Sunday, December 23, 2007

Nuclear rambling

I suppose it's fortunate that Glenn Reynolds is from Knoxville, TN, which is also the home of the Tennessee Valley Authority (TVA). Also, Oak Ridge National Laboratory (ORNL) is nearby, thus assuring that Tennesseeans (notably His Greenness Al Gore) have both awareness of and economic interests in nuclear technology. Anyway, GR links to a Metropulse article here, which has inspired the disjointed ramblings that follow.

TVA has an unequaled record in the nuclear power business - no other US organization has undertaken more nuclear power plants, and no other has abandoned more. Browns Ferry near Athens, AL; Sequoyah, near Chattanooga, TN; Watts Bar*, near Maryville, TN; Bellefonte**, near Scottsboro, AL; Hartsville A** and B**, east of Nashville, TN; Yellow Creek**, near Corinth, MS; and Phipps Bend**, near Surgoinsville, TN. The asterisks denote units started but not (yet?) completed.

Around 1982 TVA recruited at my engineering school. At the time they were looking for people to construct Watts Bar and Bellefonte. They cautioned, however, that Watts Bar would be finishing construction in the near term future and thus there was more work at Bellefonte. Fast forward 25 years - Bellefonte ceased construction sometime around 1985, Watts Bar Unit 1 has not been running for long, and the board has recently voted to finish Watts Bar Unit 2.

The article briefly mentions the Browns Ferry event. A bit of background may be in order here.

It so happens that one of the big issues with fire protection anywhere is compartmentalization - you don't want fires to be able to spread. As it happens, there's not much to burn at any nuclear power plant I've ever worked in (4 different sites, 7 units, 3 different utilities, 1 PWR and 3 BWRs, 2 NSSS suppliers), but then I started in the industry after the Browns Ferry event.

Anyway, compartmentalization means preventing heat, flames, gases and combustion products from leaving the area where they started. This means that penetrations from one compartment to another must be sealed such that they can resist pressure differentials. Such penetrations might be for personnel access, ducts, pipes, wiring and other purposes.

A good way to detect air leaks is by releasing something visible and airborne in the vicinity and watching it - if it moves, then the air is moving too. One such "something" is an open flame from a candle. And one of those open flames caused a fire that demonstrated that the seal wasn't adequate... (if that's not ironic enough for you, wait until you hear how a govt notorious for not being able to manage farms managed to foul up Chernobyl - look for "The aim of this test was to determine whether cooling of the core could continue to be ensured in the event of a loss of power").

TVA is easy to pick on - they're big, quasi_govt, and they have a lot of political clout. At one time at least their top executives were not permitted to make any more money than a Congressman does, so it was difficult to recruit and keep good people. Also at one time at least they were governed by a 3 man board, further complicating governance.

And the incomparable Jimmy Carter installed S. David Freeman as one of those governors. We'll see nothing else quite like this until the Pope starts running Planned Parenthood. During his tenure TVA started abandoning the many sites above, and later he moved on to the Sacramento Municipal Utility District (SMUD), which has shut down their Rancho Seco reactor.

I suppose it sounds like I'm ripping on TVA. Well, the truth hurts, but actually I'm rooting for them. The fact is that TVA has had lots of operating and construction experience and for the most part has stayed out of the newspapers outside their territory. Browns Ferry was expensive and embarrassing, but it was about 30 years ago too under a much different regulatory regime.

No, the ones I'd like to rip on are those who use asininities like "Frankenstein construction" (see the Metropulse link above). Often people like this claim to fear global warming too (when they're not denying associations with Nazis, racists and skinheads - diabolical cheap shot,eh?). Here's a hint - any energy/environmental problems we might have will be solved by engineers and those who support them financially, not those who preen and jawbone for a living.

This is a Google satellite map of Bellefonte site. The large round objects casting shadows to the north are the cooling towers. The smaller round-topped objects to the northeast are the reactor buildings. Between the reactors is the auxiliary building, further yet is the turbine building, and beyond that is the switchyard where the power comes in and out. Southeast of the reactors are buildings for construction staff and fab shops, and further yet past the wooded area is the Tennessee River. To the east about halfway up the map is the intake pumping station which draws cooling water from the river for the condenser, HVAC and other cooling loads.

Another thing about Bellefonte. The original nuclear steam supply (NSSS) was a Babcock and Wilcox design. It's sad but true that whatever their other merits, B&W also supplied the NSSS for SMUD and Three Mile Island. Apparently they'll be replaced with Westinghouse equipment. It'll be interesting to see how this will be incorporated into the site. By the time they're through they may be using little of the original plant besides the intake pumping station and the cooling towers.

The article goes on to mention the reduction in suppliers to the industry. I'll note that the concern about the forges, if accurate, only applies if we keep on applying the technologies used in the currently operating generation of plants - other technologies might not need such huge vessels. Long term NWA readers saw this a few years ago noting how it would be difficult to ramp back up to support a growing industry. IMO there's a moral in there for those who would cut the armed services too deeply too.

An aside about Rancho Seco. I don't know much of its history, but I know that at one time in the early 80's they pulled a good one that certainly took a bite out of their low capacity factor. It seems that they connected a backup diesel generator to a live grid before they started it. If you wanted to do something similar at home, you might try running your car at top speed and then slamming it into reverse. Anyway, I wouldn't be me if I didn't grind my favorite axe and note that it was run by a govt organization (Sacramento *Municipal* Utility District).

Enough for now, so this post doesn't suffer a slow death by editing like so many others have lately.