Go to Home Page
  Key Issues Nuclear Weapons Issues Proliferation Nuclear Fuel Cycle

The Nuclear Fuel Cycle

Introduction: The nuclear fuel cycle is a series of steps that produce fuel for nuclear power reactors, which in turn generate electricity. The production of nuclear fuel can serve both peaceful and military purposes. The dual-use nature of the fuel cycle allows for the creation of civilian nuclear power as well as the production of weapons-grade material for nuclear weapons.

Printer Friendly





The proliferation risks associated with fuel cycle technologies have been known since the dawn of the Nuclear Age in the 1940s. The Baruch Plan of 1946 argues for the peaceful use of nuclear energy and ambitiously proposes international “complete managerial control of the production of fissionable materials in dangerous quantities.” Recent developments across the globe have refocused attention of the international community on ways to control the proliferation sensitive parts of the nuclear fuel cycle. Highlights of these recent developments include:

  • In January 2003, North Korea announced its withdrawal from the nuclear Non-Proliferation Treaty (NPT) under which it had secretly acquired a nuclear-weapons capability.
  • In June 2003, the International Atomic Energy Agency (IAEA) declared Iran’s failure to fully declare all of its nuclear activities and materials, including the acquisition of centrifuge technology that can be used for uranium enrichment.
  • In February 2004, the Pakistani nuclear scientist Abdul Qadeer Khan confessed the existence of a global nuclear black market that supplied technology and weapon designs to Iran, Libya and North Korea.

Related to the challenges posed by these recent developments is the ongoing problem of poorly secured fissile material in several countries, most notably in Russia and Pakistan, which increases the likelihood of terrorist acquisition and use. The Lugar Survey on Proliferation Threats and Responses of June 2005 highlights the need to prevent fissile material theft by terrorists.

Nuclear Fuel Cycle Technology: The nuclear fuel cycle is the complex process of preparing uranium for fuel use in nuclear power reactors, also called the “front end” of the fuel cycle. The “back end” of the fuel cycle refers to the storage, reprocessing and disposal of the uranium after its use in the reactor.

Uranium and plutonium, also called fissile materials, are the two main materials used to produce nuclear weapons. Uranium occurs naturally, while plutonium is produced as a by-product in nuclear power reactors.

The dual-use nature of uranium for both peaceful and military purposes is a major proliferation problem associated with the nuclear fuel cycle. Uranium undergoes a series of steps until it is usable in nuclear power reactors. Part of this preparation involves a highly complicated enrichment process to increase the proportion of the isotope U-235 in uranium. In a nuclear chain reaction, U-235 has the propensity to split and release energy, a process called fission. Different methods of enrichment exist; but the use of gas centrifuges is one of the most common. For use in civilian reactors, uranium has to be enriched to 2-3%, resulting in low-enriched uranium (LEU). Enrichment technology can also serve to produce weapons-gradable uranium, which contains 90% of U-235, known as highly-enriched uranium (HEU).

After its use in nuclear power reactors, the uranium, which includes 1% plutonium as a by-product, is taken out of the reactor, stored, and possibly reprocessed to separate the fuel from nuclear waste. There are several proliferation concerns about the management of used uranium and the back end of the fuel cycle. During reprocessing, plutonium is separated from the uranium fuel, which is highly radioactive. While the extracted plutonium can be re-used as reactor fuel for civilian purposes, it can also serve as fissile material for nuclear weapons. Only 8 kilograms of plutonium are necessary for one nuclear weapon.

During the first few decades of the nuclear age, only a few countries possessed uranium enrichment and plutonium reprocessing technologies. During the past years however, access to this technology has increased. Today, some 440 commercial nuclear power reactors operate in 31 countries around the world. While the majority of these countries do not pose a proliferation concern, they do possess the technical capabilities to divert fissile material for the production of nuclear weapons.

The presence of large civilian and military stockpiles of fissile material is also cause for concern. As of 2003, some 3,700 metric tons of HEU and plutonium exist in 60 countries. Some of this material is not safeguarded (as in the case of Pakistan, a country that is not a member of the NPT), or only poorly guarded and subject to theft (as in the case of Russia).

