light on Nuclear Energy

If you think that there is plenty of electricity, that the air is clean enough and that nuclear power is a just one among many options for meeting human needs, then you are probably over-focused on the United States or Western Europe. Even then, you’d be wrong.

That’s the idea at the heart of a new book, “Seeing the Light: The Case for Nuclear Power in the 21st Century,” by Scott L. Montgomery, a geoscientist and energy expert, and Thomas Graham Jr., a retired ambassador and arms control expert.


Billions of people live in energy poverty, they write, and even those who don’t, those who live in places where there is always an electric outlet or a light switch handy, we need to unmake the last 200 years of energy history, and move to non-carbon sources. Energy is integral to our lives but the authors cite a World Health Organization estimate that more than 6.5 million people die each year from air pollution.  In addition, they say, the global climate is heading for ruinous instability. E…