How the Zaporizhia Nuclear Power Plant Differs from Chernobyl (And What Are the Risks of a Conflict Between Ukraine and Russia)

“A missile in the wrong place at the wrong time can have far-reaching consequences,” warned a former UN nuclear watchdog official.

However, he clarified that a projectile is unlikely to cause damage to the reactor, which is protected by concrete and metal meters.

The danger is that the power to the bomber’s cooling system will be cut off, meaning the reactor or spent fuel will become too hot. Causes the fuel to melt and emits radiation.

Additionally, if employees are capable of performing, they may “make mistakes” due to the pressure they are under. “It’s a dangerous game that has to stop,” Heinonen added.

“The news from our team is very worrying,” said Raffaele Croci, head of the IAEA, whose staff said there had been damage to some buildings, systems and equipment at the plant.

“There have been explosions at the site of this huge nuclear power plant, which is totally unacceptable. Whoever is behind it, Stop immediately. As I have said many times, they are playing with fire.

But, what does the plant look like and what are the risks?

The Zaporizhia Nuclear Power Plant, built between 1984 and 1995, is the largest nuclear power plant in Europe and the ninth largest nuclear power plant in the world.

It has 6 reactors of 950 MW each and a total generation of 5,700 MW, energy Enough for about 4 million homes.

According to the IAEA, in normal times the plant produces 20% of Ukraine’s electricity and nearly half of the electricity produced by the country’s nuclear power plants.

The plant is located in the southeast of Ukraine, in Enerhodar, on the banks of the Khakovka Reservoir, on the Dnieper River. It is about 200 km from the disputed Donbas region and 550 km southeast of Kiev.

The importance of the center led to Russia To be captured in March, at the beginning of the war. Since then, both sides have repeatedly accused each other of bombarding each other. Moscow retained Ukrainian technicians to operate the facility.

In August, the plant was temporarily disconnected from the Ukrainian power grid for the first time in its history, after fires twice brought down its last remaining 750-kilovolt power line.

Nuclear experts at the UN They conducted their first inspection at the plant in SeptemberTogether with the Russian soldiers, he discovered that the integrity of the plant had been “violated several times”.

Some researchers point out that Zaporizhia plant Different and saferA than ChernobylIt was the site of the world’s worst nuclear disaster in 1986.

The six reactors at Zaporizhia, unlike Chernobyl, are pressurized water reactors (PWRs) and have containment structures around them to prevent any release of radiation.

“Saphoricia was built in the 1980s, so it’s relatively modern,” he says. Mark Wenman, Director of the Center for Doctoral Training in Nuclear Futures. “It has a solid containment building. It is 1.75m thick, heavily reinforced concrete on a seismic bed. [para soportar los terremotos]… Y It takes a lot to break through“.

He rejects comparisons with Chernobyl in 1986 or Fukushima in 2011. Chernobyl had serious design flaws, he explains, while at Fukushima the diesel generators flooded, something he hopes won’t happen in Ukraine because the generators are inside the control building.

Zaporizhia plant It also has no graphite in its reactor. At Chernobyl, graphite caused a significant fire and was the source of a radiation plume that traveled across Europe. Additionally, PWR reactors also have built-in fire protection systems.

After 9/11, nuclear power plants were tested for possible attacks by large aircraft and found to be mostly safe, so damage to the reactor control building would not pose a huge risk.

Power outages are a major concern. For nuclear reactors. If that happens and the standby diesel generators fail, there will be a loss of coolant. Without power to the pumps around the reactor core, the fuel will begin to melt.

On August 25, the plant was temporarily disconnected from Ukrainian power after its last remaining 750-kilovolt power line caught fire twice. The other three were dismissed from service during the war.

In that case, power was supplied to a low-power line from a nearby coal-fired power station, according to officials. Diesel generators were also used.

However, the Ukrainian Nuclear Energy Agency says the generators are not a long-term solution, and that if the last power line in the national grid breaks, the nuclear fuel could start melting and “release radioactive material into the environment.” .

A pump and generator failure can cause overheating of the reactor core and destruction of plant facilities.

“It won’t be as intense as Chernobyl, but it will still cause a release of radioactivity. It depends on which way the wind is blowingsays Claire Cargill, professor of nuclear material decay at the University of Sheffield.

For her, the risk of something going wrong is real, and Russia will emerge like Central Europe.

However, Professor Istok Dselj, a professor of nuclear engineering at the University of Ljubljana in Slovenia, believes so. The risk of a major radiological incident is lowOnly two of the six reactors are operational.

“There is no reason to worry from the point of view of European citizens,” he says. As the other four reactors are in cold state, the amount of energy required to cool the reactors is low.

Another major security risk could come from spent fuel at Zaporizhia. After fueling, the waste is cooled in spent fuel ponds and then moved to dry storage.

“If they are damaged, there will be a release of radiation, But it’s nowhere near as serious as the loss of coolantProfessor Cargill says.

Iztok Tiselj hopes that any output will be small.

At the center of the crisis are the plant’s employees, who work under Russian occupation and under extreme stress. Two workers told the BBC about the daily risk of being trafficked.

United Nations Secretary-General Antonio Guterres has called on Russia to withdraw its forces and demilitarize the region with a “secure perimeter”. Russia refusedThis, he argued, would make the plant more vulnerable.

Workers have warned of disaster if Russia tries to shut down the entire plant in order to cut off power from Ukraine and reconnect it to the occupied Crimean peninsula instead.

Mark Wenman thinks so The human factor The greatest danger of a nuclear accident comes from chronic fatigue or stress: “It violates all safety principles.”

Claire Cargill says that if something goes wrong, they should be in top shape, and presumably they aren’t.

In a letter signed by dozens of staff, they call on the international community to reflect: “We can professionally control nuclear fission, but we are defenseless against the recklessness and madness of people,” he says.

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