Japan Just Scrapped a $9 Billion Nuclear Reactor That Never Really Worked

The Monju nuclear reactor. (Image: Nife/Wikimedia)
The Monju nuclear reactor. (Image: Nife/Wikimedia)

The government of Japan has decided to decommission the experimental Monju nuclear reactor, which worked for just 250 days out of its total 22-year lifespan.

Located in Japan’s Fukui Prefecture, the sodium-cooled fast reactor has been mired in controversy since construction began in 1986. The reactor came online in April 1994, but a major fire sparked by a sodium leak forced a shutdown. After a long delay, the plant was restarted in May 2010, but another accident involving dropped machinery shut it down yet again. As of June 2011, the Monju plant has only generated a single hour’s worth of electricity since it was first tested back in the 1990s.

The experimental fast-breeder reactor, once dubbed the “dream reactor,” was designed to produce more plutonium than it consumes, thus minimizing the amount of nuclear waste. It was a good idea in principle, but accidents and design flaws prevented the reactor from achieving full success. The plant, which cost $9 billion to design and build, would have required $4.6 billion in safety upgrades over the next 30 years to make it work again. “We have decided to decommission Monju because restarting it would require significant time and cost,” Chief Cabinet Secretary Yoshihide Suga told the Associated Press.


The government says it will cost $3.2 billion to fully decommission the facility. The spent nuclear fuel will be removed from the reactor in 2022, and the entire structure will be dismantled by 2047.

Unswayed by this sad episode, Japan still plans to develop fast reactors that reprocesses spent fuel and reuse valuable plutonium and uranium. “We will make full use of the highly valuable knowledge and expertise acquired at Monju as we move forward with fast reactor development...first by concentrating on creating a strategic road map,” said Japan’s Industry minister Hiroshige Seko in the Japan Times.

The decision to dismantle the plant has triggered understandable frustration, both among those who are skeptical of nuclear power following the Fukushima nuclear disaster in 2011, and those who are worried about the associated loss in subsidies and jobs as a result of the closure. Locals are also worried about the dismantling process, citing safety concerns.

[Japan Times, Associated Press via CTV]


George is a senior staff reporter at Gizmodo.

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Really...Nuclear is the way forward for high-power production. Yes...mass solar/wind farms would be even better...but the “failure” of this plant isn’t a failure.

First, it was an experimental reactor to begin with...a science experiment that they hoped would be viable...and it yielded LOTS of viable data and results (aside from electricity).

People ballyhoo* the danger of nuclear plants; especially here in the U.S....without realizing that we haven’t built a reactor since 1996....and the average age of reactors in the US is thirty-five years. https://www.eia.gov/tools/faqs/faq.cfm?id=228&t=21

Think about that for just a second. How many of us would consider a 20-35 year-old car, using safety technology from 30-40 years ago “safe”...basically none of us. (Source: I daily drive a ‘65 Ford and my friends think i’m insane because it doesn’t have 3-point seat belts, air-bags, anti-lock brakes, etc.)

But...because we’re scared of the design safety of these 20-50 year old cars reactors we refuse to build new ones using safety technology and lessons learned from around the globe.

*I was challenged to use that word today. So HA!