The Nuclear Fuel Cycle and the nuclear Non-Proliferation Treaty (NPT): The nuclear Non-Proliferation Treaty (NPT) of 1970 is the most adhered to international arms control treaty. The NPT divides its members into nuclear-weapon states (NWS) – China, France, Russia, United Kingdom and United States – and non-nuclear weapons states (NNWS). At the heart of the treaty is a central bargain between the NWS and NNWS. Under Article IV of the NPT, the NNWS agree to forego nuclear weapons, and in exchange, are given an “inalienable right to develop research, production and use of nuclear energy for peaceful purposes without discrimination.” NNWS also have “the right to participate in the fullest possible exchange of equipment, materials and scientific and technological information for the peaceful uses of nuclear energy.” To fulfill their side of the bargain, the NWS commit under Article VI to undertake “to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a treaty on general and complete disarmament under strict and effective international control.”

It is important to note that when the NPT was first conceived in the late 1960s, it was generally assumed that not all member states should develop full fuel cycle capabilities because of the sensitive technological components involved.

The Nuclear Fuel Cycle and Nuclear Proliferation: The issue of nuclear proliferation is one of the core debates surrounding nuclear fuel cycle technologies. Now nuclear weapons states, India and Pakistan both pursued plutonium programs that they justified as a legitimate part of their civil nuclear programs. Libya and North Korea have misused Article IV and the dual-use nature of nuclear reactors and fissile materials to pursue clandestine nuclear weapons activities.

In order to respond to the proliferation of sensitive part of the nuclear fuel cycle, several preventative measures have been under the international nonproliferation regime, including: safeguards monitored by the International Atomic Energy Agency (IAEA), export control regimes, and negotiations on prohibiting the production of fissile materials world-wide.

  • Each NNWS NPT member state has to enter into a safeguards agreement with the IAEA that requires the state to declare its nuclear facilities and activities. IAEA inspectors verify these declarations through on-site inspections in the host country. The Additional Protocol allows for more intrusive inspections and obligates states to make available more information to the IAEA.

One of the limitations to these safeguards activities is that they only apply to NNWS. All five NWS own full nuclear fuel cycle and only abide by voluntary safeguards agreements. Another issue is that the Comprehensive Safeguards Agreement and Additional Protocol are far from universal. Some one fifth of NPT members have not yet brought their safeguard agreements into force, and more than 100 states have yet to accede to the Additional Protocol.

  • While export control laws are not directly stipulated by the NPT, Article III (2) of the NPT obliges states not to transfer fission materials or technologies to NNWS not covered by safeguards. Soon after the NPT came into force in 1970, two groups of states formed to voluntarily restrict the export of dual-use materials. The Zangger Committee and Nuclear Suppliers Group (NSG) both drew up guidelines on the kind of sensitive materials and technologies that can be transferred across borders.

A number of NPT states belonging to the Non-Aligned Movement (NAM) criticize export controls, citing their inalienable right to the peaceful use of nuclear energy provided for by Article IV of the NPT. They refer to the discriminatory nature of export controls and claim it harms their economic development. Moreover, not all NPT members are party to these export control regimes, which limits their effectiveness in halting proliferation.

  • Negotiations on prohibiting the production of fissile materials mandated in 1995 have so far failed to produce a fissile material cut-off treaty. In 1995, the Conference on Disarmament (CD) adopted the Shannon report which established an ad hoc Committee "to negotiate a non-discriminatory, multilateral and internationally and effectively verifiable treaty banning the production of fissile material for nuclear weapons or other nuclear explosive devices." While this mandate covers only military fissile materials, its implementation would contribute to the control of fissile materials in general.

Proposals Regarding the Control over Nuclear Fuel Cycle Technologies: Given the wide range of negative repercussions associated with Article IV, several proposals have recently been put forward to address the control of nuclear fuel cycle technologies so that they will not be misused for nuclear weapons purposes.

