[Big read] Nuclear power plants: Energy security or wartime nuclear risk? 

(Edited and refined by Candice Chan, with the assistance of AI translation.)

On 26 April 1986, the Chernobyl nuclear power plant in northern Ukraine ran a test on Reactor No. 4 as part of a scheduled shutdown.

Just seven seconds later, the reactor exploded. The force of the blast blew off the reactor’s 1,000-ton steel lid — the combined weight of three Boeing 747 aircraft — and released nearly 520 types of hazardous radioactive nuclides into the atmosphere.

The Chernobyl disaster released over 400 times more radiation than the atomic bomb dropped on Hiroshima during World War II, contaminating much of the Soviet Union.

According to official reports, nearly 8.4 million people in Belarus, Russia and Ukraine were affected by the radiation, with contamination over an area of some 155,000 square kilometres — over 210 times the size of Singapore.

Internationally cited official figures state that the Chernobyl disaster directly caused 31 deaths. As for fatalities resulting from long-term radiation exposure, estimates range from several thousand to tens of thousands, with the exact number still disputed.

Nearly 404,000 people were resettled, while several million others continue to live in areas where residual radiation may pose adverse health effects.

After the accident, the reactor was hastily sealed with a reinforced concrete “sarcophagus” to prevent further radiation leaks, but within a few years it was deemed at risk of collapse.

A larger protective structure — the New Safe Confinement — was launched in 2010 and completed in 2016. Designed to last around 100 years, it allows for the safe dismantling of the reactor using remote equipment under protective cover.

Alvin Chew, a senior fellow at the S. Rajaratnam School of International Studies (RSIS) at Nanyang Technological University (NTU), told Lianhe Zaobao that after the Chernobyl incident, there were several revisions made in the nuclear industry, including a fundamental shift in the design of the reactor itself.

“These two conventions had strengthened the protocols and guidelines of emergency preparedness in the event of a nuclear crisis,” Chew said.

However, these improvements were primarily designed for accident scenarios during peacetime, and did not address nuclear risks in wartime.

“These two conventions had strengthened the protocols and guidelines of emergency preparedness in the event of a nuclear crisis,” Chew said.

However, these improvements were primarily designed for accident scenarios during peacetime, and did not address nuclear risks in wartime.

He noted that conventional reactors in operation nowadays are mostly designed to have ‘negative void coefficient’, meaning that as temperature rises, the increase in power is moderated.

“This is an inherent safety feature in the design of a reactor which will provide more stability in the operation of the nuclear reactor.”

Next, it is a requirement for all reactors to have a containment building as the last line of defence, so that if the reactor vessel has been compromised, the radioactive materials will still be contained within the building and not be released into the atmosphere.

Following the Chernobyl accident, crisis communication was not transparent as neighbouring states which were affected had not been notified of the accident, and as such assistance could not be rendered by the international community.

To avoid a repeat, the International Atomic Energy Agency (IAEA) promoted two key conventions: the Convention on Early Notification of a Nuclear Accident and the Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency.

“These two conventions had strengthened the protocols and guidelines of emergency preparedness in the event of a nuclear crisis,” Chew said.

However, these improvements were primarily designed for accident scenarios during peacetime, and did not address nuclear risks in wartime.

On 14 April, less than two weeks before the 40th anniversary of the Chernobyl disaster, Greenpeace released a sharply worded report warning that drone strikes launched by Russia in the Russia-Ukraine conflict are putting the containment system of Reactor No. 4 at risk of failure.

Edwin S. Lyman, director of Nuclear Power Safety at the Union of Concerned Scientists, told Lianhe Zaobao that the Chernobyl disaster was not just due to a defective reactor design. It also exposed a host of systemic problems such as a lack of independent regulatory oversight, poor plant management, a culture that prioritised production over safety, a failure to develop effective emergency protocols to cope with severe accidents, and excessive secrecy.

“Unfortunately, awareness of these factors did not have a significant influence over nuclear safety culture worldwide because other countries generally put all the blame on the Soviet Union and believed, erroneously, that they were immune to such problems.”

