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| Three Mile Island Nuclear Plant courtesy Google Maps |
process engineer working in a chemical plant on the Houston Ship Channel. March 28 was a Tuesday, just another ordinary day, until the word began coming over the radio that a nuclear plant in Pennsylvania was having troubles. Radiation leak was the phrase.
As was normal then, and still is today, the nuclear industry was in full protect-thine-own-butt mode, with as little information made public as possible. And then, only the bare minimum. Those guys knew then, and know today, full well that their industry hangs on a slender thread. One screwup, one meltdown, one massive radiation release into the sky or water, and they are done.
As it turned out, TMI, as it was known, suffered "only" a partial melt-down. The reactor operators screwed up, and screwed up royally. They actually turned off a water pump that sent water into the core, and that act let the core overheat and melt down. Eventually, they started that pump again and sent water into the core, but by then the damage was done. The nuclear core had melted almost entirely through the reactor vessel's wall. In their (operators') defense, the plant designers and those who approve the design did not give the operators a way to watch the water level in the reactor core. They had to infer the water level by watching other measurements. That was a design error that was changed in other US nuclear plants.
All of the trouble started when a pump failed to operate. As I wrote a few years ago in the Truth About Nuclear Power series, part 21:
"TMI (meltdown) was caused by a routine mechanical failure of a pump. Nobody can claim that a pump failure is a rare event. The problem at TMI was made much, much worse by a valve that stuck open. It is inexcusable that nuclear plant designers, operators, and oversight agencies failed to recognize that valves sometimes stick. The fact that valves sometimes stick in the open position, sometimes closed, and sometimes in-between is well-known to those in the process industries. This particular valve was a relief valve. Relief valves are even more prone to sticking open, a fact that is common knowledge. Yet, as the facts below demonstrate, TMI operators made blunder after blunder because they believed the relief valve closed by itself – they believed it had not stuck open.
"Nuclear proponents frequently argue that the reason nuclear plants cost so much is due to needless design changes by the NRC during plant construction, and costly retrofits to those plants already in operation. The argument is invalid. We would indeed be a stupid society to allow plants to operate with known safety deficiencies such as existed at TMI before the accident. In fact, if not for the existence of all three required containment systems, deadly nuclear radiation would have spewed all over the northeastern corridor of the United States. Those three levels of containment are the fuel tube, the reactor vessel, and the containment building. Ultimately, the fuel tubes failed and melted, the reactor vessel barely contained the melted fuel, and the containment building contained most, but not all, of the gaseous radioactive particles.
"With the passage of time, more than 3 decades now, TMI has faded into the background. Yet, the lessons from that incident are serious, and point to what we can expect going forward." see link to the rest of the TMI meltdown analysis on SLB.
Fast forward 40 years to today, and we see the nuclear industry still points to the TMI incident as the turning point where the public mood for nuclear turned sour, and costs to build new nuclear plants began to zoom. Today, a plant cannot be built for less than $10 billion for a 1,000 MWe output. More typical is $12 billion. That is approximately 10 to 12 times the price of a natural gas power plant with the same output. We saw just recently that two new reactors were abandoned, unfinished, as completely out of the question due to construction costs rising and rising. Two more reactors, these at Vogtle in Georgia, are staggering along, many years late and many $billions over their budget. Only time will tell if the Vogtle reactors ever get finished, and what the final cost will be.
In retrospect, nuclear plants seemed appropriate in the 1960s and then the 1970s after the oil price increases during the OPEC oil embargo. We burned fuel oil then to make electricity, as strange as that sounds today. Nuclear plants had almost zero fuel cost, we were told back then. So, scrapping expensive oil as fuel, and building nuclear plants with very cheap fuel might have made sense. After all, solar and wind power systems were possible, they actually worked, but their costs were outrageously high. So, we built nuclear plants, approximately 120 of them.
Today, though, all that has changed. Wind turbines have declined in cost and improved in output, and the same is true for solar PV systems. Also, natural gas power plants no longer are limited to the modest efficiency of a steam plant, with the Rankine cycle. Improvements over the years now make the combined-cycle gas turbine plant much more efficient, at 60 percent. Low natural gas prices also exist today due to superb innovations in natural gas production that uses precision directional drilling and hydraulic fracturing.
Because of these things, we no longer have a need for nuclear power plants. They served their purpose, they had their day. It is time to retire them and stop building them.
We note that it is seldom, and perhaps never, that a meltdown occurs in a shutdown nuclear power plant. We don't need another Three Mile Island meltdown. We need clean, safe, low-cost wind energy with efficient natural gas plants to accommodate the variations in output.
Roger E. Sowell, Esq.
Houston, Texas
copyright (c) 2019 by Roger Sowell - all rights reserved
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