The United Kingdom and the United States seek to restrict the transfer of technologies to only those countries that already have a complete nuclear fuel cycle. This would limit the availability of sensitive materials and technologies to a certain number of states, mainly technologically advanced Western nations. The principal idea contained in this proposal is to stop fuel cycle proliferation to countries that might misuse these capabilities for military purposes.

As an alternative, IAEA Director General ElBaradei suggests to internationalize or multilateralize the nuclear fuel cycle. Under Dr. ElBaradei’s proposal, a group of countries would jointly control the multiple stages of the nuclear fuel cycle, which would take place at facilities in different countries and be controlled by more than one country. The uranium producer and supplier URENCO operated by Germany, the Netherlands and the UK is an example of such a joint project.

Both proposals have advantages and disadvantages, and are criticized by different states or groups of states that are party to the NPT.

Limiting the Transfer of Nuclear Fuel Cycle Technologies

In his February 2004 speech , President Bush addressed the need to “close the loophole” presented by Article IV of the NPT. He proposed the denial of enrichment and reprocessing technologies to countries that do not already possess them. He argued that “Enrichment and reprocessing are not necessary for nations seeking to harness nuclear energy for peaceful purposes.” Bush also called on the Nuclear Suppliers Group (NSG) to make supply of such technologies contingent on states’ accession of and adherence to the Additional Protocol.

This proposal requires a reinterpretation of Article IV of the NPT because it would restrict “the right to participate in, the fullest possible exchange of equipment, materials and scientific and technological information for the peaceful uses of nuclear energy.” It remains unclear how feasible a reinterpretation of this language is. At the 2005 NPT Review Conference, several states, including Argentina, Brazil, Egypt, France, Iran and NAM, voiced their opposition to such a proposal. One of the arguments made by these parties is that it would deepen the technological divide that already exists among the haves and have-nots of the NPT regime.

It is important to note that under this proposal, NPT states could still benefit from peaceful nuclear power and build domestic power reactors. Instead of allowing a state to develop its own nuclear fuel cycle, it would be guaranteed a supply of nuclear fuel, which would make domestic fuel production obsolete. Countries that currently possess full nuclear fuel cycles would be allowed to retain these capabilities.

Multilateral Control over Nuclear Fuel Cycle Technologies

The other recent proposal, presented by IAEA Director General ElBaradei, suggests a multilateral approach to controlling nuclear fuel cycle technologies. At the IAEA General Conference in September 2003, ElBaradei urged the consideration of the “merits of multinational approaches to the management and disposal of spent fuel and radioactive waste.” He argued that such an approach could strengthen the non-proliferation regime through improved technological control, nuclear fuel supply guarantees, and greater operational transparency.

Multilateral control could serve as a confidence building measure among participating states and make it harder for a state to break out of the non-proliferation regime. On the other hand, placing fuel cycles technologies under multilateral control would also mean a loss of certain domestic control and sovereignty.

In June 2004, ElBaradei appointed a group of international experts from 26 countries to examine possible multilateral approaches to the nuclear fuel cycle. The expert group submitted its report on multilateral approaches to the nuclear fuel cycle to the IAEA in February 2005. The report presents five multilateral national approaches whose gradual implementation would fulfill the “objective of increasing non-proliferation assurances associated with the civilian nuclear fuel cycle, while preserving assurances of supply and services around the world.” The five approaches are:

  • reinforcing existing commercial market mechanisms on a case-by-case basis;
  • using the IAEA as a guarantor of international fuel supply;
  • promoting voluntary conversion of existing facilities to multilateral nuclear approaches;
  • creating multinational and regional multilateral nuclear approaches for new facilities; and
  • developing new nuclear fuel cycles under multilateral control, by region or continent.

When the IAEA submitted the expert group report to the NPT Review Conference in May 2005 for consideration by NPT states, a number of states, including Australia, Canada, Ireland, the Netherlands, New Zealand, Norway, Sweden , and Russia, welcomed the report. Despite the urgency of the topic though, the Review Conference ended without progress being made in this area.

Source Documents