one aspect of the safety question re nuCLear energy

[drm]

I often see claims that the Chernobyl accident shouldn't count when measuring the safety of nuclear energy because the design was so deficient. But if there was a major upsurge in reactor construction, with thousands being built, isn't it likely and almost assured that some of them would use deficient designs and/or construction practices? It seems that when any technology becomes more commonplace that carelessness is sure to follow. One example of this is that the astonishingly safe modern record for commercial air travel is not achieved in every country. And I expect that the greatest need for new energy generation might take place in some of the countries that can't get the plane safety thing right.

Dean

PS - I capitalized the CL in nuclear because it grates on my ears so much when people say nucular.

[Ed Leaver]

Well... the nuclear insurance industry doesn't count Chernobyl when evaluating liability risk for western plants for that very reason, so why should anyone else?

Its not a rhetorical question though, as other people do count Chernobyl for the reasons you go on to list. Here's the way I look at it.
A #1. Without a very rapid massive roll-out of safe nuclear power this planet's climate is toast. Unreliable renewables and their co-requisite fossil backups are simply too complex and expensive by themselves for the magnitude of the task at hand. Keep both very firmly in mind.
B.      So. How to address your concerns: How do we both keep it safe, and make it massive?
          1. Triage the patients; list the worst emissions offenders: 
              1. China      23.5%
              2. U.S         18.3%
              3. E.U.        14%
              4. India          5.8
              5. Russia       5.7
              6. Japan        4.0
              7. Germany   2.6
              8. Canada     1.8
              9. Iran           1.7
            10. U.K.          1.7
         These Top Ten contribute 79% of global emissions. Then note France (75% of electricity from nuclear) hauls in at number 18 on the list at 1.26%. Ukraine (50% nuclear electricity) is number 20 at 1.08%. I don't know if the E.U. figures double-count France and Germany, but that's not my point.
       2. Visit Country Profiles to see which of these already has commercial nuclear power program. Wait.. they all do.
       3. So do many of the alleged "third worlders" which appear to be of concern. Mexico. Turkey. Brazil. Argentina. Armenia, Romania, Pakistan. Pakistan even has atomic weapons. Poland and Jordan both have planned power reactors. 
       4. Realise the concern is a cultural one. "We" are "more advanced" and have a "much better" safety culture than any to which "they" could possibly aspire.
       5. Oh wait. What about Japan? Or Russia? Or... US? The three nuclear accidents have all happened on the self-styled top-dogs' watch. Each can be at least partly attributed to regulatory failure:
           a. The faulty pressure-relief valve indicator light problem was reported to NRC months before TMI by a sister plant who readily recognized the problem. NRC failed to spread the word, and it took critical hours for the TMI operators to figure it out.
           b. The "positive scram effect" was similarly reported at an RMBK-1000 in Lithuania in 1985. The Soviet regulator and plant designer failed to spread the word. "Possibility too remote to matter." Heh.
           c. The susceptibility of Fukushima Daiichi to 1000-year tsunami was recognized at least as early as 2006,and Tepco increased its seawall spec accordingly. It still wouldn't have been enough, but Japan's NISA failed to check if any corrective action had actually been                taken. It hadn't. Its reasonably certain France's CEA would have shut down such a facility until proper remedial action was taken.

Each accident involved far more than this, of course, and do please read up at the World Nuclear Association's library. But for me the most important take-home point is that "safety culture" is a very human endeavor, undertaken and constructed by humans acting in international concert. The lessons of TMI were hard-learned, though hardly as hard as they might have been. The Soviet RMBK-1000 power reactors ar Chernobyl were designed, constructed, regulated, and operated in cold-war isolation. One likes to hope they would have been different if there had been better collaboration with the west. Fukushima is harder. Those early Mk-I containments were known to be deficient, is why GE so rapidly advanced to MK-II and Mk-III designs. But the reactors themselves appear to have been robust enough, and there is always room for improvement. Where does one draw the line? Its not like you can just jack up a completed reactor and slide a new containment underneath.

On the other hand, the inadequate seawall, seawater-pump sealing, and stand-by generator siting were all items readily amenable to correction.  

The Fukushima Daiichi reactors were designed in the early 1960's and came online in the early 1970's. TMI Unit 2 was nearly brand-new at the time of the 1979 partial meltdown.  Conditions were nothing as extreme as at Fukushima: station power was never jeopardized and the only containment failure was a leaky waste-gas compressor. Even there secondary filtration prevented escape of everything save short-lived chemically and biologically inert Krypton and Xenon, which never posed a health hazard. 

The health risk at Fukushima is similarly overestimated. There have been no radiation-related deaths or injuries, and none are anticipated.

