Rambling Thoughts from a Self-Confessed Atomic Cheerleader
I confess – I like atomic fission power. It is far superior to the competition, so much so that they gang up on it to try to give it a bad reputation. Part of fission’s PR problem is analogous to the way that sports fans and commentators treat people like Alex Rodriguez, Tiger Woods, Barry Bonds, Michael Jordan, and Shaquille O’Neil. All of them are/were athletes who, for a time, dominated their respective sports leagues and put fear into the hearts of all comers who had to try to beat them.
In all cases, each earned a legion of cheering fans but were also subjected to massive quantities of jeering from the opposing fans. They were the subject of delighted negativity from mere mortals and talking heads when they exposed any weakness at all, even if it was unrelated to their job as star athletes. Some of the jeering could be attributed to straight jealousy; these men got paid fantastic salaries and endorsement fees that put them into the stratosphere in comparison to the wages earned by most of their fans and even many of their fellow professionals. Some of the jeering could also be attributed to efforts to take them down a peg or two to make them less effective competitors.
No matter what I hear or read about nuclear fission, I go back to fundamental, first hand knowledge. On the submarines that I had a hand in operating, the source of the heat that made everything work was a relatively tiny mass of material weighing in at less than 0.003% of the displacement of the ship. In comparison, a ship with far less mission capability powered by oil would need to have fuel tanks taking up at least 20 and perhaps 40% of the ship’s displacement.
That ship would be a rather weak competitor because its oil-fired engines would only be able to operate at speed if it was on the surface with access to oxygen from the air and a free dumping ground for the waste products AND it would need to refill those tanks at least 12 and probably more times each year. In comparison, the ships on which I lived for months at a time operated for 15 years without new fuel and they were faster deep underwater than they were on the surface. They did not need any oxygen to make their fuel supply get hot and they did not need to throw away massive quantities of waste material as the fuel got consumed.
Of course, I know all about the cost differentials between mass produced diesel engines and low rate production nuclear steam plants and I recognize that the highly refined fuel used in submarines is a bit different from the somewhat less refined fuel in commercial power plants. However, I also know from both study and direct personal experience as a manufacturer that there are well known processes that allow the gradual reduction of the production cost and improvement in the quality for all goods that are produced in a series fashion and I know that these techniques have rarely, if ever, been applied in the nuclear world.
The fundamental, physical, undeniable advantages that are locked up in the nuclei of uranium, thorium, and other actinides are known to a relatively small number of engineers and scientists. In general, people in those professions have less developed communications skills and have not done a very good job of sharing the wonder that they must feel as they do their daily jobs. Some of them may not even realize just how magical the materials are that they work with on a daily basis because they entered the field after layer upon layer of extraneous caution and back-up systems had been added to disguise the massive quantities of power that come from tiny quantities of material.
I keep three simulated fuel pellets on my keyboard try to help remind me just how incredible the materials are. Those three little pellets, if actually made of uranium dioxide, would contain as much energy as three tons of coal – if they were used in a rather primitive fashion in a once through light water reactor fuel cycle. If fully fissioned, which is possible, they would produce as much heat energy as burning 60 tons of high quality coal.
There are a few engineers and technologists who “get it” and work hard at sharing their wonder with the rest of the world. For a time, Hyman Rickover was one of those people, before he got so worried about the sniping that he was receiving from others that he began isolating and protecting his program’s knowledge and advances. Ted Rockwell, a man who helped Rickover in the early years, left the Naval Reactors program in 1964 and is still writing and sharing his knowledge today at Learning About Energy. There are some creatives who have also learned enough about fission to get excited and begin writing about its great potential for good. I put Gwyneth Cravens, Bill Tucker, Tom Blees, Mark Lynas, and a recent convert, George Monbiot into this category.
There are also some less well known people who are working hard to communicate what they know about nuclear fission in accessible ways here in the blogosphere. I try to keep my blogroll up to date with links to the blogs that devote a good portion of their space to atomic topics.
I subscribe to several email lists and participate in discussions with people who are focused on particular ways to use fission. Not surprisingly, we all look at fission and its place in the world from a different perspective and often argue amongst ourselves about the BEST way to use the amazing qualities of the process. Some of the people on the lists are still quite fearful of the technology and ascribe to the philosophy made most famous by Alvin Weinberg. He often referred to nuclear energy as a “Faustian bargain” and believed that the only way to keep it from sending us all to hell was to isolate it from society under the control of a privileged priesthood of specialists. I disagree with that characterization and oppose the whole concept of limiting the technology to a chosen few.
Some of the people with whom I correspond believe that we need to avoid promoting nuclear energy and that we should question and poke at those “newcomers” like Bill Gates and John (Grizz) Deal of Hyperion. They advise caution and believe that the First Nuclear Age came to halt partially out of hype and over enthusiasm. They are certain that the “new” ideas like smaller, factory producible fission power systems are doomed to fail and that they will inherently cost just as much to license as more complex, site constructed central station power plants.
They get concerned about the “revolutionary” ideas like using liquid metal coolants in fast spectrum reactors – forgetting that the very first reactor to produce electricity to power those four lightbulbs at the National Reactor Testing station was the Experimental Breeder Reactor. They worry that the NRC has “never before” licensed a gas-cooled reactor, forgetting about Peach Bottom and Ft. St. Vrain, which, were, admittedly, licensed before the NRC evolved out of the Atomic Energy Commissi
on. They think that all of this talk about thorium is “nonsense” that has been “tried before” without much success.
They believe that sharing a lot of information about the incredible variety of possibilities for system design will confuse the public and distract our focus. They seem to feel that the entire nuclear community should be working towards completing a limited number of very large facilities on time and on budget to “prove” that such an accomplishment is possible. One of the more troubling, but frequently discussed points is that they fear that any incident at any fission technology installation will inevitably halt all development at all nuclear projects – at least for a time.
My answer is that fission is so darned exciting that it is WAY too early in the development process to limit the scope of the developments or to limit the population of people who can get educated and trained in the math, science and engineering needed to put the physical attributes of actinides to beneficial use. The human population on the Earth consumes enough energy to provide a market for the output of thousands, if not millions of devices that can turn fission heat into motive power and useful processes. There are an infinite number of combinations of coolants, working fluids and process cycles that can work and plenty of ways to make each one of them adequately safe and sustainable.
The development and deployment process may, unfortunately, be a bit messier and unrestrained than some would want, but I like to keep reminding people that it is not as if the competition is even close to perfect when it comes to danger and environmental destruction. The only real competition to atomic fission is fossil fuel combustion. Both are concentrated enough to cause widespread harm if the processes get out of control and both produce waste material that is potentially harmful to living creatures if not well controlled. I just happen to believe – strongly – that it is easier to keep fission materials under control and to isolate their potentially hazardous waste materials.
Bottom line – I am a cheerleader for fission, but I have played in the game enough to know why I cheer and to recognize superior performance when I see it. I plan to continue to share reliable information with all of you, but if I think that ideas are good and useful, I will not try to knock them down just because they are a bit on the unusual side. On the other hand, I will ask hard questions, just to make sure that I am not being “rolled” because of my stated favoritism to fission. I will not try to elevate any fission technology by knocking down another one, but I have little fear of pointing out the challenges that our combustion competitors will have in trying to keep up with the characteristics with which nature endowed actinide fission.
“Rod is referring to standardised components and factory-style mass production techniques. These techniques are at odds with the customised plants of the first nuclear age. His statement is therefore correct.”
Ah yes, because we all know that every fuel assembly, every control rod, and every fuel pellet is a unique product of hand craftsmanship. No two are alike. 😉
Give me a break!
Even nuclear plants come in fairly standard configurations. In the US, the PWR’s are either two-loop B&W plants, two-loop CE plants, or two-, three-, or four-loop Westinghouse plants. These five configurations describe 70 reactors in the US. That’s more reactors than any other country has.
