Wednesday, September 25, 2013

Megatons To Megawatts Program To Conclude at End of 2013

Photo of cylinder, as explained in the article text
Source: USEC Inc., with permission

In February 1993, the Russian Federation and the United States signed a 20-year, government-to-government agreement for the conversion of 500 metric tons of Russian highly enriched uranium from nuclear warheads to low-enriched uranium to fuel U.S. nuclear reactors. The agreement became known as the Megatons to Megawatts™ program. Over the life of the Megatons to Megawatts program, the low-enriched uraniam produced under the agreement provided about one-third of the enrichment services needed to fabricate fuel for U.S. nuclear reactors. The program will end in December 2013.

Uranium enrichment

Uranium is used to fuel nuclear reactors; however, uranium must be enriched before it can be used as fuel. Enriching uranium increases the amount of uranium-235 (U235) that can sustain the nuclear reaction needed to release energy and produce electricity at a nuclear power plant. Low-enriched uranium means uranium enriched below 20% U235. Normally, uranium used to fuel reactors is enriched to contain about 3% to 5% U235. Enrichment to levels of 20% or greater produces highly enriched uranium. Highly enriched uranium is used in research reactors and military applications. Highly enriched uranium may be downblended or diluted so that the amount of U235 is low enough to be suitable for commercial reactors.

Under the agreement, the United States formed the United States Enrichment Corporation (USEC), a government-owned corporation (privatized in 1998), and the Russian Federation designated Techsnabexport (Tenex) to implement the program. The terms of the agreement required that Russian highly enriched uranium be diluted or downblended to become low-enriched uranium in Russia and then shipped to the United States.

Low-enriched uranium is used to fabricate fuel for U.S. reactors. Once the United States receives the low-enriched uranium, Russia is paid for the work that was required to dilute or downblend the highly enriched uranium to low-enriched uranium, which is measured in separative work units (SWU). Russia also receives an equal amount of natural (unenriched) uranium.

The first shipment of low-enriched uranium under the Megatons to Megawatts program was made in 1995. Almost all U.S. reactors have used some fuel originating from this program. The program is 95% complete and has converted 475.2 metric tons of highly enriched uranium into 13,723 metric tons of low-enriched uranium.

In addition to the low-enriched uranium originating from the Megatons to Megawatts program, enrichment services were also provided by USEC's Gaseous Diffusion Plant, LES/URENCO's Gas Centrifuge Plant, as well as various foreign countries.

Although the Megatons to Megawatts program will expire this December, USEC Inc. signed a 10-year contract with Tenex in March 2011 to supply commercial-origin Russian low-enriched uranium to replace some of the material provided by the Megatons to Megawatts program. Deliveries under this contract begin in 2013 and are slated to continue through 2022. The contract also includes an option to double the amount of material purchased.

As under the Megatons to Megawatts program, USEC will pay Tenex the value of the work (measured in SWU) needed to create the low-enriched uranium and deliver an equal amount of natural (unenriched) uranium to Tenex. The new supply of low-enriched uranium from Tenex will gradually increase until 2015, when it reaches about half of the annual amount supplied under the Megatons to Megawatts program. The new contract will provide low-enriched uranium that can be used to fabricate fuel for U.S. reactors while USEC and others license, construct, and operate new U.S. facilities to produce U.S.-origin low-enriched uranium.  (DOE-EIA)

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