For more than a decade after the Fukushima accident, Japan’s nuclear industry existed in a kind of limbo. Reactors were shut down, politicians spoke cautiously about reducing dependence on nuclear energy, and many people assumed the country would gradually move away from atomic power.
Yet while public attention remained focused on reactor restarts and safety debates, Japan’s long-term energy strategy was evolving. The clearest evidence came with the release of the country’s 7th Strategic Energy Plan, which outlines how Japan expects to power itself through 2040.
The plan targets roughly 20% of Japan’s electricity from nuclear power by 2040, more than double the share seen in recent years. It also supports extending reactor operating lives and replacing retired plants with next-generation designs. Viewed against the political atmosphere that followed the Fukushima accident, the shift is striking. In 2012, the discussion centered on how quickly Japan could reduce its reliance on nuclear energy. Today, government planning assumes nuclear power will remain part of the system for decades.
The change reflects the realities Japan encountered after most of its reactors went offline.
Renewable energy expanded rapidly. Solar installations spread across the country, and Japan became one of the world’s largest solar markets. At the same time, electricity demand did not disappear. Manufacturers still required stable power. Urban centers continued to consume vast amounts of electricity during summer heat waves. Digital infrastructure expanded. Data centers multiplied.
To bridge the gap, Japan relied heavily on imported fossil fuels, particularly liquefied natural gas. By the early 2020s, the country had become one of the world’s largest LNG importers. Global energy shocks—from supply disruptions to geopolitical conflicts—quickly translated into higher fuel costs and higher electricity prices at home. Carbon emissions remained stubbornly difficult to reduce.
Those pressures have only intensified. Artificial intelligence is increasing electricity demand around the world. Governments are competing to attract semiconductor manufacturing and advanced industries. Energy security has moved from a technical policy discussion to a national strategic concern. Japan’s Green Transformation (GX) strategy aims to reduce emissions while maintaining economic competitiveness, a goal that requires large quantities of reliable low-carbon electricity.
Whether Japan can achieve its nuclear ambitions remains an open question.
One of the lasting consequences of the Fukushima accident was the creation of the Nuclear Regulation Authority, designed to operate independently from both political leaders and the nuclear industry. Restart approvals often take years. Utilities argue the process is slow and costly. Regulators maintain that thorough reviews are essential to rebuilding public trust.
That tension now sits at the center of Japan’s energy policy. The government can set targets, but it cannot instruct regulators to accelerate approvals. Utilities can invest billions of yen in upgrades, but local communities still expect convincing evidence that plants can operate safely. Every restart requires technical reviews, regulatory approval, and public acceptance.
Public opinion has shifted, though cautiously. Support for restarting existing reactors has increased as concerns about energy costs, energy security, and climate change have grown. Views become more divided when discussions turn to new construction. The memory of the Fukushima accident continues to shape how many Japanese evaluate the benefits and risks of nuclear energy.
For that reason, Japan’s energy strategy today looks very different from the one imagined immediately after 2011. The central debate is no longer whether nuclear power has a role in the country’s future energy mix. Policymakers have largely answered that question. The challenge now is determining how much nuclear capacity can realistically return, how quickly it can happen, and whether it can keep pace with the country’s economic, environmental, and energy security goals.
Japan’s latest energy plan offers a clear direction. Reaching that destination may prove considerably more complicated.