American nuclear plants are no more unique than the various models of Apple computers that have been sold over the years. Last time I checked, Apple is doing OK.
Not every car has to be a Trabi.
To claim that “well known processes … for all goods that are produced in a series fashion … have rarely, if ever, been applied in the nuclear world” is pure foolishness, but Rod did admit that he was “rambling,” so I guess I should give him a pass.
Even nuclear plants come in fairly standard configurations. In the US, the PWR’s are either two-loop B&W plants, two-loop CE plants, or two-, three-, or four-loop Westinghouse plants. These five configurations describe 70 reactors in the US. That’s more reactors than any other country has.
Really? I was under the impression that one of the main factors in the expense of building nuclear plants during the eighties were the idiosyncratic designs of different plants, often forced as a result of NRC mandated design changes.
Actually, the inhomogeneity in American nuclear plants the we observe today resulted from three factors:
1. Competition between the various reactor vendors. Each had its own design peculiarities to differentiate it from its competitors and give it a market advantage.
2. Innovation by the reactor designers. Ideas were brainstormed or borrowed and tried. Some innovations survived and were used in the next plant, some did not.
3. Customizations requested by the customer. In many cases, the utility purchasing the plant requested various customizations to the “standard design” for a particular plant. The nuclear reactor market was highly competitive 40 years ago, so it was nearly impossible for the vendor to say no to such requests. Often one company supplied the reactor, another supplied the generators, and a third company did the architectural engineering. All of this lead to subtle differences in plants of the same design by the same vendor.
Today, factor 1 is still an issue. We currently have five different vendors selling five different designs for sites that have been docketed for consideration by the NRC.
I predict that factor 3 will still be an issue; although it will most likely be less of an issue than in the past. The new licensing rules will discourage such customizations, but it is still difficult to say no to a customer.
Only factor 2 is likely to be less of an issue in the near future. Nevertheless, considering the various untested, innovative designs for SMR’s that are being promoted today, I would not be surprised if the nuclear industry reenters the “innovation” stage. It could be that small, mass-produced reactors could be as wildly varying in design as computer hardware was in the early days of personal computers. Only time will tell.
There was additional expense that was imposed on building many plants in the eighties because of design changes that were mandated after the fact by the NRC in the wake of the Three Mile Island accident.
Let’s hope the this does not happen again. Considering that a couple of NRC commissioners at the time are now solidly in the anti-nuclear camp, the regrettably poor regulation that occurred at time is hardly surprising in hind-sight.
Brian –
American nuclear plants are no more unique than the various models of Apple computers that have been sold over the years. Last time I checked, Apple is doing OK.
The last time I checked, Apple computers sold in quantities of millions of units EACH QUARTER. Even the least popular model sells in quantities of tens of thousands of units. How is that comparable to the 104 total nuclear power plant units currently operating, with several variations among the units as you described.
My experience in series manufacturing included a product assortment of hundreds of individual plastic devices ranging from large deck hatches that might be ordered in volumes of a couple of dozen every few months to throw-away sticks that looked a bit like plastic tongue depressors. I built the cost estimating models for each of those products and can go into quite a bit of detail about the ways that you eliminate or minimize the various overhead components of manufacturing unit you approach the point where the cost of the object is within striking distance of the cost of the raw material ingredients.
I freely admit that the experience of spending three years managing a small American factory with relatively unskilled American labor making plastic products in markets that directly compete with Chinese manufacturers is not directly applicable to the nuclear power industry. There are some lessons that do transfer in understanding how cost and quality control can work or not work depending on the size of components, required production machinery and order quantities involved.
How is that comparable, you ask? Well, in some ways, it doesn’t seem comparable at all. You point out the large difference in the number of units sold; however, I’d say that’s largely irrelevant.
The most important difference is that the vast majority of those Apple computers are now in the junkyard, whereas most of the nuclear plants that have been built in the US are still running today.
