Today there are about 440 nuclear power reactors operating in 33 countries, with a combined capacity of about 390 GW, providing roughly 10% of the world’s electricity.

At COP28, over 20 countries signed a joint declaration to triple nuclear power capacity by 2050. Globally, that would mean an addition of 740 GW of nuclear capacity to the current stock of 370 GW. ~ IEA

Europe

Europe is at the forefront of the nuclear renaissance, driven by the need for energy security after Russia’s full-scale invasion of Ukraine. Germany is one of the few exceptions, phasing out nuclear in favor of natural gas.

Sweden’s parliament approved a bill in November, however, scrapping the previous cap of 10 nuclear reactors, allowing more to be built.

Finland completed its Olkiluoto 3 reactor in 2023 — the first new nuclear plant in Europe in 15 years. The project takes nuclear from 33% to more than 40% of electricity generation.

Poland has an ambitious plan to build a nuclear fleet by 2033, including 3xAP1000 Westinghouse light-water reactors, 2xAPR1400 reactors (from Korea Hydro & Nuclear Power), and 6 sites with 4xBWRX-300 Ge-Hitachi SMR reactors.

France has 56 operable reactors, with a total capacity of 61.4 GW, meeting 62.6% of electricity needs. Another 1.6 GW EPR is under construction at Flamanville, in Normandy, and approval has been granted for construction of a further six EPR-2 units at three sites at an estimated cost of €52 billion.

France demonstrated in the 1980s that conversion from fossil fuels to nuclear power generation was achievable at scale.

The United Kingdom has 9 reactors at seven sites, generating 5.9 GW (14% of electricity demand). Eight are advanced gas-cooled reactors (AGRs), with one pressurized water reactor (PWR) at Sizewell. The AGRs are due to be retired by the end of the decade. Two EPR units (3.3 GW) are under construction at Hinkley Point and further SMRs are in the pipeline.

Westinghouse signed an agreement with Community Nuclear Power Limited (CNP) for the construction of four AP300 small modular reactors — a scaled down version of the AP1000 — in northeast England. It would be the UK’s first privately-financed SMR fleet. ~ World Nuclear News

Asia

In Asia, India has 22 reactors generating 7.2 GW (3% of electricity demand), with another 8 (6.0 GW) under construction. In April 2023 the government announced plans to increase nuclear capacity from 6.8 GW to 22.5 GW by 2031. Early reactors used were the Russian-designed VVER-1200, from Rosatom, but the latest are Indian-designed and built PHWR-700s.

Bangladesh is building two VVER-1200 reactors, with the first scheduled for completion this year, while Uzbekistan plans to complete two more VVER-1200s by 2028.

The Japanese government has adopted a plan to extend the operation of existing nuclear power reactors and replace aging facilities with new advanced ones…..Prior to the March 2011 accident at the Fukushima Daiichi plant, Japan’s 54 reactors had provided around 30% of the country’s electricity. However, within 14 months of the accident, the country’s nuclear generation had been brought to a standstill pending regulatory change. So far, ten of Japan’s 39 operable reactors have cleared inspections confirming they meet the new regulatory safety standards and have resumed operation. Another 17 reactors have applied to restart. ~ World Nuclear News

South Korea has 25 reactors generating 24.5 GW (30.4% of electricity consumption) and plans to complete another 6 reactors by 2033.

Mainland China has 54 reactors generating 52.2 GW (5% of electricity consumption). Their nuclear program is accelerating, with another 21 reactors (22.1 GW) under construction.

China: Nuclear power generation

Middle East

In the Middle East, Egypt plans four Russian VVER-1200 reactors, while Turkey has four under construction, two of which are scheduled for completion by the end of 2024.

North America

In North America, Canada has 19 reactors with 13.6 GW of capacity and  is refurbishing existing CANDU reactors at the Darlington and Bruce sites in Ontario which will extend their operational life by 30 years.

