Japan's fifth-biggest utility turned on the switches at one of its nuclear reactors on Tuesday, a momentous and fraught occasion for a country still grappling with the aftershock of a deadly nuclear meltdown four years ago.
Kyushu Electric Power Company's Sendai plant, located in the southern Kagoshima prefecture, is the first to come back online since Japan issued new safety requirements in 2013.
Japan's 48 functioning reactors have largely been shut since the catastrophe at Tokyo Electric Power Company's Fukushima Daiichi plant in 2011, one of the world's worst nuclear disasters.
Kyushu's Sendai reactor is one of at least 25 expected to restart over the course of the next decade as Prime Minister Shinzo Abe aims for nuclear power to generate 20-22 percent of the country's electricity by 2030, compared to 30 percent before the nuclear closures. Another 20 reactors are in various stages of the restart process, according to the Nuclear Energy Institute.
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Abe's ruling Liberal Democratic Party (LDP)—a group that's almost continually been in power since 1955)—has traditionally viewed nuclear power as a means of energy independence.
Tuesday's restart has far-reaching consequences for Japan's politics and economy. Here are the key issues: