Japan cuts gas 16% as Hormuz squeeze lifts coal use

Japan’s gas-fired power output fell 16 per cent in June to 17.3 terawatt hours as disruption around the Strait of Hormuz tightened LNG supply and pushed utilities back toward coal. Coal generation rose 4.6 per cent over the month, Bloomberg reported.

For power and fuel traders, the June data move the Hormuz story out of shipping lanes and into dispatch rooms. Scramnews has followed the same shock through floating stockpiles and tanker delays. Japan’s numbers show the strain has reached the grid, where fuel choice turns on cargo timing as much as headline prices.

The price pressure is plain. Asian LNG spot prices are about 70 per cent above pre-war levels, and Japan’s LNG imports from March through June were about 7 per cent lower than a year earlier. Utilities may still prefer gas where they can get it. The near-term test is whether cargoes are available at a delivered cost that beats coal units already sitting on the system.

The move follows a regional pattern. In a Reuters report from May, analysts said Japan and South Korea were already relying more heavily on coal as the Iran war constrained gas availability. Japan’s June figures make that warning look less like a risk scenario and more like operating behaviour.

“The longer this war continues, the more switching we will see.”

— Andre Lambine, power analyst at S&P Global Energy

What the power mix showed

Japan rarely changes its fuel mix sharply without a clear price or supply shock. Gas remains central to the country’s generation fleet, so a drop to 17.3 terawatt hours in one month points to physical tightness as much as buying preference.

US natural gas futures were last at 3.228, up 0.4 per cent over one month, according to yfinance data in the fact bundle. The contrast is useful: the pressure sits in seaborne LNG and delivery risk, not in a broad spike across every gas benchmark.

That leaves traders looking past Henry Hub. Asian buyers are paying a freight and security premium, which makes regional LNG and coal spreads a cleaner read than a generic global gas rally.

Coal benefits because the spare capacity is already installed. Utilities do not need new plants to lean harder on coal; they need to run existing units more often. When LNG cargoes are delayed, rerouted or repriced, coal is the fastest bridge.

Japan’s size in the LNG market adds weight to the signal. Even a modest dispatch shift can alter prompt cargo demand across the basin and change how traders price competition for available supply.

Reuters’ May reporting caught the broader calculation. Asian buyers were facing LNG prices that had risen faster than coal benchmarks. Alexandre Claude, a power and gas analyst cited by Reuters, said coal’s value was increasingly being defined by security rather than economics. Japan’s June dispatch data put numbers behind that argument.

Why traders will watch coal next

The next question is how long the switch lasts. If Hormuz traffic normalizes quickly and spot LNG cools, Japanese utilities can move back toward gas. If disruptions persist into summer, traders may have to price a longer run of coal resilience across Asia.

The signal will travel beyond Japan. The country is often an early read on how North Asian utilities react when LNG tightens. A visible reduction in gas burn from a major importer can reshape assumptions about regional cargo competition and coal demand, especially if other buyers respond the same way.

For now, Hormuz risk is no longer just a freight story. It is showing up in monthly generation data from one of Asia’s largest LNG consumers. That gives coal, gas and utility traders a firmer signal than another headline about tanker delays.