Durability counts for something. Manufacturing junk that has built-in obsolescence is one thing. Such an industry has certain advantages for the vendor: there are far fewer issues to worry about. Manufacturing something that is expected to last 40, 60, or even more years is not only a different ball park, it’s a completely different league.
Nevertheless, I’m arguing that the similarities outweigh the differences. In both cases, the vendor finalizes its design, tools up for manufacturing, and produces a product. In another couple of years, the vendor improves its product and offers the next model in the series. In both cases (Apple Computer and the US nuclear industry), this was an evolutionary process. The vendors discovered what worked, what didn’t, and made adjustments to the design to make the most of the best.
Some of the plants that are operating in the US, particularly the older ones, have rather unusual features, as reactor vendors tried innovative ideas that didn’t work as well enough to be incorporated into the next design.
Similarly, Apple experimented throughout the nineties with the design of its Macintosh computer. Ten years ago, I had a friend who made a living as a computer technician who specialized in Apple computers. His job could be frustrating at times, because of the wide variety of hardware that were used in the various models, but he was paid pretty well for his expertise as he had little competition in the computer repair market due to the difficulty dealing with the Apple hardware.
In the long run, high volume has its disadvantages if the manufacturer is willing to stand by his product. (If it’s disposable junk, who cares?) Witness the very expensive trouble that Toyota is having now with recalls. When something goes wrong and needs to be corrected, it is much, much easier for an owners group to deal with a handful of customers rather than thousands or millions.
Toyota’s “gas petal” problem makes Davis Besse’s reactor head problem look like a walk in the park.
You are correct about Toyota’s gas pedal problem. This was caused by Toyota adding complex, computer-controlled, drive-by-wire features to their vehicles without some sort of “sanity-checking”. The lesson? Complexity brings problems with it. Keep it relatively simple, sweetheart.
There are many fine, commercial and industrial grade products that are mass-produced rather than manufactured as one-offs. I could imagine that any mass-produced SMR would have the same quality assurance expectations and level of maintainability that a standard nuclear power plant would, with the possible – and likely – exception of on-site refueling. E.g. after being shut down, all ex-reactor components are meant to be maintained, ripped apart, and reassembled by the trades on site. The piping is of similar quality, the welding is of similar quality, etc. But it would be simple, rather than complex. Rather than having 400 control rods, it would have 4.
Somehow, commercial airliners, locomotives, gas-turbines, cargo ships, industrial diesel engines, and boilers are mass-produced and can last for a very, very long time given proper maintenance. I can imagine that reactors can be manufactured in a similar manner with similar quality in similar numbers, provided that they’re made by a manufacturer willing to stand behind their equipment. I could also imagine that if the use of a breed/burn combination of moderately enriched uranium along with a very high loading of thorium is used, that the core can last for decades.
The Model T was only an analogy. I don’t think there will ever be an option to put a SMR in anyone’s backyard. But I can imagine that many, even most utilities will have them, some in very large numbers, and they will be common, rather than rare. Of course, large plants will also be built, too, as they provide economy of scale that an SMR probably can’t match.
I apologize for not mentioning the application of mass production techniques within the nuclear fuel cycle – the fuel pellets, zircalloy tubes, and even assemblies are produced systematically at a high enough rate of production to have benefitted significantly from both quality and cost reduction improvements. That progress can be seen in the steady reduction of cost per unit heat from nuclear fuel over the past several decades.
That improvement has been enabled by increasing the burn-up from about 10,000 MW-days/tonne of heavy metal in the early days of nuclear energy to approximately 45-50,000 MW-days/tonne of heavy metal in today’s plants. The cost of fabricating the fuel pellets and the zircalloy tubes has also fallen a bit, though, like any manufacturing process, the cost per unit of raw material is out of the control of the fabricators.
There is still a bit of room for improvement – the maximum quantity of heat that can be produced per unit of heavy metal added to a fission reactor could approach 1,000,000 MW-days, so we are about 5% of the way to the theoretical maximum.
