Shutting Iran’s oil wells may be straightforward – but the consequences are not | Iran-Gulf Crisis

Summary

The Strait of Hormuz – the narrow waterway through which between 20% and 25% of the world’s seaborne oil normally passes – has been been effectively closed for just over two months. As tensions have escalated, Iran has restricted passage through the Strait, while the US has imposed a naval blockade on Iranian shipping, sharply limiting Tehran’s ability to export crude. On May 3, the US president Donald Trump announced Project Freedom, by which US warships would escort vessels from countries not involved in the conflict through the Strait. But some reports have suggested that Iran has since fired on several ships attempting to transit and the waterway remains effectively closed. The immediate consequences are tankers stranded, prices surging, and Iran rapidly running out of places to store its oil. Analysts now warn that storage could fill within weeks, forcing producers to shut wells altogether. But the deeper story lies far below the surface. Oil wells are not designed to be switched off and on at will. And when they are, the damage can linger long after the crisis has passed. To understand why, it helps to ditch the idea of oil fields as underground lakes. In reality, oil sits trapped inside microscopic pores in rock, typically a hundredth of a millimeter wide, held there by pressure, temperature, and a delicate balance between oil, gas and water. Shutting them down, especially abruptly and for long periods, can alter their internal balance in ways that are difficult, sometimes impossible, to reverse. Production works because the system is in motion. When a well is open, pressure differences drive oil toward the wellbore (a drilled channel connecting the oil reservoir to the surface). Over time, that pressure naturally declines, which is why operators use techniques such as water or gas injection to maintain flow. The key point is that reservoirs are dynamic. They depend on continuous management to remain productive. Shut the well and the movement of the oil stops. The consequences begin almost immediately. One of the first changes occurs in pressure distribution. While shutting down a well can temporarily allow pressure to build back up near the wellbore, the broader reservoir may experience uneven redistribution. In fields that rely on carefully managed injection, where water or gas is pumped in to push oil out, halting operations disrupts that system. The injected fluids can migrate unpredictably, sometimes bypassing oil-rich zones entirely when production resumes. The fluid can chose a different path for movement so it may no longer push the oil out of the reservoir. Then there is the chemistry. Crude oil is not a uniform substance; it contains heavier components such as waxes and asphaltenes — long-chain hydrocarbons and dense, complex molecules that can solidify or precipitate out under changing conditions. Under stable flow conditions, these remain dissolved. But when flow stops and temperatures or pressures change, these components can essentially clog the tiny pores in the rock or the well itself. Once deposited, these materials can restrict flow unless expensive – and not always successful – techniques are used to repair the damage. Water adds another layer of complexity. All reservoirs contain formation water (the naturally occurring water trapped in the rock alongside oil and gas), and in some cases injected seawater. When a well is shut in, water can intrude into zones that previously produced mostly oil. Over time, this “water invasion” can become entrenched, meaning that when production resumes, the well produces far more water and far less oil. Separating and disposing of that water is costly, and in some cases the oil production becomes uneconomic. There are also mechanical risks. The well itself is lined with steel casing and cement, and is designed to operate under certain conditions. Long shutdowns can lead to corrosion, scaling (mineral build-up), or even structural integrity issues. In extreme cases, restarting a well can require significant reworking, akin to reopening a mine that has partially collapsed. Perhaps the most misunderstood aspect is what happens at the scale of the whole oil reservoir over longer periods. Some reservoirs are highly sensitive to pressure changes. If pressure drops too low or fluctuates unpredictably, the rock structure can compact. This compaction reduces the pores available to store and transmit fluids, permanently lowering the field’s production potential. Gas behaviour also matters. In many reservoirs, gas is dissolved in oil under high pressure. When pressure falls below a certain threshold, gas comes out of solution, which forms bubbles that can block flow pathways . If this happens unevenly during a shutdown, it can leave behind pockets of oil that are effectively stranded. All of this helps explain why operators are cautious about shutting in production unless they have to. It is not just a matter of lost revenue during downtime – it’s the risk of losing future production capacity altogether. That said, not all wells suffer equally. Some reservoirs are more resilient. In many cases, particularly in large conventional fields, production can be restored relatively quickly after a shutdown, as seen in past disruptions. But this doesn’t mean the reservoir is unaffected – even when output returns, subtle changes can reduce efficiency, increase costs, or leave some oil permanently unrecovered. In practice, this can mean a reduction in how much oil is ultimately recoverable. Some pockets may become harder to access or uneconomic to produce under normal conditions, even if they remain physically in place. That does not imply the oil is lost forever, but it can shift part of it beyond reach with current technology or prices, effectively lowering the field’s long-term yield. There are environmental risks too. Closure of wells may cut emissions in the short term, but pressure instability can increase methane leakage. Restarting wells often involves flaring and venting, adding further emissions. Over time, water intrusion and reservoir damage can raise the environmental cost per barrel, as more energy is needed to extract less oil. Modern engineering can mitigate some risks through careful planning maintaining minimal circulation, managing pressure, or using chemical treatments. But these measures require time, coordination, and resources, which may not be available in a sudden geopolitical crisis. The broader lesson is that oil production is not easily paused and resumed like a factory assembly line. It is a continuous interaction with a complex natural system. Interruptions especially abrupt, large-scale ones can leave lasting scars beneath the surface, long after the valves are reopened.

