Japan taps industry to build safer, more secure nuclear energy future
- Reference: 1664459111
- News link: https://www.theregister.co.uk/2022/09/29/mitsubishi_heavy_safer_nuclear_reactor/
- Source link:
The country put a stop to the construction of new nuclear plants after a tsunami hit the eastern prefecture, home to the Fukushima Daiichi Nuclear Power Plant, resulting in the most severe nuclear accident since Chernobyl in 1986. Now many of Japan's reactors lie idle.
In pursuit of carbon neutrality by 2050 and energy security due to Russia's war in Ukraine, the Japanese government [1]has been considering a return to "next-generation nuclear reactors equipped with new safety mechanisms."
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With this shift, a new partnership led by Mitsubishi Heavy Industries with four power utilities – Kansai Electric, Hokkaido Electric Power, Shikoku Electric Power, and Kyushu Electric Power – to develop an "innovative light-water reactor based on existing units of the same type" to be launched by the mid-2030s, [3]as reported by Nikkei Asia .
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Kansai Electric Power said in a statement: "We have been studying the design of a next-generation, light-water reactor with improved safety and economy, and are working with Mitsubishi Heavy Industries."
The project builds on Mitsubishi Heavy's pressurized light-water reactor that has been used by the four power utilities. It will be capable of producing between 0.6 million and 1.2 million kilowatts of electricity.
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The focus is on improving the control-rod drive mechanism, responsible for adjusting nuclear reaction, to halve output or bring the reactor back online in 17 minutes, about a quarter of the time it takes existing reactors.
Robustness is also crucial, with the design purported to withstand natural disasters, terrorist attacks, and aircraft crashes. "The companies want to reduce the reactor's probability of sustaining damage to less than 1 percent of current models by installing it underground and fortifying the outer walls of the containment vessel," Nikkei said.
Beneath the containment vessel, a "core catcher" will be installed to prevent molten fuel escaping in the event of a meltdown. Emergency power systems can then also used to cool the reactor will be strengthened and located on-site.
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Mitsubishi Heavy is also working on smaller and more efficient nuclear plants capable of producing 0.3 million kilowatts, as well as high-temperature, gas-cooled reactors to produce hydrogen.
Prime Minister Fumio Kishida's "green transformation" council has also been tasked with examining how Japan's existing reactors could be upgraded to safer light-water units. Light-water reactors are cooled and moderated with ordinary water as opposed to those that use heavy water (deuterium oxide, D 2 O).
[8]Japan reverses course on post-Fukushima nuclear ban
[9]Nuclear power is the climate superhero too nervous to wear its cape
[10]Europe's largest nuclear plant on fire after Russian attack
[11]Fukushima studies show wildlife is doing nicely without humans, thank you very much
Elsewhere, as the International Energy Agency does not believe 2050 carbon emission goals are achievable without nuclear power, there have been signs of innovation in small modular reactors (SMRs), notably in Britain, where [12]Rolls-Royce has secured funding to build plants based on the design.
SMRs are much smaller than the current generation of nuclear reactors under construction and produce far less power. But what they lack in economies of scale, they make up for in modular design and off-site construction.
The [13]International Atomic Energy Authority says that "prefabricated units of SMRs can be manufactured and then shipped and installed on-site, making them more affordable to build than large power reactors, which are often custom designed for a particular location, sometimes leading to construction delays. SMRs offer savings in cost and construction time, and they can be deployed incrementally to match increasing energy demand."
However, a study by Stanford University and the University of British Columbia concluded that SMRs may generate [14]up to 35 times more waste to produce the same amount of power as a regular plant. The research and methodology was heavily contested by companies developing the technology.
In any case, a global surge in nuclear power could be on the cards as governments wake up to climate change and over-reliance on rogue states for their energy needs – as demonstrated by the [15]Nord Stream pipeline crisis . ®
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[1] https://www.theregister.com/2022/08/24/japan_reverses_course_on_postfukushima/
[2] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2YzXBHXC3tEk5DVUG2A29SwAAAAI&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[3] https://asia.nikkei.com/Business/Energy/Japan-s-Mitsubishi-Heavy-to-develop-safer-nuclear-reactor
[4] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44YzXBHXC3tEk5DVUG2A29SwAAAAI&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[5] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=3&c=33YzXBHXC3tEk5DVUG2A29SwAAAAI&t=ct%3Dns%26unitnum%3D3%26raptor%3Deagle%26pos%3Dmid%26test%3D0
[6] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44YzXBHXC3tEk5DVUG2A29SwAAAAI&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[7] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=3&c=33YzXBHXC3tEk5DVUG2A29SwAAAAI&t=ct%3Dns%26unitnum%3D3%26raptor%3Deagle%26pos%3Dmid%26test%3D0
[8] https://www.theregister.com/2022/08/24/japan_reverses_course_on_postfukushima/
[9] https://www.theregister.com/2022/08/15/nuclear_power_climate_change/
[10] https://www.theregister.com/2022/03/04/zaporizhzhia_nuclear_power_plant_fire_battle/
[11] https://www.theregister.com/2021/09/24/fukushima_wildlife_diversity/
[12] https://www.theregister.com/2021/11/09/rollsroyce_smr_funding/
[13] https://www.iaea.org/newscenter/news/what-are-small-modular-reactors-smrs
[14] https://www.theregister.com/2022/06/02/nuclear_reactors_waste/
[15] https://www.theguardian.com/environment/2022/sep/28/nord-stream-methane-gas-leaks-may-be-biggest-ever-with-warning-large-climate-risk
[16] https://whitepapers.theregister.com/
Re: Over-reaction much?
Are you talking about earthquakes? Relatively low "high-rises" and the most advanced earthquake proofing construction for modern buildings (post 80's).
The focus is on improving the control-rod drive mechanism, responsible for adjusting nuclear reaction, to halve output or bring the reactor back online in 17 minutes, about a quarter of the time it takes existing reactors.
The problem with rapidly dropping output and then bringing it back up in a hurry is neutron poisoning by Xe 135 . Finer control of of the control rods might help in burning it off a bit faster, but there's one hell of a risk of instability.
Beneath the containment vessel, a "core catcher" will be installed to prevent molten fuel escaping in the event of a meltdown. I believe this is to both catch and quench, the catcher being constructed of lead. Like a dead mans brake.
That idea is not new, it just has been waiting to be implemented. To recap the Fukushima disaster, reactor no 1 was damaged, and a decision needed to be made whether or not to pump seawater into it to cool it down - which as a side effect would write-off the reactor due to the salt water corrosion. Seawater cooling was started, then HQ (the board of TEPCO, about 50km from the site) decided almost immediately to stop it, hoping to later repair the reactor, while the on-site manager, suspecting a melt down, quietly disobeyed orders and started the seawater cooling up again, unknown to HQ.
Months later, it was discovered that reactor number 1 had actually melted down (through the bottom of the reactor), and was also discovered that the on-site manager had continued the cooling - and his decision had been the right one in terms of safety - possibly preventing a far worse Chernobyl type disaster. He got a reprimand from HQ, while HQ eventually got an even bigger reprimand and criminal charges from an investigative panel later on. Meanwhile, the leaked meltdown is looking to cost hundreds of billions of dollars over several decades.
Human error, war, natural disasters - shit happens and a fail safe is needed. Of course it will be more expensive to construct, but a lot cheaper in the long run.
Over-reaction much?
"The companies want to reduce the reactor's probability of sustaining damage to less than 1 percent of current models by installing it underground "
Hopefully they are applying the same rules to office towers in Tokyo