But to answer your questions: No it is not likely and certainly not assured that new reactor designs will be deficient. One needs only consider the recycling of expertise between Westinghouse in the U.S. and Areva in the design selection and improvements for the French build-out that started thirty years ago. Desgnsflowed back and forth between Westinghouse and Areva (or its progenators), and subsequently back and forth between France and China for early Chinese designs, and finally the on-going collaboration between the three countries on the Gen-III AP1000-type reactors being built in China and the U.S. The key is collaboration and communication, and full involvement of IAEA and the national regulatory and oversight organizations. Think of it as a model of how to do this thing right.

Its not the only one. There's the French-Russian-Chinese collaboration (others are involved as well) on sodium fast reactors, with two scheduled for construction in China and two in Russia (Google BN-800 and BN-1200). But its Gen-III+ LWRs that will do the early lifting against climate change. U.K. Has signed agreement with EDF/Areva for two to four advanced EPR reactors, and is soliciting proposals from Russia's Rosatom and U.S. Westinghouse for their versions. Its an international design and construction community.

Construction of course is a bit different, as that is country and site specific. But standardization of international design leads to best-practices and least-error construction everywhere. See  China's nuclear project offers lessons for Vogtle expansion. It is important that IAEA be involved in an observation and advisory role, to make certain that corners are not cut on quality. 

But the most important issue is that 80% o the worlds greenhouse emissions are from eleven countries that already have a well-established culture of safety and quality, and are in fact leaders in nuclear design and construction (U.S., China, Russia, India, France, Canada, Japan, U.K.)  These countries have a long history of successful cooperation and collaboration, and two hard lessons earned when we failed. One way or another, anthropogenic global warming is a global problem requiring international cooperation for global solutions. Commercial nuclear power is but one of them, and probably not the most difficult.

The most difficult will be getting the world to agree to forego coal if the front-end capital cost of nuclear is not lowered sufficiently to beat it.  


 

[drm]

Thanks for your substantive reply. It does give perspective to my concern.



I suppose a different way to pose my question is this: If there were, say, 5000 active nuclear power reactors in operation worldwide, what would be the median number of years between accidents on a scale of Fukushima. And for whatever that number is, can human response to major disasters avoid what Germany and Japan are doing in response - shutting down all their reactors. It's one thing to point to Areva and GE in the current scenario. I find it hard to imagine that with a major boom that new cut-rate mfrs would not show up claiming to be just as safe.



Most humans don't react to risk in a rational way - at least not for large scale risks that are not a part of our daily routine. I understand that coal kills a LOT more people, but we really don't see much response to that much larger but distributed impact. I understand the challenges to large-scale use of wind and solar. Nuclear has it's own challenges. I'm not really optimistic that our society can surmount those challenges enough to prevent us from getting to at least 500 ppm CO2, but here's hoping.

[Grant]

Ed Leaver: "France (75% of electricity from nuclear) hauls in at number 18 on the list at 1.26%." To put this in a little bit of perspective France has less than one percent of the world population but nonetheless does much better than most of its industrial peers as far as per capita carbon footprint and pollution. I'm particularly interested in France because of their leading edge roll in nuclear power, so in a sense you can say they are the future in that regard. Politically apparently Fukushima has caused some pull back in nuclear power at least with the present French government. Understandably increased safety is a concern. In my view if nuclear is going to have a future it's going to be in the close looped world and I'd like to see what is happening in that regard in France. Among other things that would seem to imply a more localized process all around which would appear to speak to safety. I understand they are doing some reprocessing but I'm not clear how fully that gets them to a nuclear closed loop world. Burial of spent fuel seems wasteful plus a guarantee of NIMBY politics.

Anyway I'm basically here to get educated and ask questions. I found this site an interesting discussion of France's nuclear program, past present and future.

en.wikipedia.org/wiki/Nuclear_power_in_France

On the negative side as the earth heats up that will increase the plant water cooling problems.

On a positive side more electrical cars will be around to soak up the now sometimes unused nuclear capacity.

[Grant]

A little addendum.

France is the world's largest net exporter of electricity due to its very low cost of generation, and gains over EUR 3 billion per year from this.

About 17% of France's electricity is from recycled nuclear fuel.

[Ed Leaver]

Dec 28, 2013 3:09:54 GMT 9.5 drm said:

Thanks for your substantive reply. It does give perspective to my concern.



I suppose a different way to pose my question is this: If there were, say, 5000 active nuclear power reactors in operation worldwide, what would be the median number of years between accidents on a scale of Fukushima. And for whatever that number is, can human response to major disasters avoid what Germany and Japan are doing in response - shutting down all their reactors. It's one thing to point to Areva and GE in the current scenario. I find it hard to imagine that with a major boom that new cut-rate mfrs would not show up claiming to be just as safe.