For many of the other components of nuclear reactors, there are certainly factory fabrication techniques applied, but the rate of production for coolant pumps, pressurizers, steam generators, and even many of the valves using in the systems is low enough so that each one is essentially a special order that requires far more overhead than would be required if the production were more steady.
@Kit: the point is that further optimization is always possible, and with a small reactor, you can carry optimization a lot further than with a large reactor.
If you build 10 new nuclear plants of 1500 MWe, you can optimize their design to a reasonable degree. You will be able to get costs down significantly if they are all duplicates, built one after another. Build 100, and you get their costs down even more. But with any design integrated at its site, along with the requirement of non-prefabricated building construction at the site, there is a point of diminishing returns on optimization.
If you build 1 million, or 10 million new nuclear power modules of 1.5 MWe, that are pretty much “pour, plop, plug, and play” (the integration is done centrally, at the manufacturing facility, rather than on-site), then optimization becomes essential and will achieve its greatest rewards. All you need is a very good, well-engineered design to start with, one that works well, and is foolproof, and then you optimize for series production. The cost per unit will go down in a practically asymptotic fashion as you build more and more.
The first Model T was the most expensive one, by orders of magnitude. The rest, well, they’re what made Henry Ford rich.
Now do you see what Rod means?
Further, I would say, the first industrialist who gets a manufacturing license for a small, modular, series-producible, install-anywhere nuclear power plant could perhaps become the richest man alive.
(Plus, it isn’t exactly like the Chinese can just copy a SMR – some stuff is too safety-critical for the PRC to build. You need a company with a brand name, built to standards, willing to stand behind their product.)
Keep up the great work Rod. I’m just loading up my iPod with old Atomic Show podcasts to listen to while I’m on the road.
I like to compare the safety of nuclear power to that of aviation. Aviation is “inherently hazardous”, especially as demonstrated by the record of the industry between WWI and WWII. This “inherently hazardous” means of travel has become the safest means of travel on a per-mile basis.
Nuclear has already accomplished the task of taking something “inherently hazardous” and made it orders of magnitude less hazardous than what is comparable — the burning of fossil fuels. Even aviation is not an order of magnitude safer than driving a car.
Aviation isn’t “inherently hazardous”, it is however, not “inherently safe,” very much like the sea, flight is intolerant of error. In both cases risk can be reduced to any arbitrary level by good practice. Fire arms on the other hand, are inherently hazardous since it is function of these instruments to be so, while they can be handled such that they pose little danger to the operator, their purpose is, at a minimum, to project the threat of harm to those on the business end.
The distinction is important. A NPP can be designed, and run such that hazard can be minimized to approach zero, but nothing in the way of safety mechanisms, or procedure, will ever stop a firearm from damaging a target it is willfully discharged against.
I guess that makes us both cheerleaders, Rod. I hear about a new technology and it’s potnetial and I get excited, not worry about why someone else says it “can’t” happen. Any engineer worth his/her salt would do the same.
A telephone poll of 1014 American adults conducted between 4 and 7 March by the Gallup polling organisation found that 62% of respondents favour the use of nuclear energy as one of the ways of generating electricity in the USA. This was the first time that support of nuclear power in the USA surpassed 60% since Gallup began conducting such surveys in 1994. In addition, 28% of people said they
The assembly line analogy is more appropriate to solar cells Rod. Over 2 billion solar cells were produced in 2009. The funny thing about solar cells is that they aren’t actually produced with in-line assembly techniques yet – it’s still a batch processing affair. Two billion cells per year and crystalline silicon solar cell production is still a batch processing affair! This is strange to me. It tells me deep habits are hard to kick.
It’s also funny that solar panel production will reach 10 GW in 2010 and yet have the major participants to agree on a cooperative standardization plan. The basic reason for this is that no one knows which technology will win so no one wants to bet the farm on a standardization path. Nuclear is in a tough spot in this regard. You said it yourself, there are lots of different types of reactors. The multitude of potential designs is one of the things that fascinates fans of nuclear power. But the blessing of diversity is a curse when it comes to standardization. I’m not saying it can’t be done – just makes deciding on a winner much more difficult.