The US has 92 reactors, with a capacity of 94.7 GW, generating 18.2% of electricity. Georgia Power is completing two new Westinghouse AP1000 reactors at Vogtle — Unit 3 was commissioned in 2023 and Unit 4 is expected by June 2024 — at a total cost of $31 billion.

Weaknesses

The three primary weaknesses of nuclear energy are meltdown risk, nuclear waste and construction costs.

Meltdown

There are two nuclear energy accidents that have been rated maximum severity (7) on the International Nuclear Event Scale: Chernobyl in 1986 and Fukushima in 2011.

Explosion of the No. 4 reactor of the Chernobyl Nuclear Power Plant, near the city of Pripyat in the north of Ukraine, killed two workers and caused the hospitalization of 237 workers, 137 for acute radiation syndrome, of whom 28 later died. A design flaw in the control rods and failure to implement recommendations from the chief design engineer — after an earlier incident at another reactor — led to a power spike during a shutdown. The subsequent steam explosion destroyed the reactor casing, blasting the upper plate through the roof of the reactor building. A much larger second explosion — caused either by hydrogen from super-heated steam or a thermal explosion of the reactor due to the uncontrollable escape of fast neutrons — started graphite fires that dispersed radiation across a wide area. Dispersion of radio-nuclides in the atmosphere resulted in 4,000 cases of childhood thyroid cancer of which 15 were fatal. A 2006 study by the World Health Organization predicted an increase of 9,000 cancer-related fatalities in Ukraine, Belarus and Russia. The 30km exclusion zone established around the site has affected 107,000 residents.

The Fukushima accident resulted from hydrogen explosions in AP1000 reactors 1 to 4, caused by a tsunami that breached the sea wall and damaged the electrical grid, backup power, cooling pumps and seawater injection lines. There was one worker fatality from cancer caused by radiation, six others were treated for various cancers and 37 for physical injuries. Authorities established a 20km evacuation radius, involving 78,000 residents. Almost 1.2 million cubic meters of seawater were contaminated. The water is undergoing purification to remove radio-nuclides — except for tritium which cannot be separated. The treated water is being released into the ocean, with negligible exposure to local residents. Fishing exports were resumed in 2016.

New safety standards have been implemented in later designs, including passive safety systems that require minimal operator intervention and TRISO coated fuel pellets, used in many Gen IV reactors, that prevent the core from reaching meltdown.

TRISO fuel

Each TRISO particle is made up of a uranium, carbon and oxygen fuel kernel. The kernel is encapsulated by three layers of carbon- and ceramic-based materials that prevent the release of radioactive fission products.

The particles are incredibly small (about the size of a poppy seed) and very robust. They can be fabricated into cylindrical pellets or billiard ball-sized spheres called “pebbles” for use in either high temperature gas or molten salt-cooled reactors.

TRISO fuels are structurally more resistant to neutron irradiation, corrosion, oxidation and high temperatures (the factors that most impact fuel performance) than traditional reactor fuels. Each particle acts as its own containment system thanks to its triple-coated layers. This allows them to retain fission products under all reactor conditions.

Simply put, TRISO particles cannot melt in a commercial high-temperature reactor and can withstand extreme temperatures that are well beyond the threshold of current nuclear fuels. ~ Energy.gov

Nuclear Waste

We can find no record of injuries or environmental contamination from stored nuclear waste. Low-level waste (90% of total volume) is typically packed and sent to land-based disposal for long-term management. High-level radioactive waste (HLW) is normally stored near the surface for about fifty years — allowing decay of radioactivity and heat — to make handling safer. Storage of used fuel is normally in ponds or dry casks, either at reactor sites or centrally.

Deep Geological Disposal

Deep geological disposal is the preferred long-term solution for HLW, either in mined repositories or boreholes.

The Swedish proposed KBS-3 disposal concept uses a copper container with a steel insert to contain the spent fuel. After placement in the repository about 500 meters deep in the bedrock, the container would be surrounded by a bentonite clay buffer to provide a very high level of containment of the radioactivity in the spent fuel over a very long time period.