Most humans don't react to risk in a rational way - at least not for large scale risks that are not a part of our daily routine. I understand that coal kills a LOT more people, but we really don't see much response to that much larger but distributed impact. I understand the challenges to large-scale use of wind and solar. Nuclear has it's own challenges. I'm not really optimistic that our society can surmount those challenges enough to prevent us from getting to at least 500 ppm CO2, but here's hoping.

... and that's a very good way of posing the question. A "MTBF on scale of Fukushima" would be a figure people might relate to, and I don't have a good answer at this time. We should look around the next few weeks to see who else does. One extreme is cited by Prof Joe Lassiter in his update to his recent essay:

As part of a Bayesian analysis, Jack Devanney of Martingale estimates that on average we will have one such nuclear core casualty every 3,000 reactor years. For the current fleet, that's about one every 10 years. If the world were to go all-out nuclear for electricity, we would eventually be talking about one core damage event every calendar year, unless we can substantially reduce the failure rate with new designs.

Emphasis added. The problems here are several. Firstly, you did not ask about just core damage frequency, but rather core damage frequency coupled with containment failure on scale of Fukushima. Secondly, our last US power reactor was completed thirty years ago, and even those plants were substantially improved over those deployed in the 70's. TMI prompted further (intense) rethinking by the industry and NRC. Current Gen III and III+ designs did not happen overnight -- they've been under development since that time. Nobody is going backward, even the Gen II plant (finally) being completed at TVA's Watts Bar easily surpasses NRC requirements, and will be the last of its kind.

Thirdly, another estimate is readily obtained from WNA's library article Safety of Nuclear Power Reactors, which gives a MTBF for core damage of GEN III+ plants of 10 million years. 10 million per reactor / 5000 reactors gives something like 2,000 years. That's just a ballpark estimate for core damage and would include TMI type accidents where there was essentially no containment failure and no hazardous radiation release. But Fukushima? That's a toughy -- I haven't read Devanney's Martingale analysis so won't be hypercritical -- but I would caution against extrapolating too far from a sample size of one. It's still a good question, though.

Your final point about "cut-rate manufacturers claiming to be just as safe" is also worth addressing. I think it can be, with the requirement that IAEA be involved in the scrutiny of all new designs, to make sure the design itself is safe. Then there is construction, where the same applies.  Safety culture must be a continued and ongoing international endeavor. But do note that while GEN III+ LWRs will bear the early brunt of the climate issue, they are not the be-all and end-all of reactor design. Gen IV liquid-metal and molten-salt designs are intended to be "walk-away safe" and the early prototypes have been (successfully) tested as such. But they're a later chapter of the story, and you've nailed the question: "Given what we've got -- renewables and current nuclear reactor designs -- how do we limit ghg emissions sufficient to avoid catastrophic climate change?"

And if that were all we had, I'd share your pessimism. Current reactor designs are more front-end capital costly than coal. On the back end renewables are more costly even than nuclear when asked to go the 85+% distance required. But that isn't all we've got. In addition we've got human ingenuity. So I look for something like this:
1. Formulate National and global Energy Plans outlining courses of deployment of current designs and development of new. (Renewables included) They might include something like
2. Us rich and relatively rich guys (U.S., E.U., Russia and much of FSU, India, Pakistan, China, Japan, Brazil, Argentina, etc) can go ahead with Gen III+ deployment and push development of Gen IV plants with goal of modular designs that are cheaper than coal. They must be safer as well. This can be done. 
3. As shown earlier, its us rich&relatively rich (R&RR) that emit the preponderance of global ghg. We've already got a working international safety culture and IAEA that must be strengthened and expanded. Public awareness might be critical. The important thing is we have the regulatory infrastructure. What we need is the political leadership (Hillary? Chris?) to promote these institutions on the national and international scene.
4. If planned for, sometime this century (the sooner the better but don't hold your breath) molten salt designs will come online. These are really quite elegant: like liquid metal reactors they operate at ambient pressure, but in addition their cores are already molten which allows fission decay products to be removed on a continuous basis. There is no residual decay heat to deal with after shutdown. While IAEA scrutiny is still requisite for safe design, the plants themselves would be largely impervious to shoddy construction. Build 'em too cheap and they will break. You'll then have an expensive repair bill and it will serve you right. But there won't be any radiation release, so you can learn something and go do better next time.

Please try to keep in mind we don't have to solve all of the worlds problems. Just the climate catastrophe looming this century. After that its up to the great-grand kids. Leave some of the fun for them. If they decide to peacefully reduce world population by 90% and let their grand kids live off hydro and renewables fine, that's their decision. I'd just like to leave them the quantities of clean energy they'll need to make it.