He cited the 2011 meltdown of three reactors at Japan’s Fukushima Daiichi nuclear power plant as a consequence of such complacency.

“And today, the failure to learn the lessons of Chernobyl is reflected in the reckless push to weaken nuclear power safety standards and regulatory oversight in the United States and elsewhere to reduce operating costs and facilitate new reactor construction.”

The risks of warfare affecting nuclear power plants are not limited to Ukraine. Areas around Iran’s Bushehr nuclear power plant have also been attacked multiple times following the conflict involving the US, Israel and Iran.

Chew noted that current strikes by the US and Israel are focused on Iran’s nuclear research centres and uranium enrichment facilities, rather than directly targeting Bushehr. “Taking out the nuclear power plant will have grave consequences as the radioactive release could be more serious than the Chernobyl incident.” 

The Protocols Additional to the Geneva Conventions states that nuclear facilities come under special protection during armed conflict, and are not to be attacked or used to shield military operations. Under certain conditions, attacking nuclear facilities could constitute a war crime and a crime against humanity.

However, enforcement of these rules is almost entirely dependent on the self-restraint of the parties involved, with no effective binding mechanism. While the IAEA can deploy expert teams to monitor radiation and coordinate technical support, it cannot prevent shells and drones from striking nuclear facilities on the battlefield.

Stephen Thomas, Emeritus Professor of Energy Policy at the University of Greenwich, told Lianhe Zaobao that another concern is the siting of new plants. “If we look at the reactors ordered this century, a much higher proportion than in the past are sited in regions which appear potential conflict zones, such as Iran, Egypt, Russia, Turkey and Bangladesh and perhaps China.”

“Given that the life cycle of a nuclear power plant might be more than 150 years (20 years from project announcement to first power, 80 years of operation and 50 years to decommission), there are not many sites that it is inconceivable they will be potential conflict zones in that time period.”

How can nuclear power plants be prevented from becoming high-risk targets in war? Chew said all nuclear power plants have a containment building as a last line of defence.

“In the US, its containment building is designed to withstand the crash of an aircraft. However, no containment can withstand a direct hit from a missile. The best protection of the nuclear power plant is to site it underground, which offers maximum protection against military attacks as well as natural hazards like earthquakes.”

Lyman argued that hardening nuclear plants to withstand such attacks would be extremely costly. “The only viable pathway to address this danger is for the international community to unite and pledge that nuclear facilities and their supporting infrastructure will remain off-limits to military attack under any circumstances.”

While nuclear power plants have been exposed to unprecedented safety risks in conflicts such as those in Ukraine and the Middle East, the resulting energy crises are also forcing countries to accelerate energy transitions and reassess nuclear power as an option, after being sidelined.

European Commission President Ursula von der Leyen recently said that “it was a strategic mistake for Europe to turn its back on a reliable, affordable source of low-emissions power”.

She announced that the EU will create a €200 million (US$2.33 million) guarantee to support private investment in innovative nuclear technologies, particularly small modular reactors (SMRs), with the aim of making it operational in Europe by the early 2030s.

Japan, which saw the Fukushima disaster in 2011, also set a target in its seventh Strategic Energy Plan, approved in February 2025, to have about 20% nuclear power by 2040.

However, this target remains far from reality. Before Fukushima, Japan’s 54 reactors provided about 30% of its electricity. Today, only 15 units have resumed operation, with just 8.3% of electricity generated through nuclear power, reflecting persistent public concern over nuclear risks.

China’s accelerated expansion stands in stark contrast with Japan. Supported by state financing and domestic supply chains, China is expanding its nuclear capacity at up to ten new units per year, with construction costs as low as one-fifth of those in Europe and the US.

Official data show that China currently has 62 reactors in operation, 39 under construction, and 11 approved, with a total installed capacity of about 125 gigawatts — more than half of the world’s reactors under construction. At this rate, China is likely to overtake the US by the early 2030s to become the world’s largest producer of nuclear power.