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Martin J Blunt; Nima ShokriBy Martin J Blunt; Nima Shokri

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Jun 22, 2026economicUnverifiedIranChina

High oil prices drive a surge in Chinese electric vehicle sales, but charging networks lag behind

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High oil prices drive a surge in Chinese electric vehicle sales, but charging networks lag behind The war in Iran has helped reshape the global electric vehicle market, giving Chinese automakers an opening across the developing world as fuel prices surge The war in Iran has helped reshape the global electric vehicle market, giving Chinese automakers an opening across the developing world as soaring fuel prices push drivers towards electric vehicles, even as charging infrastructure lags behind a wave of imports.

The blockade of the Strait of Hormuz disrupted shipping of about a fifth of the world’s crude oil and liquified natural gas, first hitting Asia — the main destination for the fuels — followed by Africa. This shock accelerated a trend that was already spreading across the developing world.

In April, global exports of Chinese EVs hit a record $9.4 billion, according to an analysis by think tank Ember of Chinese customs data. Shipments surged to countries such as Australia, Brazil and regions like Southeast Asia and East Africa. China exported about 435,000 passenger EVs and plug-in hybrids in May, more than double from a year earlier, according to the Chinese Association of Automobile Manufacturers.

As fuel costs rise, more drivers are switching to EVs to save money, while governments from Laos to Ethiopia are embracing electrification to curb oil imports and reduce costs of fuel subsidies. But faster EV adoption is outpacing the expansion of charging networks.

Governments and state-owned utilities in Africa are taking a leading role in building them — a model analysts say could help other emerging markets, like Asia, speed the shift away from fossil fuels. When a nation lacks sufficient charging infrastructure and EV fleet size, it is a “classic chicken-and-egg problem” regarding what comes first, said Paul Gong, head of UBS bank’s China automotive industry research.

“At that stage, government support for infrastructure could help accelerate adoption,” he said. Fuel shock drives EV use in Asia and Africa Across the developing world, drivers are looking beyond the gas pump. In Southeast Asia, imports of Chinese EVs have surged in Thailand, Laos and the Philippines.

In May, Laos banned the import of fuel-powered vehicles for the rest of 2026 to cut oil import costs and encourage the EV shift. Africa imported around 44,000 Chinese EVs in 2025, a 130% jump from the year before, according to Chinese Commerce Ministry data.

Across Asia and Africa, transport is one of the largest household expenses. Limited public transit, long commutes and a reliance on private vehicles make families vulnerable to volatile fuel prices. In South Africa, transportation accounts for nearly a fifth of household spending, according to a 2024 study by Stellenbosch University in South Africa's Western Cape province.

So, as fuel prices surge, global interest in EVs has been growing, said Mark Wakefield, with the consultancy AlixPartners. One in four new cars sold worldwide last year were electric, according to the International Energy Agency. Global electric car sales are expected to grow further in 2026 and reach 23 million, making up nearly 30% of all cars sold worldwide, according to the IEA’s latest EV outlook.

