This weekend, Japan re-entered the nuclear age. A reactor at the Ohi nuclear power plant was reactivated on Sunday, the first power plant to go back online since the nation closed all its reactors in the wake of the Fukushima crisis over a year ago.
The reactivation didn’t pass without controversy, or — unusual in an infamously orderly nation — without protest. According to the Associated Press, tens of thousands of people clamored outside Prime Minister Yoshihiko Noda’s home last Friday, chanting “No to nuclear restarts.” Noda, who ordered the Ohi reactor be switched on, said that it was needed to sustain Japan’s energy supplies. Before the tsunami, nuclear energy powered approximately 30% of Japan’s power.
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At the plant itself, located on Japan’s western coast near the city of Kyoto, police were called in to rein in hundreds of demonstrators. Taisuke Kohno, a 41-year-old musician, planned to stay at the plant day and night. “It’s a lie that nuclear energy is clean,” he told the Associated Press. “After experiencing the nuclear bombing of Hiroshima and Nagasaki, how can Japan possibly want nuclear power?”
However, without the reactors, the country faces a serious power shortage the very real possibility of blackouts in some regions. Since the Fukushima plant forced the evacuation of thousands of people last year, the government has started looking for more reliable energy options, including renewable sources.
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The Ohi plant, has not been operating since it was shut down last year and is expected to help power the region’s cities. All of Japan’s active reactors have been offline since May 5, when the government decided to institute safety checks.
Kansai Electric Power Company, which operates Ohi, has not made a public statement other than the message on its website explaining that a nuclear reaction was restarted Sunday afternoon. From the AFP’s latest accounts, the reactor finally managed to reach a self-sustaining reaction, and is expected to start delivering electricity Wednesday.
Erica Ho is a contributor at TIME and the editor of Map Happy. Find her on Twitter at @ericamho and Google+. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.