KBS-3 Deep Geological Disposal

Finland’s Onkalo repository is expected to start operating in 2024. It will be the first deep geological repository licensed for the disposal of used fuel from civil reactors.

The US DOE proposes to use Yucca Mountain, located in the remote Nevada desert, as the sole US national repository for spent fuel and HLW from nuclear power and military defense programs. The repository would exist 300 meters underground in an unsaturated layer of welded volcanic rock. Waste would be stored in highly corrosion-resistant double-shelled metal containers, with the outer layer made of a highly corrosion-resistant metal alloy, and a structurally strong inner layer of stainless steel. Since the geological formation is essentially dry, it would not be back-filled but left open to some air circulation. Drip shields made of corrosion-resistant titanium would cover the waste containers to divert possible future water percolation and provide protection from possible falling rock or debris. Containment relies on the extremely low water table, which lies approximately 300 meters below the repository, and the long-term durability of the engineered barriers. The Nuclear Regulatory Commission environmental impact assessment assessed that the repository design would prove safe for one million years. (World Nuclear)

Fast Breeder Reactors

A further proposal is to use HLW as fuel for a new generation of fast-breeder reactors. Breeder reactors extract almost all of the energy contained in uranium or thorium, reducing fuel needs and waste storage by a factor of close to 100 compared to light water reactors. Breeder reactors use molten salts, lead  or helium gas for cooling.

Experimental Breeder Reactor-II sodium-cooled fast reactor operated by Argonne National Laboratory in Idaho from 1965 to 1994

Construction Costs

Construction costs for large reactors have soared due to inflation, failure to meet construction targets, legislative obstacles and resistance from opposition groups. Georgia Power is one such example. Units 3 and 4 at Vogtle are expected to be completed in 2023/24 at a cost of $31 billion, compared to an initial projected cost of $14 billion and completion in 2017.

On-site construction of large Generation III reactors is a major cost factor. Project scale and time to complete make cost overruns inevitable.

Hinkley Point C: Dome Installation

Hinkley Point C in the UK is another example, with scheduled completion in 2025 now delayed to 2030 and costs projected to rise to between £31 and £34 billion (at 2015 prices). Managing director Stuart Crooks identified some of the challenges, apart from the COVID-19 pandemic which caused a 15 month delay to the project:

“Going first to restart the nuclear construction industry in Britain after a 20-year pause has been hard. Relearning nuclear skills, creating a new supply chain and training a workforce has been an immense task which others will benefit from for decades to come. Like other infrastructure projects we have found civil construction slower than we hoped and faced inflation, labor and material shortages on top of COVID and Brexit disruption.”

“The good news is that much of that pioneering work to rebuild our industry is done. Once we learn how, we see performance improve by 20-30% when we repeat work on our identical unit two.”

New Generation IV designs of small modular reactor are far smaller, enabling construction at off-site facilities with modules then transported to site. But economies of scale will only be achieved if development is focused on a few SMR models with standardized components manufactured in off-site facilities. The proliferation of competing designs is likely to be self-defeating, with ballooning costs forcing many to fall by the wayside.

Strengths

Reliability

A reliable electricity grid needs power generation sources with high availability to meet baseload power demands, 24×7. Customers such as data centers, heavy industry, critical services such as hospitals and many other businesses require uninterrupted power.

The grid also requires additional assets that can be easily switched on/off to meet peak demand. Grids that rely on a high percentage of renewables tend to be unstable, with unpredictable surges of power that are unlikely to coincide with peak demand. Wind for example, tends to peak at night, solar during the day, while demand tends to peak between 5 and 7 pm on weekdays.

Grids are also historically structured in a hub-and-spoke arrangement, with power being drawn from a centralized source. Renewables tend to be dispersed, increasing the difficulties of connecting to existing lines that already carry power from other sources.

Greenhouse Gas Emissions

A major advantage of nuclear is the extremely low levels of greenhouse gas emissions. That is why so many countries are adopting nuclear in order to meet their Net Zero targets.

Uranium

Uranium is widely available, with known resources expected to last about 90 years at current rates of usage of some 67,500 metric tons per year.