Informing Nuclear Diplomacy with Iran

Apr 9, 2014
B. Rose Huber
Woodrow Wilson School

The construction of a nuclear reactor near the Iranian city of Arak is one of the major issues being tackled in the negotiations between Iran and six global powers this week in Vienna.

Some among the P5+1 group of powers—China, France, Germany, Russia, the United Kingdom and the United States—fear the Iranian reactor, which is currently under construction, could produce a large supply of plutonium, which could be used to build nuclear weapons.

Changing the reactor's fuel, however, could reduce such a threat, according to a team of experts at Princeton University's Woodrow Wilson School of Public and International Affairs. The researchers, all from the Program on Science and Global Security (SGS), propose their technical modifications—including changing the operating power of the reactor—in the April issue of Arms Control Today.

"The changes we suggest could dramatically reduce the reactor’s production of plutonium while maintaining the reactor's performance for peaceful applications," said co-author Frank von Hippel, a founder of SGS, and professor emeritus of public and international affairs.

As part of the first phase agreement reached by the P5+1 and Iran in November 2013, Iran agreed to halt construction on the Arak reactor during the six-month period of that deal but maintained the need to complete and operate the reactor to produce medical isotopes, which are used in nuclear medicine to diagnose many diseases. In February 2014, Ali Akhbar Salehi, the head of the Atomic Energy Organization of Iran, said that Iran could consider design changes to the Arak reactor that would “allay the worries and mitigate the concerns” of the international community.

The current U.S. position is to propose that Iran scrap the existing Arak reactor and build a light-water research reactor instead.

"A light-water reactor produces much less plutonium," said Zia Mian, a research scientist with SGS. "However, Iran sees the Arak reactor as a hard-won achievement, and seems unwilling to abandon it."

The Princeton team urges that Iran dramatically reduce its potential plutonium output by converting the reactor from using natural uranium fuel to low-enriched uranium fuel. This would greatly reduce the quantity of U-238 in the fuel that is turned into plutonium in the reactor by neutron absorption. With low-enriched fuel, the reactor power could be reduced without loss of performance and so further reduce plutonium production.

"These measures require Iran to make a different kind of fuel for Arak than what they currently plan," said Alexander Glaser, assistant professor at the Wilson School and Department of Mechanical and Aerospace Engineering at Princeton. "But they would meet Iran's needs and address the concerns of the international community as reflected by the P5+1.”

"The steps we describe are technically feasible and would not reduce Arak's usefulness for civilian purposes. They provide a sound basis for resolving one of the key points of contention in the talks on Iran's nuclear program," said Ali Ahmad, a research fellow in nuclear technology policy, who performed the computer calculations that underlie the Princeton team’s proposal.

The article, "A Win-Win Solution for Iran's Arak Reactor," was published in the April issue of Arms Control Today, a monthly journal published by the Arms Control Association. It is available upon request.

CONTACT: B. Rose Huber | 609-258-0157 (office) | 609-619-7097 (cell)