Forgot your password?
typodupeerror
Japan

Japan Restarts World's Largest Nuclear Plant as Fukushima Memories Loom Large (bbc.com) 49

New submitter BeaverCleaver shares a report: Japan has restarted operations at the world's largest nuclear power plant for the first time since the 2011 Fukushima disaster forced the country to shut all of its reactors. The decision to restart reactor number 6 at Kashiwazaki-Kariwa north-west of Tokyo was taken despite local residents' safety concerns. It was delayed by a day because of an alarm malfunction and is due to begin operating commercially next month.

Japan, which had always heavily relied on energy imports, was an early adopter of nuclear power. But in 2011 all 54 of its reactors had to be shut after a massive earthquake and tsunami triggered a meltdown at Fukushima, causing one of the worst nuclear disasters in history. This is the latest installment in Japan's nuclear power reboot, which still has a long way to go. The seventh reactor at Kashiwazaki-Kariwa is not expected to be brought back on until 2030, and the other five could be decommissioned. That leaves the plant with far less capacity than it once had when all seven reactors were operational: 8.2 gigawatts.

This discussion has been archived. No new comments can be posted.

Japan Restarts World's Largest Nuclear Plant as Fukushima Memories Loom Large

Comments Filter:
  • do u want godzilla (Score:2, Insightful)

    by Anonymous Coward
    because this is how u get godzilla
  • by eepok ( 545733 ) on Wednesday January 21, 2026 @12:19PM (#65939772) Homepage

    I appreciate the contribution and insight of the esteemed Slashdotter "BeaverCleaver", but typically there's an article link that comes along with a summary,

    • by Tablizer ( 95088 )

      To be fair, the /. editors often rearrange an original submission such that perhaps it's merely an editorial snafu.

      • To be fair, the /. editors often rearrange an original submission such that perhaps it's merely an editorial snafu.

        There was some editing (Which probably did improve my submission) but there was definitely a link in my original submission. When you submit to Slashdot there's a big box to paste the link into! I assumed the link would be displayed with the story... or, if not, that the human editor would drop it in there with all their other changes.

        Next time I submit a story I'll make sure to stuff some link(s) into the main text of the submission too.

    • From BBC? (link) (Score:5, Informative)

      by Tablizer ( 95088 ) on Wednesday January 21, 2026 @12:25PM (#65939788) Journal
    • by dfghjk ( 711126 )

      'I appreciate the contribution ... of the esteemed Slashdotter "BeaverCleaver"...'

      The serial killing you mean?

    • I've noticed that on the occasional article. Eventually I found that a link is also in the title. In this case, the "bbc.com" linked directly to the story.

        Japan Restarts World's Largest Nuclear Plant as Fukushima Memories Loom Large (bbc.com) 42

  • Woah (Score:3, Insightful)

    by SumDog ( 466607 ) on Wednesday January 21, 2026 @12:24PM (#65939784) Homepage Journal
    I didn't realize so many of their nuclear reactors had been shut down! That's a massive loss of power. Nuclear reactors are incredibly powerful, and the safety issues are really born out of ignorance. NRC regulations in the US would have prevented a lot of what happened at Fukushima. Most plants have multiple backups, gravity fed cooling and emergency pumps that can operate even if fully submerged in a flood. Even Three Mile Island couldn't happen today, as reactors are tripped (shutdown) immediately even if there's small amounts of variance in a turbine.

    Even Browns Ferry (one of the most dangerous reactors in the US honestly) finally got its 3rd unit fully operational a few years ago after being shutdown for decades (there's a great Smarter Every Day video about that).
    • by Tablizer ( 95088 )

      Japan seems to have repeated bad luck with nuclear technologies. While I don't condone superstitiousness, I can understand their population's hesitancy.

    • Re:Woah (Score:5, Informative)

      by Whateverthisis ( 7004192 ) on Wednesday January 21, 2026 @01:27PM (#65939948)
      A couple of things, and caveat I spent a brief time working in the nuclear industry in a consulting capacity, and I was in a hotel on a business trip having a drink with the VP of Bus Dev of Westinghouse Nuclear watching the news reports of Fukushima as it literally happened right then.

