Fueling Iran's Nuclear Power Plant

The reactor building of Iran's Bushehr Nuclear Power Plant is silhouetted in this November 2009 photo released by the semi-official Iranian Students News Agency (ISNA). (AP Photo)

The world waits and watches as Iran gears up to join the nuclear community. With Russian support, Iran plans to start fueling Bushehr, the country's first nuclear power plant, as early as Saturday.

Uranium fuel shipped by Russia will be loaded into the Bushehr reactor on Aug. 21, beginning a process that will last about a month and end with the reactor sending electricity to Iranian cities, Russian and Iranian officials said.

"From that moment, the Bushehr plant will be officially considered a nuclear energy installation," said Sergei Novikov, a spokesman for Russian nuclear agency Atomstroyexport. Here's what will happen.

NUCLEAR REACTORS

The fuel that powers reactors isn't the same as the fuel in nuclear bombs, which require enrichment to a much higher level. The uranium-235, or U235, used by nuclear plants is enriched to around 3.5%. Uranium must be enriched to more than 90% to be used in a nuclear warhead.

In a nuclear reactor, the heat from fission -- where individual atoms of U235 are split apart -- generates energy. Once fission begins, a chain reaction is started, and the heat from the reacting core is used to boil water and drive a steam turbine. The chain reaction can be slowed down and even turned off by introducing control rods, which contain materials that absorb neutrons.

On Aug. 21, Iran will transfer the first fuel into the reactor's engine room. Inspectors from the U.N. nuclear watchdog, the International Atomic Energy Agency (IAEA), will attend the launch ceremony.

"The fuel is sealed and IAEA inspectors must be present" to unseal it, said Iran's atomic energy chief, Ali Akbar Salehi.

The rest of the Russian fuel will be transferred to the core on Sept. 5, Salehi has said. It will take two more weeks for the reactor to reach 50 percent of its power-generation capacity, allowing it then to be linked to the national grid, Salehi said.

"It will take six to seven months to reach the maximum power level of the plant," he said.

Spent fuel contains plutonium, which can be used to make atomic weapons. Per the deal between the two countries, Russia will retrieve all used reactor fuel for reprocessing.

POTENTIAL POWER

The Bushehr plant will have a maximum 1,000-megawatt (MW) capacity, according to the IAEA, with a net capacity of 915 MW. This places it on the small end of the scale. For comparison, the Indian Point Energy Facility in upstate New York has a 2,000-megawatt capacity -- enough electricity to power about 2 million homes.

The smallest nuclear plant in the U.S. has a single reactor with 476 MW of generation capacity; the largest has three reactors with a total of 3,825 MW of capacity.

There are 440 nuclear power reactors in operation worldwide, with a total net installed capacity of 373.673 gigawatts (GW). Five nuclear power reactors are in long-term shutdown, while 61 are currently under construction. Haaretz reports that Iran plans to build 10 to 20 nuclear power plants and enrichment sites in the coming years with the final aim to produce enough nuclear fuel to cover its electricity needs.

Iran currently operates one uranium conversion and one enrichment site. A second enrichment plant is under construction. But the 64 tons of low-enriched uranium that Russia has supplied greatly exceeds the 5,300 pounds the Iranians have produced for themselves, according to the IAEA's estimates.

HISTORY

The Bushehr facility took 36 years to complete. It was begun by German electronics giant Siemens in 1975. Following the Islamic Revolution in 1979, Siemens and its subsidiary Kraftwerke (KWU) halted construction, and the site languished.

The Iraqis bombed Iran's two reactors six times during the 1980-88 Iran-Iraq war, severely damaging the plant and obliterating the entire core area of both reactors. Then, in 1995, Russia agreed to rebuild Bushehr for a total of $800 million.

The Bushehr nuclear facility is associated with the city of the same name, but is actually located near Halileh, about 8 miles south of the city. The site is also the location of Iran's Nuclear Energy College.

The plant is scheduled to start generating electricity sometime in September or October 2010.