The Director General of the International Atomic Energy Agency (IAEA), Rafael Mariano Grossi, has referred to the perilous situation around Ukraine's Zaporizhzhia nuclear power plant—caught up in a war zone—as "playing with fire." The IAEA report just released that covers the visit, calls for "a nuclear safety and security protection zone" around the plant and that “shelling on site and in its vicinity should be stopped immediately."
The situation at Zaporizhzhia is genuine cause for alarm. The six 1,000 megawatt reactors that make up the Zaporizhzhia nuclear power plant, along with their irradiated fuel pools and nuclear waste storage casks, comprise pre-deployed weapons of mass destruction that, under a worst case scenario, if missiles strike and breach one or more of the units, would result in the spread of radioactive contamination across potentially thousands of miles.
What would need to happen? Under a military attack on a reactor, critical safety-related systems, structures and components can be damaged and destroyed. Primary and backup electrical power can be lost, essential for the operation of reactor cooling systems. This would result in the overheating of nuclear fuel and an ensuing core meltdown.
A core melt can not only burn through steel and concrete but will generate explosive hydrogen gas, resulting in a breach of containment and a release of radioactivity to the environment.
The fuel storage pools present an even greater potential for catastrophe. Fire and explosions could cause the pools to drain down or boil dry, exposing hundreds of tons of highly radioactive "spent" fuel rods and leading to fires and explosions that would release even larger amounts of radioactivity downwind and downstream.
Even if only one reactor was struck, the conflagration could spread to the others, as we saw at the 2011 Fukushima nuclear disaster in Japan, magnifying the scale of the catastrophe.
The radioactive fallout released by such fires and explosions would persist in the environment for decades or longer, as has happened around the Chernobyl nuclear site in northern Ukraine, which even today, 36 years after that single reactor disaster, sits within a 1,000 square mile radioactively contaminated exclusion zone.
What are the odds of this happening at Zaporizhzhia? Assessments vary. Some experts allege that the reactor containment buildings are robust enough to withstand shelling or even bunker-busting missile strikes.
But the fuel pools, with even larger inventories of both thermally and radioactively hot waste, are not housed within the protective containment buildings.
Nor are the closely congregated dry casks that hold the still extremely hot nuclear waste already offloaded from the fuel pools. The building housing these latter was apparently already struck, according to the IAEA report.
But even without a direct hit from an attack on the Zaporizhzhia site, the weakest link in this inherently dangerous technology is the potential for failure of the offsite electrical grid, followed by the failure of on-site backup power— usually supplied by diesel generators that sometimes don't work and can't run indefinitely.
These factors alone could lead to loss of control of one or more of the reactors and a catastrophic meltdown.
However, it doesn't really matter if the odds of this happening are 99% or 1%, as the consequences of a disaster would be the same. It's simply too big of a gamble. That's why the disconnect between Grossi's dire warnings, and his agency's continued promotion of nuclear power is so strikingly disingenuous.
Nuclear power is also a liability beyond the war zone. Study after study has shown that it is too slow and too uneconomic to contribute to climate mitigation and in fact gets in the way of needed action to minimize the worst effects.
The argument to keep reactors operating is contradicted by the reality that currently operating reactors now cost more to run than providing the same services by building and operating new renewables, or by using electricity more efficiently. Renewable energy can also reduce the same amount of carbon emissions faster and more cheaply than nuclear power.
In addition, focusing time and money on the continued use of nuclear power, and especially on funding new construction, demonstrably hinders the development of renewable energy. Countries that have focused on nuclear power (such as France, which in late August saw 57% of its nuclear generation capacity offline while also suffering energy shortages and soaring costs) have squeezed out renewables that are now not there to fill the gap.
The "new" reactors that stand in the way of climate progress fall broadly under a category called Small Modular Reactors (SMRs), which are in fact not a new design and do not resolve many, if any, of the current problems with nuclear technology.
As physicist Dr. Edwin Lyman of the Union of Concerned Scientists points out in his paper, Advanced Isn't Always Better, none of the non-light-water reactors under consideration are genuinely new or improved. All present unique, numerous and increased safety problems that deliver no significant advantages over traditional light-water reactors to justify their development, given their considerable costs and risks.
A serious nuclear accident is expensive and dwarfs the already exorbitant routine costs of nuclear energy. Even conservative calculations for the price of cleanup, health care, resettlement, research, radiation monitoring and remediation resulting from the 1986 Chernobyl nuclear disaster are in the hundreds of billions of dollars.
The costs of the Fukushima disaster are currently estimated at close to $200 billion, but those numbers will continue to climb as expensive radioactive waste remediation and social and health costs mount.
Choosing renewables over nuclear, then, is a no-brainer even on a good day. But the drama and danger around the war-torn reactors in Ukraine should sound the death knell for nuclear power once and for all. The outcome at Zaporizhzhia now rests on rational human behavior and luck. Neither of these has proven to be a sound basis for survival.