Iranian Centrifuges

Gholamreza Aghazadeh, former head of the Iranian Atomic Energy Organization, recounts: “Our machines frequently broke down during the early days of the program. A study revealed that clusters of microbes, unintentionally left by technicians’ hands during centrifuge assembly, were to blame. This small quantity of microbes was enough to destabilize the rotation and destroy the machine. By destruction, we mean the machine was reduced to powder.”

These challenges led Iran to develop a new type of centrifuge, the IR-2, based on the Pakistani second-generation P2 model. A rotor made of ultra-strong steel allowed faster spinning and increased enrichment capacity while reducing the risk of destruction. However, such steel was difficult to produce. Iran then created its own model, replacing the steel rotor with carbon fiber — a material remarkably strong for its weight.

In September 2009, the Atomic Energy Organization of Iran (AEOI) announced that its scientists had succeeded in producing a new, more efficient generation of centrifuges.

Slowed Production

In late February 2010, during a White House briefing, senior administration officials claimed they had evidence that Iran was struggling to maintain its enrichment equipment. Thousands of centrifuges installed at Natanz, the main enrichment site, were not spinning. The Obama administration said Iran was only producing 100 grams of enriched uranium per day and would still need several years to build a bomb.

Technical issues or sabotage? In 2008, President George Bush, after denying a secret Israeli request for bunker-busting bombs to destroy the underground Natanz facility, reportedly authorized covert sabotage operations to derail Iran’s suspected nuclear weapons development.

The possibility of sabotage was reinforced in November 2010 when reports emerged of a computer virus called STUXNET that allegedly targeted centrifuge operations by disrupting their rotational speeds. The IAEA observed that Iran briefly suspended enrichment after electrical malfunctions, though it was unclear if the virus was responsible. Soon after, on November 29, two nuclear scientists were attacked with bombs by assailants on motorcycles. One was killed (the third in two years) and the other injured. Authorities blamed Mossad and the CIA.

Despite the expertise gained by Iranian engineers, many months of difficult research and development were still needed before these centrifuges could be deployed on a large scale. Their use was expected to multiply enrichment capacity by four.

In January 2013, Tehran informed the International Atomic Energy Agency (IAEA) of its intention to use IR-2m centrifuges in Unit A-22 of the Natanz enrichment facility. This newer generation of centrifuges, designed for low-level enrichment under 5%, was not intended for the Fordo facility. Implementation was to be gradual, with a first batch of 180 IR-2m centrifuges reportedly installed in February 2013.

Before stepping down following the election of President Hassan Rouhani, the head of Iran’s nuclear program, Fereydoun Abbasi Davani, stated on August 17, 2013, that Iran had around 18,000 centrifuges, more than 10,000 of which were operational — figures confirmed by the IAEA. About 1,000 of these, far more efficient, were second-generation models.

After the July 14, 2015 Iran Nuclear Deal

One of the clauses in the agreement significantly limited Iran’s enrichment capacity, requiring the country to forgo its most advanced centrifuges. For four years, IAEA inspections showed Iran complied with the terms. That changed after August 2019. Under heavy economic sanctions imposed by the Trump administration, which withdrew from the deal, Iran announced it was restarting its advanced centrifuges, while remaining under IAEA monitoring and stating that the move was reversible.

June 13, 2025

A 12-Day War: U.S. Bombings on Fordo

Is Iran’s uranium enrichment program aimed at building a nuclear weapon? A much smaller country, North Korea, detonated its first nuclear bomb in 2006. Two decades later, what lies behind accusations of Iran hiding a nuclear weapons program? Reportedly, 400 kg of uranium have been enriched to 60%, still 30% below the 90% required for a bomb. But why enrich 400 kg if they have no civilian use?

By starting a war with Iran, Israeli President Benjamin Netanyahu realized an old ambition. He pushed the Gaza conflict and the Palestinian statehood debate — which he opposed — into the background. Two days later, U.S. President Donald Trump used deep-penetration bombs to strike enrichment facilities at Natanz and Fordo, before halting the bombings on June 25. Whether the sites withstood the attacks remains unknown.

Following the U.S. withdrawal in 2018 from the 2015 Vienna Agreement limiting Iran’s nuclear activities, Iran had shown restraint, maintaining cooperation with the IAEA and allowing inspections of Natanz, Fordo, and other sites.

Talks between U.S. and Iranian officials are reportedly under consideration. Meanwhile, cooperation with the IAEA remains suspended.