“In the next five years, we will accelerate (our) overseas expansion,” said Jerry Gan, CEO of Geely Auto, one of China's biggest automakers, at a company event in March as the auto group makes inroad into regions like Southeast Asia including selling EVs.

Chinese automakers supplied around 60% of electric cars sold globally, the IEA said. They have also been targeting Europe, Africa and Latin America. In Vietnam, automaker VinFast also logged stronger sales. Demand from Southeast Asia helped drive a 42% year-on-year increase in the company's January-March quarterly revenue.

On most mornings, Nguyen Thien Bao threads his VinFast electric motorbike through the jammed traffic of Vietnam’s capital Hanoi — ferrying passengers and deliveries. The EV bike has sharply cut his expenses as fuel prices rise. “Before, so much of my income went into fuel,” he said.

“Now, I can actually save some money.” Charging stations aren't keeping up But while EV imports are booming, charging infrastructure is still lagging even as installations have accelerated. Thailand, for instance, has around 4,600 public charging locations to serve more than 424,000 battery EVs and plug-in hybrids, according to the Electric Vehicle Association of Thailand — around one for every 92 vehicles.

The country currently has roughly 12,000 public chargers, the IEA said. Chitsanupong Nuamnorm's solution is to keep his gasoline-fueled Mazda 2 for weekend trips, although the Chinese-made MG4 EV he bought on Feb. 27 — the day before the Iran war began — is saving him a lot of money.

Yutthana Samranwong, a 54-year-old driver in Thailand’s northern Phitsanulok province, says booking online for public charging ports to keep his MG4 EV running is a gamble. “It's a bit of a headache,” said Samranwong, who sometimes works with the Grab ride-hailing and delivery service.

In Bangkok, strained charging networks are prompting some drivers to consider returning to fuel-powered cars. In Malaysia, public fast chargers were up more than 70% in 2025, according to the IEA, after the government rolled out incentives to including a tax break for operators of charging points that meet certain investment criteria.

Indonesia has more than 4,500 public charging stations set up the state-owned power utility PLN, the IEA said. Ethiopia, which has banned non-EV imports, had only around a dozen charging stations as of mid-2025, and the government estimates it needs more than 1,170 stations to meet rising demand.

In the capital Addis Ababa, 40 stations are under construction, according to the state electricity utility. “In developing markets, affordability can accelerate the shift, but the pace of adoption will still depend heavily on infrastructure, power reliability and use case,” said Chris Liu, with the technology research and advisory group Omdia.

State utilities take the wheel to build charging stations In Indonesia, more than 4,500 public chargers have been deployed by its state-owned power utility PLN, the IEA said. African countries also are increasingly turning to state-owned utilities to build EV charging networks, betting public investment can solve one of the biggest obstacles to electric vehicle adoption.

“Utilities are recognizing that electric mobility will become a meaningful source of future electricity demand,” said Ndia Magadagela, co-founder and CEO of Everlectric, a South African commercial EV leasing company. There are around 2,000 public EV charging stations in Africa, with South Africa accounting for the largest share.

State-controlled utility Kenya Power plans to build 44 charging stations within the next year. But building networks of charging stations is difficult in developing markets, according to Omidia's Liu, who said grid connections and maintenance are key issues.

While BYD, for example, is expanding its ultrafast EV charging network in places like Europe, large Chinese automakers typically may have relatively little incentive to build networks outside China, he said. State-owned utilities, therefore, can play a larger role in this, according to Liu, since they are closely tied to a country’s grid planning, electricity pricing and distribution capacity.

“You need charging infrastructure to support an even larger fleet size,” said Gong, the auto analyst from UBS. ___ Olingo reported from Nairobi, Kenya, and Delgado reported from Bangkok. Associated Press writer Aniruddha Ghosal contributed to this report.

___ The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. The AP is solely responsible for all content. Find AP’s standards for working with philanthropies, a list of supporters and funded coverage areas at AP.

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Chan Ho-Him

Shutting Iran’s oil wells may be straightforward – but the consequences are not

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