Frayseed:
Series production techniques cannot solve all technology challenges. Even though they were produced at a high rate in automated factories, vacuum tubes still lost when transistors were introduced.
No matter how fast you produce solar cells and how efficient you make them, you are still faced with the incontrovertible fact that the sun sets every single day and that the days get shorter in high latitudes just when energy is most important for human survival. You are also faced with the fact that if you cover an automobile with 100% efficient solar cells, at noon on a clear day you can capture enough power to run a 10 horsepower lawnmower.
I am a big fan of solar powered calculators, emergency roadside telephones, pathway decorative lighting and not much else. All the rest of the applications are a lot of hard work to try to avoid using a far superior technology like radioisotope thermal generators or nuclear power plants.
You forgot to mention betavoltaics, which use solar cells along with a shielded beta emitter to produce power from them 100% of the time.
Now that’s a “solar cell” application that works 100% of the time. Perfect for a laptop battery replacement, or something like that. Only needs to be changed once every 20 years, maybe.
It’s fun to play the what can be solar powered game. People tend to think small: remote controls, smoke detectors, cell phones, cigarette lighters (patent pending), those picture frames with screens on them. It’s also fun to think big also: If you could build a big beta reactor that could power a sub you’d be all over it.
But what about a PV parking space? A typical parking space is a little over 300 square feet. That’s enough for 3 to 4 kW which would conservatively produce 4000 kWh/year in 90% of the US. At 4 miles/kWh that’s enough to power an EV commuter car. Am I going to go out and buy a $30,000 EV and then get my work to install a $20,000 PV parking spot? No to both questions. But if my progressive employer already had a PV covered parking lot and I could buy the EV for $20,000 and I was a little drunk I might think about it. Technically, it looks doable.
I heard the Europeans (read Germans) want to move to all back-back contact solar cell designs. This means you won’t see those lines on the front of PV cells anymore. It also means the cells will be a few percentage points more efficient – perhaps reaching up to 20% absolute. The all back-contact designs come with problems though – in particular they currently cost about 30% more than traditional cells of similar quality. But those accented engineers over there think the all back designs are more amenable to in-line processing. They think they can do away with batch processing and that the higher throughput of the manufacturing process coupled with the higher efficiency of the cells will be able to lower costs. It’s a bold thought. The BAU case for crystalline PV has module costs coming down to 85 cents/Watt in the next 5 years – that’s the BAU case Rod. In the same time frame the BAU case for thin film manufacturers is to take module costs down to 50 to 60 cents/Watt.
I think electricity is fungible Rod. If the price trends continue, PV will become cheaper than retail electricity rates for hundreds of millions of people during the next decade. What is the consumer going to do? Buy from the grid or buy from the roof? Does this affect nuclear power? Not as far as the day to day operation of the grid goes – not the current grid at least. I’m pretty sure it will affect some R&D budgets and some political alliances though.
I do understand that solar PV is getting cheaper. I do understand that battery technology has been developing. (It still does not store anywhere near enough electricity at an inexpensive enough price.) The problem with solar is that it doesn’t work when we want it to – either at night or when it’s cloudy. This is also the problem with wind power. It isn’t reliable – it doesn’t deliver what we need it to deliver WHEN we need it to deliver.
It isn’t the AMOUNT of electricity that matters; the amount can always be increased by building more plants. It’s the QUALITY OF SERVICE that is non-negotiable. Power has to be there 24x7x365.
Anyone can buy or build a generator or nail a solar panel to their roof. That isn’t what your local utility is in business for, however: they are in the electricity business, yes, of course; but the business that they’re in isn’t so much the electricity business as it is RELIABILITY business, in the SERVICE business. They’re there to deliver electricity, yes. But why they’re really there is to deliver reliability, to deliver service. Anyone can generate electricity. Only a public utility, however, can generate it – and deliver it – reliably.
