On the nuclear trail: The dawn of a global renaissance in nuclear energy

There are a number of factors.

Among them are energy security and prices – Russia’s invasion of Ukraine caused prices of natural gas to spike, and pushed countries to prioritise domestic energy generation, such as by using nuclear power.

Pressure is also mounting on countries to reduce their greenhouse gas emissions, as extreme weather events due to climate change are wreaking increasing havoc across the world.

To date, 25 countries – including France, Japan and the United States – have pledged to triple global nuclear energy capacity by 2050, a movement that kicked off at the 2023 United Nations climate change conference.

Plans are afoot to restart Pennsylvania’s Three Mile Island nuclear station – the 1979 site of America’s worst nuclear accident – to power Microsoft’s data centres for artificial intelligence.

Nuclear energy now makes up about 10 per cent of electricity production globally, according to the UN nuclear watchdog, the International Atomic Energy Agency (IAEA). This proportion is set to grow.

Every year since 2021, IAEA has revised upwards its projections for global nuclear capacity. By 2050, it expects nuclear to supply up to 950 gigawatts (GW) of electricity, about 2½ times the amount generated in 2023.

Even Singapore – which in 2012 decided that atomic power was unsuitable for the small island state – is warming up to it as advanced technologies are making the controversial energy source safer.

Nuclear materials expert Michael Short of the Massachusetts Institute of Technology (MIT) told The Straits Times there are at least three reasons countries are keen to start or ramp up nuclear power production. He said: “First, (it’s) zero-carbon energy. Second, domestic energy security, and third, stable low prices.”

Earlier in 2024, ST travelled to four countries – France, Japan, Switzerland and South Korea – to learn more about their nuclear policies amid a new dawn for this energy form.

Solar power, Singapore’s most promising zero-emissions energy source for now, contributes only about 2 per cent of the country’s electricity needs.

Experts predict that by 2050, the percentage of solar energy in the Republic’s overall electricity mix is likely to be about 10 per cent.

The scarcity of land for solar panels and cloud cover limits the amount of energy the island state can squeeze from sunshine.

This is where nuclear energy, green electricity imports and emerging clean fuels like hydrogen could help renewable-scarce countries like Singapore reach net zero.

Nuclear energy requires the least amount of land per unit of electricity

The authorities here have been studying nuclear energy more deeply in recent years. But the country has not made a decision on going nuclear.

All existing nuclear plants today create energy through a process called fission. How does a nuclear reactor generate electricity?

In a fission reaction, radioactive uranium atoms are split into two, kicking off a chain reaction that releases a large amount of energy in the form of heat and radiation.

This heat is converted into a stable supply of electricity, unlike renewable sources which are dependent on weather – sunshine and wind energy weaken on cloudy and less windy days.

The Gosgen nuclear power plant in Switzerland needs to run for just 60 seconds to meet a person’s electricity needs for a year.

Unlike burning fossil fuels for electricity, nuclear plants do not emit any greenhouse gases and use fewer natural resources to produce large amounts of energy.

One thimble-sized uranium pellet produces as much energy as one tonne of coal, 564 litres of oil or 480 cubic m of natural gas, according to the US Office of Nuclear Energy.

For Singapore, big traditional reactors are not possible because they require large buffer zones for safety reasons and emergency response, which would be beyond the island state’s radius.

But small modular reactors (SMRs) are thought to be suitable for Singapore. These are compact fission reactors that can be factory-assembled and installed in dense urban areas as they have a smaller footprint.

The power capacity of one SMR, at about 300 megawatts, is about a third of that of a traditional reactor.

The Energy Market Authority told ST that Singapore is interested in exploring newer nuclear reactors that are being developed globally.

“We think some of the advanced nuclear technologies, the SMRs that are in development or (designed) in many parts of the world, can offer safety features that may make them feasible in Singapore,” EMA chief executive Puah Kok Keong told ST.

A new 30-year partnership with the US, inked in July, will unlock the Republic’s access to information and expertise about emerging technologies and nuclear safety.

Under the 123 Agreement on Nuclear Cooperation, research institutes in Singapore could work with US national laboratories and tech firms to perform safety simulations and modelling of SMRs, said EMA.

One SMR type the agency is closely monitoring is by Oregon-based NuScale. The company’s reactor design was the first to be certified by the US Nuclear Regulatory Commission in 2020.

NuScale, which was supposed to construct what could have been the US’ first commercial SMR, ended up having its project axed in late 2023 before construction could begin in 2026, due to projected rising costs.

