Hot July: Southeast Asia Hit by Rare Persistent Heat Wave
Since July 2026, Southeast Asia has experienced rare persistent high temperatures. Temperatures in Laos, Vietnam, Thailand, Cambodia and other countries have repeatedly exceeded 40°C, reaching 44°C in some areas. Extreme heat directly drove a surge in cooling electricity demand from households and businesses, compounded by industrial production recovery, pushing regional power loads to new highs. According to the latest data from the ASEAN Centre for Energy (ACE), in the last week of July, total electricity demand in six Southeast Asian countries (Indonesia, Malaysia, the Philippines, Singapore, Thailand, Vietnam) rose 12% year-on-year to the highest level for that period on record.
Power Spot Prices Surge
The surge in demand quickly transmitted to the spot electricity market. In Vietnam, for example, the average clearing price in the southern wholesale electricity market on July 29 reached USD 85 per MWh, up 38% from the June average, the highest since January 2025. Data from the Thailand Power Trading Center shows that spot prices during peak hours on July 28 soared to USD 120 per MWh, up nearly 50% year-on-year. Spot prices on the Philippines' Luzon grid exceeded USD 150 per MWh, forcing the energy regulator to activate a price cap mechanism (USD 150 per MWh).
In Laos, while domestic electricity prices are relatively stable, as a regional power exporter, the Lao National Power Company (EDL) raised export prices to Thailand and Vietnam. According to an EDL insider, export prices to Thailand were raised 15% in July, with monthly export revenue expected to increase by about USD 20 million. Laos's grid interconnection advantage was highlighted during this heat wave; although hydropower resources were affected by drought, early rainy season precipitation still supported some export capacity.
Cause Analysis: Multiple Factors Combined
- Extreme Weather: In July, Southeast Asia was affected by an anomalously strong subtropical high, with high temperatures lasting long and covering a wide area, and nighttime temperatures not dropping, keeping cooling demand high around the clock.
- Insufficient Hydro Output: Major hydropower countries like Laos and Vietnam experienced drought in prior months, with low reservoir levels reducing hydro output. Although the rainy season started in July, initial precipitation provided limited replenishment, and hydro output recovered slowly, forcing thermal and gas-fired power to increase.
- Rising Natural Gas Costs: Global natural gas prices have been volatile upwards since June, with Asian LNG spot prices breaking USD 12 per MMBtu in mid-July, raising the marginal cost of gas-fired power. Countries reliant on natural gas for power generation, such as Thailand and Indonesia, saw power costs directly affected by international gas prices.
- Coal Power Constraints: In some countries, aging coal-fired units or environmental policy restrictions prevented rapid output increases. For example, some old coal plants in the Philippines were shut down due to failures, exacerbating supply shortages.
Impact and Outlook
The price surge has put pressure on economies and livelihoods across the region. The Federation of Thai Industries stated that high electricity costs will squeeze manufacturing profits, especially for large consumers like aluminum smelting and chemicals. In Vietnam, households face a projected 20-30% increase in monthly electricity bills due to tiered tariff adjustments. To ease the pressure, governments have taken measures: Vietnam's Ministry of Industry and Trade requested the grid to increase power purchases from Laos and China; Thailand's Ministry of Energy announced a temporary reduction in excise tax on diesel power generation; the Philippines implemented stricter price caps on the spot market.
Looking ahead, meteorological agencies predict that the heat wave in Southeast Asia will continue until mid-August, keeping electricity demand high. However, increased rainy season precipitation is expected to gradually improve the hydropower situation, thereby easing thermal power pressure. For Laos, as the rainy season deepens, hydropower output is expected to strengthen, and export capacity will further expand, allowing continued benefit from high regional prices. In the long term, this heat wave once again highlights the vulnerability of Southeast Asia's power grid, and calls for accelerating renewable energy and energy storage deployment are growing.
Energy spot price alert: Investors should closely monitor spot price fluctuations in the Southeast Asian electricity market, especially in Vietnam, Thailand, the Philippines, and the dynamic of Laos's power export prices. It is recommended that relevant enterprises use forward contracts to lock in costs or focus on investment opportunities in energy storage and energy efficiency management.
