On April 3, 2026, Ikeda Onsen in Gifu Prefecture closed due to heavy oil price surges of nearly 200% caused by Middle East supply disruptions from the US-Iran war. Similar closures and operating hour reductions occurred across Aomori, Hyogo, and Osaka prefectures, highlighting Japan's acute vulnerability to energy import disruptions.

Deep Analysis

Event Essence

The US-Iran military conflict escalated sharply, increasing shipping risks in the Strait of Hormuz, through which about one-fifth of global oil trade passes. Japan, importing ~90% of its crude oil from the Middle East, faced immediate price spikes: Brent crude exceeded $110/barrel, JKM LNG prices rose over 80% cumulatively since late February 2026, and domestic spot electricity prices doubled during peak hours. LNG stockpiles fell to just 2–3 weeks of supply. The Japanese government responded by releasing oil reserves (80 million barrels in March, 36 million in April), temporarily relaxing coal power plant restrictions, and accelerating long-term LNG procurement negotiations with the US, Qatar, and Australia. Simultaneously, the debate over restarting idled nuclear reactors intensified, with public support rising due to cost-of-living pressures rather than renewed confidence in nuclear safety.

Economic Impact Points

Surge in Feedstock Costs for Japan's Refining and Petrochemical Sector

The heavy oil price increase directly impacted industrial heat supply for hot springs and manufacturing. Refined product prices rose, with regular gasoline retail prices approaching historical highs. Logistics, taxi, and agricultural transport costs increased significantly, pressuring downstream margins. Japan's petrochemical feedstock naphtha, derived from crude, also faced cost escalation, squeezing olefin and aromatics production profitability. The government may expand fuel subsidy programs to prevent inflation from reigniting.

LNG Procurement Crunch and Long-Term Contract Restructuring

With about 11% of Japan's LNG transiting the Strait of Hormuz and stockpiles lasting only 2–3 weeks, power companies like TEPCO, Kansai Electric, and Chubu Electric face acute supply risks. Japanese firms are shifting from spot to long-term LNG contracts to stabilize pricing, but competition from other Asian buyers intensifies. Meanwhile, deployment of high-efficiency combined cycle gas turbines (CCGT) by Mitsubishi Heavy Industries and Hitachi offers marginal efficiency gains but cannot reduce import dependency. The energy transition is forcing Japan to balance near-term security with long-term decarbonization goals.

Nuclear Restart as a Cost-Stabilizing Imperative

After Fukushima, Japan's nuclear share dropped from ~30% to near zero. Since 2023, METI has pushed to maximize use of safety-cleared reactors and extend lifespans. As of 2026, some units have restarted, but earthquakes (e.g., April 20 magnitude 7.7 off Sanriku) heighten public safety concerns. Despite this, polls show rising support for limited nuclear restarts due to rising electricity bills. Kansai Electric states that without stable nuclear output, exposure to fuel price volatility remains high, ultimately affecting end-user rates. Nuclear power is seen as essential to stabilize base-load electricity costs and reduce reliance on volatile LNG imports.

Hydrogen and Energy Storage as Strategic Geopolitical Hedges

Japan's Basic Hydrogen Strategy (2017) aimed to commercialize hydrogen power generation by ~2030, but high costs and lack of infrastructure have hindered progress. The US-Iran war has elevated hydrogen's strategic importance as a tool to escape fossil fuel geopolitical risks. Recent METI documents propose a complete hydrogen chain from production to mobility. Toyota advances fuel cell vehicles, Kawasaki Heavy Industries develops liquid hydrogen carriers, and JERA tests ammonia co-firing. However, NEDO estimates most hydrogen projects remain unprofitable without subsidies. The short-term contribution is limited, but hydrogen remains a key long-term option for Japan's energy independence.