Following that, the company said it would continue with its other domestic and international projects, such as in Romania, to bring the tech to market.

How a small modular reactor works

SMRs promise to be safer as their cylindrical set-up relies on natural processes like gravity and circulation to cool the core of the plant where the heat-producing nuclear reaction takes place.

The built-in safety features reduce the need for external power generators or intervention from workers. The Fukushima meltdown happened because a tsunami slammed into the coastal nuclear plant, knocking out the generators that were in place to prevent the reactors from overheating.

Since SMRs have heightened safety features and produce less power per unit compared with larger reactors, they are less likely to experience catastrophic damage.

According to IAEA, there are more than 80 SMR designs and concepts globally.

MIT’s Associate Professor Short suggested two locations in Singapore that could host SMRs – Jurong Island or a floating system out at sea. Both are away from residential areas.

“There are lots of industries on Jurong Island, and so there is local energy consumption,” he said.

EMA said the siting of a nuclear reactor requires an in-depth study based on the specific reactor design and its characteristics. The agency’s current focus remains on assessing the safety aspects of new energy tech.

The Republic is also keeping a close watch on another technology – nuclear fusion. This is far safer than fission, but is decades away from commercialisation.

In nuclear fusion, two forms of hydrogen collide to release massive amounts of energy – four times more than fission. This is the same process that powers the sun.

Since fusion energy is not based on a chain reaction like fission, it is impossible for a fusion plant to suffer a meltdown.

In March, Second Minister for Trade and Industry Tan See Leng told Parliament that Singapore is looking to see how it can contribute to the fusion supply chain.

Singapore companies and institutes, including ST Engineering and A*Star, have shown interest in solving some of the key challenges in the emerging nuclear fusion space.

As an advanced manufacturing hub, Singapore has expertise in materials science, artificial intelligence and robotics – areas that are relevant to the building of fusion reactors.

Experts said the earliest that fusion can come onto the grid would be in the 2040s.

If Singapore is serious about nuclear energy, it is important to get the public’s buy-in, said Prof Short, who is also an adjunct faculty member of A*Star’s Institute of Materials Research and Engineering.

“It takes a long time to get people receptive to something that, in the news, can look scary,” he added.

On top of building up a pool of nuclear energy experts at the tertiary level, the basics of nuclear energy can be taught in schools, and students can explore where natural radioactivity comes from, he suggested.

Natural radiation is all around us, from natural radioactive minerals in the soil to the cosmic rays from the sun. Even food contains minuscule traces of radiation.

“For older people, sharing sessions in communities could work. Assuage (their concerns) or address them where appropriate,” said Prof Short.

“The more you make more people part of the conversation… (the more they are likely to be) open to a balanced position, rather than feeling, ‘This is being forced down our throats’.”

No. A person living within a few kilometres of a nuclear power plant in Canada is exposed to an additional 0.001 millisieverts (mSv) of radiation a year, according to the Canadian Nuclear Safety Commission. This is less than half the amount of natural radiation a person in Singapore is exposed to over 24 hours, which is 0.0024 mSv.

In the US, it is 0.0001 mSv of additional radiation a year for someone living near a nuclear plant, says the country’s Nuclear Regulatory Commission. That is equivalent to the radiation received from eating one banana.

An airline passenger is exposed to 0.19 mSv of radiation on a long flight between Tokyo and New York. A high dose of 1,000 mSv will cause radiation poisoning – a life-threatening condition that includes vomiting, nausea and rectal bleeding.

This depends on how well the waste is treated, transported and stored. Spent uranium fuel rods will remain highly radioactive for 200,000 years, with the toxicity decaying over time.

In Switzerland, for example, intensely hot spent fuel is stored in deep pools inside the nuclear plants for about eight years.

After this period of time, the waste is transported to an interim storage facility in accident-proof casks that have passed safety tests, including a 9m drop and exposure to 800 deg C fires. Each barrel is topped off with an anti-plane crash lid.

The barrels of waste are stored in the interim facility for about 40 years, and the plan is to store them underground, 800m deep, at a site north of Zurich.

It is impossible for a reactor to explode like a nuclear weapon, says the American Nuclear Society. Weapons contain special materials in unique arrangements, and those are not found in a nuclear plant. They also cannot be made from parts of the nuclear plant. The fuel does not contain enough enriched uranium to be explosive.

Reactors are also designed with layers of safety systems and automatic shutdown capabilities.

The Fukushima plant exploded because of the build-up of hydrogen gas in the reactor buildings. That was not a detonating nuclear blast, but rather a chemical explosion.