Japan badly needs sources of energy. By closing the loop on its nuclear fuel cycle, Japan aims to reuse, recycle and produce fresh fuel for its 54 reactors.

Image Monju is 60 miles from Kyoto, a city of 1.5 million people. Credit... The New York Times

“Monju is a vital national asset,” said Noritomo Narita, a spokesman here in Tsuruga for the reactor’s operator, the government-backed Japan Atomic Energy Agency. “In a country so poor in resources, such as Japan, the efficient use of nuclear fuel is our national policy, and our mission.”

Critics have been fighting the project since its inception in the 1970s. “It’s Japan’s most dangerous reactor,” said Miwako Ogiso, secretary general of the Council of the People of Fukui Prefecture Against Nuclear Power. “It’s Japan’s most nonsensical reactor.”

After promises of safety upgrades, as well as lavish subsidies and public works, the government has wooed local officials into allowing a restart of the reactor. In Fukui, the government had ready allies: with 14 nuclear reactors, it is Japan’s most nuclear-friendly prefecture. (Fukushima, in second place, has 10 reactors.)

Monju was reopened in May 2010, and just three months later, the 3.3-ton fuel relay device fell into the pressure vessel when a loose clutch gave way. In the two decades since the reactor started tests in 1991, the atomic energy agency has managed to generate electricity at the reactor only for one full hour.

In Monju, Japan is pursuing a technology that most countries have long abandoned. Decades ago, a handful of countries, including the United States, started exploring similar programs. But severe technical difficulties, as well as fears about the weapons-grade plutonium that the cycle eventually produces, have led most countries to scrap their programs.

But Japan has remained staunchly committed to the Monju project. The government of Prime Minister Naoto Kan has shielded it from the deep cuts in spending that it has required of other national projects since it came to power in September 2009.