Posted on 04/04/2011 1:37:52 PM PDT by drmatt
There have now been three serious accidents at commercial nuclear reactors: Three Mile Island in 1979, Chernobyl in 1986, and Fukushima Daiichi in 2011. The Three Mile Island accident was largely the result of operator error, with very little release of radioactivity and no deaths as a result of the accident. Since this accident, the U.S. has significantly improved the operational procedures and safety design of its approximately 100 commercial reactors. The accident at Chernobyl was largely the result of operator error and an unsafe Soviet-era design without a containment structure. Despite the fact the reactor completely blew apart from a massive steam explosion and follow-on hydrogen explosions, the death toll was approximately 50. The Fukushima Daiichi reactor complex survived the magnitude 9.0 quake, but the tsunami that followed caused a common-mode failure of all emergency and back-up power systems. As a result, one or more of the reactors has experienced a core meltdown. But the vast majority of the radioactivity will remain within the reactor vessels, containment structures, and spent fuel pools. These reactors are all shutdown and the residual heat rates from the fuel rods are diminishing with time as the result of natural radioactive decay. The nuclear plant workers, Japan Defense Force, firefighters, and other emergency workers have been making a tremendous and courageous effort to restore cooling and stabilize the situation. There have been no deaths as a direct result of this accident, compared to the many thousands of deaths caused by the earthquake and tsunami.
For advanced societies that require large amounts of energy to remain advanced, the only viable sources of energy for the foreseeable future are nuclear power and fossil fuels. A sound energy policy would make use of both of these sources of energy to provide diversity and energy security. But clearly we should strive to make improvements in both nuclear technology and safety. Several advanced reactor concepts are being evaluated throughout the world for the next generation of nuclear energy. The U.S. Congress initiated the Next Generation Nuclear Plant (NGNP) project in 2005. Based on a systematic evaluation of several next-generation concepts, the Department of Energy (DOE) selected a Modular High Temperature Gas-cooled Reactor (MHR) as the concept for NGNP. A key design feature of the MHR is intrinsic safety. The MHR can survive a complete loss-of-coolant accident, including failure to insert control rods, without reliance on any emergency systems. As the reactor heats up, natural processes will shut it down. Because the reactor core and nuclear fuel are composed entirely of refractory and ceramic materials with capacity to absorb heat at high temperatures without structural degradation, there is no damage to the reactor, i.e., the reactor cannot melt down under any circumstances. No public evacuation is required, even next to the plant’s entrance gate. With its high temperature capability and efficient heat utilization, the MHR can generate electricity with high efficiency and displace fossil fuels for a number of petrochemical and industrial applications, including production of hydrogen for future clean fuel utilization. San Diego-based General Atomics (GA) is a pioneer of this technology. With partners from the U.S., Japan, and South Korea, GA is now completing the conceptual design of the NGNP demonstration plant for the DOE.
Japan has also been developing MHR technology on its own. Sitting above and just south of the small fishing village of Oarai, and about 100 miles south of the Fukushima reactor complex, is the Japan Atomic Energy Agency Oarai Research Establishment, which includes the High Temperature engineering Test Reactor (HTTR). The HTTR was commissioned in 1998 and is an operational, engineering-scale prototype of the MHR. The HTTR has been used to demonstrate the intrinsic safety characteristics of the MHR and has also demonstrated sustained operation with a 950C (1740F) coolant outlet temperature. By comparison, conventional water-cooled reactors operate with a 300C coolant outlet temperature, and are obviously not intrinsically safe.
The efforts in Japan should now be focused on helping the victims of the earthquake and tsunami and on stabilizing the damaged Fukushima reactors. But perhaps these events that occurred in Japan can also lay the foundation for developing, demonstrating, and commercializing a next generation of nuclear power with intrinsic safety. International collaboration among the U.S., Japan, and other nations on the MHR would provide a relatively quick path for achieving this goal.
More information about the HTTR can be obtained from:
http://www.jaea.go.jp/english/news/p110112/index.shtml
http://www.jaea.go.jp/04/o-arai/nhc/index.html
More information about the NGNP project can be obtained from:
http://www.nextgenerationnuclearplant.com/
Remember that dog they rescued in the middle of the ocean after spending 3 weeks floating on a roof..? They brought him into shore:
http://www.youtube.com/watch?v=wLMYp6RL08A
(English subtitled)
I took a power and energy class in collage and one part was a debate on Nuke power. The pro nuke guy said that the China Syndrome was a figment of Jane Fonda’s bank account. The lives lost in the accident are fewer than would have been lost providing the same amount of energy with coal. Underground mining used to be the most dangerous occupation in this country.
I spent most of 2007 working at the HTTR site in Oarai. The parts of Oarai near the coastline were flooded by a 4-m tsunami following the quake. I was saddened to see a video of some of the same streets I used to walk and drive on:
http://www.youtube.com/watch?v=qM6usF56Wpk
It is ironic that Oarai means “big wash.” Fortunately, all of my Japanese friends that I worked with are OK.
oh wow, bro! I used 2 go 2 that beach all the time...!!!
:(
Small world..! Wow that jiiChan was rockin some major HouBen...wow...
And quite frankly, Chernobyl shouldn't count, because that facility was purposefully built in an unsafe manner.
I’m still for it. I think giving money to Muslims for arms and weaponry is an even worse idea. Learn the lesson; survey very carefully where you will put such a plant.
I could understand almost NOTHING that guy said....this is soooo weird. Is that even Japanese...?! I’m almost sure that narrator was not Japanese...
Chernobyl must be counted, men are men, societies are societies. Not all are responsible, and their come periods of very irresponsible cultural behaviors even in otherwise responsible cultures.
Chernobl was a poor design. Most contries had stopped using graphite moderated reactors back in the ‘50s as they are very unstable at low power levels.
TMI was an example of systems which worked and with modern computer systems probably never would have failed.
Japan failed due to lack of a reliable back-up power solution. Reactors require about 10MW just to run pumps and computers. The backup generators were destroyed by the wave and thus after the SCRAM, no power existed to run cooling pumps. Simply moving the generators 30ft above ground instead of 10ft below would have saved the plant.
How about:
Don’t built a nuclear reactor: (a) on a massive fault and (b) the tsunami area at the same time.
Chernobyl was a RBMK reactor with graphite moderator and water cooling. This combination can result in unstable operating conditions, and did with Chernobyl. The MHR has a graphite moderator but uses inert helium as the coolant. It does not require any back up power, even after a complete loss of coolant accident.
This was Tepco’s operating procedure:
“In an attempt to solidify its cover-up, TEPCO prepared two versions of in-house inspection reports—an internal one with actual data and an official one with falsified data—for regular inspections at both of the nuclear power plants during those years, according to Hitachi’s internal documents.”
Once it was known this was the kind of company operating a Nuke plant ...and there were many more coverups and issues...so many it boggles my mind...
Someone should have gotten in there and done something about the safety.
Lots of non-Japanese in Oarai working in the fishing industry.
One of the problems with current generation light water reactors is the low thermal efficiency - about 33%. This means 67% of the heat generated by the reactor must be dissipated to the environment, which is why many reactors are loacted near the ocean or other large bodies of water. With its higher thermal efficiency, the MHR can be located in much drier areas. The thermal efficiency is ultimately limited by the laws of thermodynamics, but the MHR can operate much closer to this limit, with efficiencies near 50%.
I may be wrong, but I seem to remember that they were testing water systems in an unsafe manner, something to that effect as well.
They were building a similar model in Cuba, but construction, thankfully was halted before it went operational.
I live in the shadow of a nuke plant in Limerick. I am not afraid one bit.
It's a shame, the greenies will propagandize this to death.
We Must stop funding the mortal enemy of the world, Islam. With common sense solutions, I'll put my money on the "can do" Americans.
Is it the same design as Chernobyl? Big difference.
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