      First, in the Japanese cultural psyche nuclear power is a very prominent thing. Japan has the dubious distinction of being the only country in the world to have been hit with nuclear weapons in anger, and the cultural shock of that paired with the utter destruction of their society after WW2 was very significant. You can see it in the subtext of their culture, for example the entire Godzilla franchise is heavily influenced by the fears of nuclear power and the devastation it can wreak on society. Even in anime, the various Macross franchises, they used the term "reaction engine" or "reaction warheads" as a coded word for "nuclear" because the word nuclear has a very strong cultural reaction to it, and nearly every Macross series you see has some angle of some super weapon that could, and often does, destroy entire worlds. It's deep in the cultural psyche there, so when there is a problem and the word "nuclear" is attached to it, the society there shifts around it.

      After Fukushima, Japan shut down all 54 of their nuclear power plants in response. That of course made them a massive importer of fossil fuels, whcih they don't have natural access to. Fears and cultural issues with the term nuclear eventually were bested by pure economic factors; nuclear is cleaner than fossil fuels, provides more power, and has a less supply chain issues while giving Japan greater control over it's energy grid. Around 15 reactors have started back up under stricter safety guidelines.

      To your point about plants having gravity fed cooling and multiple backups, that's not exactly true. Modern reactors, like the AP1000 [wikipedia.org] use gravity cooling, this is called a Gen III+ reactor. The issue though is that reactors are really expensive to set up, and often times it's more economical to extend the service life of an older reactor than build a new one. So while you are correct about new built reactors, most Gen 1 reactors are retired but many Gen 2 reactors are still active and do not have those features. In the specific case of Fukushima and Japan, Japan has a very unique challenge. You always want to build nuclear reactors near water so you have active sources of cooling. For Japan, that means the coast. The problem though is that Japan is also very seismically active. Fukushima was designed to withstand some severe earthquakes and had pumps that were fully automated that should be able to keep the reactor cool for 1-2 days in an emergency, which is often enough to bring in more permanent solutions. What happened with Fukushima it was hit by a greater than 9.0 earthquake off the coast which created a tsunami (it's notable we use the Japanese word for tsunamis because they're so common there). The massive tsunami came in and wiped out the generators that run the pumps, knocking out all of it's backup cooling stations. The plant, 40 years old, did what it was supposed to do, but was hit with something beyond it's design specs.

      And that's the real issue. An AP1000 could have managed Fukushima due to it's passive cooling, but the vast majority of active reactors are Gen 2. Most Gen 2s are good, but they don't have those passive systems, they still rely on generators and pumps for the cooling. Japan built it's reactors knowing their seismic situation, but the earthquake that hit Fukushima was exceptionally large and beyond what it could do.

  • by AgTiger ( 458268 ) on Wednesday January 21, 2026 @12:28PM (#65939796) Homepage

    For those who need a refresher as to how the failure of the Fukushima reactors, see this video:

    Understanding the accident of Fukushima Daiichi (from 2012)
    https://youtu.be/YBNFvZ6Vr2U [youtu.be]

    Total time: 13:01. The key bit is at 4:49: "The waves went over the sea wall flooding the lower parts of buildings, and disabled the emergency diesel generators."

    Had those generators and fuel tanks been higher up in the structure, things probably would have been fine, but with the reactors in control-rod shutdown and needing to dissipate the residual heat in the reaction chambers, the secondary cooling systems powered by those emergency diesel generators were absolutely crucial.

    • How about multiple backups?

      • They had multiple generators. All were at the same height because they decided not to put them on pylons (obligatory build more...) because the people in the surrounding area said they didn't want to look at them. Or maybe that's just an excuse for saving money... And just look how much they saved in the end! Er, wait

      • They had multiple backups. The on-site generators were one backup. The connection to the grid was another backup. You shouldn't build your generators in a pit next to the ocean.
    • The CEO of Tokyo electric power was warned repeatedly by engineers that they needed off site generators and they needed to build up the flood wall. Both of which would have been very expensive. Neither of which got done.