Electricity is fungible. Service is not. Reliability is not. And service – and reliability – is where the enduring value of the utility industry lies. They don’t just light your lights – they keep them burning; they don’t just power your motors – they keep them running. All the time, come what may, day in and day out, month in and month out, year in and year out…
The average person on the street does not care where electricity comes from; all they care about is that it is there when they need it. They care about their life, their liberty, and their pursuit of happiness; they pay others to care about such things as electricity. So the utility industry does care about electricity for them – and so the utility industry will care about electricity for them – as the generation and distribution of as much electricity as the customer needs when they need it is their job, and if anything can be said about the utility industry, it is that it gets the job done. No matter what. Period.
Dave – I agree that the quality of the service is an important aspect of the utility power business, but electricity is not just a service – it is a real physical product even though it cannot be seen.
It has to be delivered with very exacting standards of voltage, frequency, and phase – otherwise it will destroy the devices that it powers. It cannot be created out of thin air; if you want more than just the gleanings from nature that you can pick up with large collectors like solar panels and wind turbines, you need to move and consume quality materials with predictable qualities.
I consider electricity to be the ultimate product; it is hard to think of a single person in the world who would not willingly be a customer for high quality electricity that comes with the right quality of service and with the right physical qualities of voltage, current, phase and frequency. (Yes, folks I understand DC – the correct value for frequency can be 0 for many devices.)
Anyway – I resist agreement with anyone – like Amory Lovins – who insists on describing electricity as a service because that implies that anyone or any organization can be a supplier, even without investing in the physical equipment and materials required.
Electricity is a product and it is arguably the MOST IMPORTANT product in an industrial, developed economy.
If you want equal plants you must have modular design.
The various B&W plants may be the same but they are but equal. I have worked at TMI-I, II, and Rancho Seco. These three plants, for all practical purposes are identical – as far as the NSS side (Components supplied by B&W). BUT, even the NSS is not identical. The power ratings are (were) different even though there is no logical reason for the difference. TMI-I was “Turbine limited” and produced about 20% less power than it could have. It needed a bigger turbine to get the full capabilities and I was under the impression it was a management decision to not spend the extra money at that time for a larger turbine. TMI-II and Rancho Seco were equal in power BUT as TMI-II started later it had severe restrictions on operating parameters due to a famous TMI-II “expert” (you can find his name mentioned in the TMI-II accident investigation.) that insisted upon including all instrument uncertainty AGAIN in establishing all reactor setpoints. (And in my opinion this is what really caused the TMI-II accident. Not the initiator, but the way the crew handled the plant. How would you like to drive a car at 75 on an interstate and then have the road narrowed by 20% knowing that if you touched either lane marker you would be fined?) Even though B&W had analyzed and proven the plant operating parameters they were adjusted again in a conservative direction equal to the total instrument uncertainty. For example the low pressure trip setpoint was 200 pounds higher at TMI-II than at TMI-I and Rancho Seco, putting it 200 pounds closer to normal operating pressure. It would have cost millions and 6-12 months to “prove” that the original setpoints (the same values TMI-I and Rancho Seco have, were acceptable, go figure. Also, since each of the three plants were about a year apart in initial criticality, each of the later two had successively more NRC (AEC for TMI-I and Rancho Seco) “Ratchets” and all had more requirements than Davis Besse. The later two had more trips and other worthless modifications. None of which made any significant difference in safety, but the NRC knew that when you are that close to the cash you will do whatever they say.
Then all three had different architect engineers! Google the plants, they have different shaped buildings, and completely different secondary (steam) side equipment, even different manufacture turbines!
It would be like having three cars with the engine built by RR, and the body built by, Ford, Chrysler, and GM. Going from TMI-I to TMI-II would be like switching from right hand drive to a left hand drive car. How would you like to do that under extreme conditions? That is why you need modular plants.
Don’t even get me started on the “identical design” plants like Bryan, Braidwood, and Marble Hill. They are (were) no more similar than two cars purchased from the same manufacture by two different people. The list of differences in these plants would overload Rod’s server.