The opinions expressed here are those of the author, a columnist for Reuters.

By Gavin Maguire

LITTLETON, Colorado, May 27 (Reuters) - Many of Asia's largest cities are already gripped by above-normal temperatures that are prompting widespread use of power-hungry air conditioners weeks ahead of the usual peak in summer thermometer readings across the region.

Temperatures in many parts of China, Japan, India, South Korea and Southeast Asia have climbed to well above their long-term averages recently, and look set to remain elevated for the next several weeks, data compiled by LSEG shows.

Such a sustained stretch of hot weather will likely spur a collective climb in air conditioner use, which in turn will place extra strain on power generators that are on the hook to keep electricity supplies flowing.

To ensure round-the-clock power output, utilities across Asia will likely need to step up use of coal and gas-fired power plants, and will trigger drawdowns of coal and gas inventories that will need to be replenished as summer gets into full swing.

Stepped-up competition for power-generating fuels by Asian utilities could ignite fresh strength in global coal and gas markets, which have already been roiled by the U.S.-Israeli war with Iran and stunted ship traffic through the Strait of Hormuz.

HOTTING UP

Millions of households across Asia are already dealing with sharply above-normal temperatures, even though the official meteorological summer only gets underway on June 1 in the northern hemisphere.

Since the middle of May, average temperature readings in Seoul, South Korea, have held around 13% above the long-term average, LSEG data shows, sparking "extreme heat warnings" from the Korea Meteorological Administration (KMA).

Such warnings are triggered when either the daily maximum perceived temperature reaches 38 degrees Celsius (100.4 degrees Fahrenheit) or the daily high exceeds 39 C (102 F).

In Shanghai, temperatures since mid-May have held around 12% above normal, while in Tokyo readings have averaged around 10% above normal.

Extreme heat readings have also been registered across India, with several towns recording readings above 40 C (104 F), which drove people to seek shelter in air-conditioned homes and buildings.

UNDER PRESSURE

With well over a billion people impacted by the recent heat waves, power firms are already under strain as they try to lift generation to keep up with the elevated power demand.

Air-conditioning systems are notoriously power-intensive, but have become increasingly popular across South and Southeast Asia as rising temperatures and high humidity levels force households to prioritise comfort over electricity conservation.

Indeed, due to the rapid build-out of living space across the hottest parts of Asia, Africa and the Middle East, the share of global dwellings with air-conditioning systems is expected to jump from around 36% in 2022 to 60% by 2050, according to the International Energy Agency (IEA).

That surge in demand for space cooling is arguably placing an even larger strain on global power networks than the data center boom, which is concentrated mainly in regions with more developed power networks that can more easily accommodate increased demand loads.

Across Asia, power firms are already struggling to meet the demand from homes and businesses during the current heat wave, with authorities in Vietnam, the Philippines and India all recently issuing power output warnings.

And if the current stretch of hot and humid weather stretches into the peak summer period, further warnings of power failures and calls for cuts to power use can be expected.

COAL-HEAVY POWER FOUNDATIONS

Despite steep growth in generation from solar and wind farms in recent years, over half of Asia's electricity supplies continue to come from fossil fuel power plants.

Coal-fired plants generated around 52% of Asia's utility-supplied electricity in 2025, and will remain the backbone of the region's power system for the foreseeable future.

Natural gas plants account for around 10% of Asia's electricity supplies, and had been expected to take up a growing generation share going forward, especially in wealthier economies where outdated coal plants are due to be closed down.

However, volatility in natural gas and liquefied natural gas (LNG) prices and supplies in recent years has sparked a sharp slowdown in the pace of gas power capacity development, and means that coal-fired plants will likely continue to bear the brunt of Asia's power needs for the near term at least.

That in turn means that upturns in coal import orders from Asian utilities can be expected heading into the peak summer months, which should elevate coal prices and put further upward pressure on regional and global energy costs.

Additional demand for natural gas and LNG can also be expected across Asia, especially in power systems with limited alternatives and where power consumption looks set to remain elevated due to above-average temperatures.

Overall, this means that the current and expected hot spells across Asia have the potential to further tighten global coal and gas markets this summer, and exacerbate the energy shocks already stemming from the U.S. and Israeli war against Iran.

The opinions expressed here are those of the author, a columnist for Reuters.

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