      Incidentally when all was said and done none of the CEOs got in trouble for ignoring the engineers and the public eventually blamed the engineers not the CEOs who refused to pay for the safety gear.

      I've said it before but the problems with nuclear are social not technical. But they'r
    • by AmiMoJo ( 196126 )

      There were actually backups to those generators. The situation could have been salvaged. They did manage to get emergency pump vehicles in place and water flowing. Unfortunately a valve diverted the water into tanks instead of into the reactor, and they didn't notice because the monitoring equipment was damaged by the earthquake.

    • by gweihir ( 88907 )

      Or to expand on that: Designers of safety mechanisms should not be excessively stupid.

  • Just a reminder (Score:2, Interesting)

    that all nuclear accidents to date were from gen 1 reactors.

    • by dfghjk ( 711126 )

      So?

      Let Elon Musk get involved, that will change quickly.

    • Just a reminder that all nuclear accidents to date were from gen 1 reactors.

      That is, if we're not using the U.S. Department of Energy's formal generational scheme, where gen 2 [wikipedia.org] includes e.g. Chernobyl's reactor that exploded. So, what you mean is that every serious accident happened in older-era reactors built before modern designs with passive safety features.

      • Yes, that's what I mean. And chernobyl was a weird one because they were intentionally driving it into criticality.

      • Chernobyl wasn't an accident. Deliberately operating the reactor outside design tolerances and having it explode doesn't mean the design is inherently unsafe during normal operations.

        Nobody complains about the durability of a car engine if you drive it around with no oil in it.

  • Context (Score:5, Informative)

    by kid_wonder ( 21480 ) <slashdotNO@SPAMkscottklein.com> on Wednesday January 21, 2026 @01:10PM (#65939894) Homepage

    Worth noting: Kashiwazaki-Kariwa Nuclear Power Plant wasn’t offline because it was unsafe to operate, but because Japan rewrote its nuclear rulebook after Fukushima. The post-2011 requirements are much stricter (earthquakes, tsunamis, backup power, security), and it’s taken years to get approvals. Reactor 6 got through first since it’s newer and already had upgrades.

    The restart push is mostly about energy reality: Japan imports most of its fuel, LNG got expensive, and cutting emissions without nuclear is hard. Local opposition is still a factor though, especially given the seismic risks, which is why the rest of the plant is still years away from full operation — if it ever gets there.

    • by AmiMoJo ( 196126 )

      It was unsafe. At the time of the earthquake, most of it was offline because the operator, TEPCO, the same guys running Fukishima Daiichi, had falsified safety check data.

      The design is fundamentally flawed. It is only rated for horizontal acceleration of 4.5m/s in an earthquake, and back in 2007 it experienced 6.8m/s, with some parts of the plant seeing over 20m/s. Some of the waste storage failed too.

      They haven't fixed that, they just claim to have put measures in place to deal with the reactors getting sh

  • by MpVpRb ( 1423381 ) on Wednesday January 21, 2026 @01:22PM (#65939930)

    No, they decided to shut them down, partly for safety concerns, partly for political concerns

  • All the best stuff is made in Japan.

  • Firstly, get out a map, and decide where you can put x-es, where you don't want humans to be ever. Next take an accident with the proportions to even have crumbled the Soviet Union. Though, it's not over yet, because it will keep taking, and taking. Or you can shut off your lights when you leave the room.
  • Tepco cannot afford the first cleanup--who is underwriting the second disaster?
    In 2017, the Japan Center for Economic Research estimated the total cleanup costs to be between 50 and 70 trillion yen ($470 to $660 billion)
    https://en.wikipedia.org/wiki/... [wikipedia.org]

The universe is all a spin-off of the Big Bang.

Working...