Meanwhile, the growth of data centres and artificial intelligence is driving up electricity demand, intensifying regional energy pressures. The International Energy Agency projects that Southeast Asia will account for a quarter of global energy demand growth by 2035, largely driven by more than 2,000 data centres across Indonesia, Malaysia, Singapore, Thailand, Vietnam and the Philippines.

These countries are now actively considering and promoting nuclear options. Singapore signed a cooperation framework with Japan in March this year to strengthen collaboration in civilian nuclear energy and other low-carbon energy fields.

Vietnam plans to build two nuclear power plants with Russian support, while Indonesia aims to construct two small modular reactors by 2034. Thailand has set a target to add 600 megawatts of nuclear capacity by 2037, and the Philippines has outlined a nuclear roadmap for 2032, preparing to revive projects shelved for decades.

It remains debatable whether this “nuclear revival” is rooted in reality. Chew believes that countries are considering switching to nuclear power due to energy security, as it is the only source that can replace fossil fuels.

However, Lyman disagrees. “The current enthusiasm for nuclear development is largely based on unrealistic expectations for how quickly and cheaply new nuclear power can be brought into service and is driven more by reactor developers and advocates rather than consumers. The fact remains that new nuclear power is one of the most expensive forms of energy.”

Thomas shares a similar view. He noted that forecasts of costs and time and reactor performance by the nuclear industry have repeatedly proved hopelessly over-optimistic. “But the reality is that a high proportion of projects that are announced are not built and those that are built might take 20 or more years from project announcement to first power, and relying on nuclear power to deliver objectives on climate change and strategic electricity security seems reckless.”

Safety remains another major point of contention. Chew noted that from an engineering perspective, safety is inherent in reactor design. “Over the decades of nuclear power operation, there were only two major incidents — Chernobyl and Fukushima — but each time an incident occurs, we can only learn from the experience in how to improve the safety design and operation of a nuclear power plant.”

“Ultimately, it is down to the risk appetite of the society in accepting the technology, and for that, public education is crucial in clarifying the myths and the fear associated with nuclear power,” Chew said.

“Nuclear energy is the cleanest and densest form of energy available today to meet our future vision of net-zero carbon emissions as well as energy independence.”

However, Lyman argued: “Nuclear energy will never be completely safe because nuclear plants will always be vulnerable to extreme events that could subject them to stresses beyond those they were designed to withstand — from severe earthquakes or floods to terrorist attacks.”

He added: “So-called ‘advanced’ nuclear technologies, such as those that use passive safety systems, may provide some benefits, but they bring new risks as well. Some of those designs, such as liquid-metal-cooled fast neutron reactors or high-temperature gas-cooled reactors, even share some of the design flaws of the Chernobyl Unit 4 reactor. And ‘small’ modular reactors may pose unacceptable risks if they are deployed near densely populated areas.”

The challenges of nuclear waste and proliferation are even more difficult. Thomas said the most dangerous material must be kept isolated and safe for several hundred thousand years, but no facility exists for such material yet.

At present, only Finland has constructed a permanent deep geological repository in granite bedrock. “Whether these facilities will be safe is something we will never know,” Thomas said.

By contrast, some experts see renewable energy as a more viable path forward. Lyman believes that wind and solar power plus battery storage have the potential to provide a growing share of the world’s electricity needs with fewer risks.

Thomas added that, besides renewables, the biggest and most secure option is energy efficiency measures.

“These not only reduce emissions quickly and reliably, they also reduce the problem of energy poverty. But governments seem reluctant to commit the resources needed to this.”

Forty years after the Chernobyl disaster, nuclear energy once again stands at a crossroads. In an era shaped by climate crisis and geopolitical conflict, whether it will prove to be an indispensable zero-carbon pillar or an unmanageable high-risk gamble remains an open question.

This article was first published in Lianhe Zaobao as “核电站沦为战场新标的 核能复兴前路危机四伏”.

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