US President Donald Trump has issued a direct ultimatum to Iran: reopen the Strait of Hormuz by 8pm Eastern Time in the United States on Tuesday, April 7 (midnight GMT on April 8), or face the destruction of national power plants and bridges.

This echoes an earlier March 21 ultimatum in which he threatened to attack Iran’s power plants – “the biggest one first” – if the strait was not fully reopened within 48 hours.

President Trump has since extended that deadline several times, citing progress in negotiations he claims the US is having with Iran to end the ongoing war. Iran denies it is holding direct talks with the US.

While Trump has made grand statements such as “they’re going to lose every power plant and every other plant they have in the whole country”, he has not mentioned specific targets.

The US president has also threatened to destroy the country’s bridges. Over the weekend, a US-Israeli strike hit the B1 bridge in the city of Karaj, west of Tehran. The major highway link, described as the tallest bridge in the Middle East, had been scheduled to be inaugurated soon. It sustained significant damage in the strike.

Legal experts say that targeting civilian sites amounts to “collective punishment”, which is prohibited under the laws of war.

Where are Iran’s power plants?

Iran operates hundreds of power plants which, together, form one of the largest electricity systems in the Middle East, supplying energy to 92 million people.

Most of the country’s power plants are close to major population centres and industrial hubs. The majority of Iran’s population lives in the western half of the country, with Tehran, Mashhad and Isfahan the three largest cities.

Iran has a mixture of gas, coal, hydro, nuclear and oil-fired power plants, but most are gas-fired. In the north and centre of the country, clusters of gas-fired plants supply electricity to the country’s largest population centres, including Tehran, Karaj, Isfahan and Mashhad.

Another major concentration of power plants lies along the Gulf coast. These plants sit close to major gasfields and ports, allowing large thermal stations to run on abundant natural gas.

The coast is also home to the Bushehr Nuclear Power Plant, Iran’s only nuclear power facility, which has a capacity of 1,000MW. The US and Israel have repeatedly hit this nuclear power plant, raising risks of radioactive contamination far beyond Iran’s borders, the state-run Atomic Energy Organisation of Iran (AEOI) has warned.

Iran also operates a handful of hydropower dams concentrated along the Karun River, the country’s most important source of hydroelectric generation.

Electricity generated from all these plants is fed into a national transmission network operated by Iran Grid Management Company, which distributes power to cities, industries and homes across the country.

The map below shows all of Iran’s power stations with a capacity of 100MW or more.

A 100MW power plant can typically supply electricity to roughly 75,000 to 100,000 homes, depending on consumption patterns.

Iran’s largest power plant by capacity is the Damavand Power Plant located in the Pakdasht area, roughly 50km (31 miles) southeast of Tehran, with a capacity of some 2,900MW, enough to power more than two million homes.

Which are Iran’s most important power plants?

Iran’s largest power plants include:

• Damavand (Pakdasht) Power Plant – Near Tehran.
  Fuel: Natural gas (combined-cycle).
  Capacity: 2,868MW.
• Shahid Salimi Power Plant – Neka, along the Caspian Sea coast.
  Fuel: Natural gas.
  Capacity: 2,215MW.
• Shahid Rajaee Power Plant – Near Qazvin.
  Fuel: Natural gas.
  Capacity: 2,043MW.
• Karun-3 Dam – Khuzestan Province.
  Fuel: Hydropower.
  Capacity: 2,000MW.
• Kerman Power Plant – Kerman.
  Fuel: Natural gas.
  Capacity: 1,912MW.

Other smaller but strategically important power plants include:

• Ramin Power Plant – Ahvaz, Khuzestan.
  Fuel: Gas.
  Capacity: 1,903MW.
• Bushehr Nuclear Power Plant – On the Gulf.
  Fuel: Nuclear.
  Capacity: 1,000MW.
• Bandar Abbas Power Plant – Near the Strait of Hormuz.
  Fuel: Oil.
  Capacity: 1,330MW.

How does Iran generate its electricity?

Iran’s electricity system relies heavily on large thermal power plants fuelled by natural gas. The country has one of the world’s largest natural gas reserves, and this fuel forms the backbone of its power system.

In 2025, 86 percent of Iran’s electricity came from natural gas.

Oil-fired plants provide a smaller share, generating roughly seven percent of electricity. Some power stations switch to diesel or fuel oil when natural gas supplies are tight, especially during winter demand peaks.

Hydropower accounts for about five percent of electricity. Large dams on rivers such as the Karun River generate power by using flowing water to spin turbines.

Nuclear energy contributes around two percent of the country’s electricity, mainly from the Bushehr Nuclear Power Plant, Iran’s only operational nuclear reactor.

Renewables such as solar and wind play a very small role, together accounting for less than one percent of electricity generation.

Overall, more than 90 percent of Iran’s electricity comes from fossil fuels, making it one of the most gas-dependent power systems in the world.