Nuclear power is the utilisation of nuclear reactions to generate energy. Nuclear power can be generated by nuclear fission, nuclear decay, or nuclear fusion processes. Nowadays, nuclear power plants produce the great bulk of the electricity generated by nuclear fission of uranium and plutonium. Nuclear decay processes are employed in specialised applications such as radioisotope thermoelectric generators in space probes such as Voyager 2. International research is still focused on generating energy from fusion power.

A nuclear reactor, known as a power plant, is a collection of equipment that can regulate nuclear fission to generate energy. Pellets of the element uranium are used as fuel in nuclear reactors to produce nuclear fission. Uranium atoms are driven to disintegrate in a nuclear reactor. The atoms split, releasing small particles known as fission products. Fission products divide additional uranium atoms, triggering a chain reaction. Heat is produced by the energy released by this chain reaction.

Nuclear fission generates heat, which heats the reactor’s cooling agent. Water is commonly used as a cooling agent; however other nuclear reactors employ liquid metal or molten salt. Steam is produced by the cooling agent after it has been heated by nuclear fission. Steam drives turbines, which are wheels powered by a flowing stream. Turbines power generators, which are engines that generate electricity.

History of Nuclear power

The first generation of electricity from nuclear power

The United States Navy was the first to create workable nuclear power. Using the S1W reactor to move submarines and aircraft carriers. In January 1954, the USS Nautilus, the first nuclear-powered submarine, was launched. The S1W reactor used pressurised water. This design was chosen because it was simpler, more compact, and easier to operate than competing designs, making it more appropriate for use in submarines. This decision would result in the PWR being the reactor of choice for power generation, having a long-term influence on the civilian energy market.

On June 27, 1954, the Obninsk Nuclear Power Station in the Soviet Union became the world’s first nuclear power plant to generate energy for a power grid, producing around 5 megawatts of electric power. On August 27, 1956, the world’s first commercial nuclear power station, Calder Hall near Windscale, England, was connected to the national electricity grid. The facility, like many other generation I reactors, was designed to produce electricity and plutonium-239, the latter for Britain’s fledgling nuclear weapons programme.

The Chernobyl disaster and the Renaissance

Throughout the 1980s, one new nuclear reactor began operations every 17 days on average. Global installed nuclear capacity had surpassed 300 GW by the end of the decade. New capacity additions have slowed dramatically since the late 1980s, with installed nuclear capacity reaching 366 GW in 2005.

The 1986 Chernobyl tragedy in the Soviet Union, which involved an RBMK reactor, impacted nuclear power development and resulted in a greater emphasis on achieving international safety and regulatory requirements. It is regarded as the greatest nuclear catastrophe in history, both in terms of overall victims (56 direct deaths) and financial cost, with the clean-up and cost estimated at 18 billion Rbls (US$68 billion in 2019, adjusted for inflation).

The World Association of Nuclear Operators (WANO) was founded as a direct result of the 1986 Chernobyl disaster to promote safety awareness and the professional development of nuclear facility operators. The Chernobyl tragedy had a significant impact on the number of new plant builds in the years that followed. As a result of these occurrences, Italy voted against nuclear power in a referendum in 1987, becoming the first country to phase out nuclear power altogether in 1990.

In a once-through fuel cycle, most nuclear power facilities employ thermal reactors with enriched uranium. Typically, fuel is removed three years after the fraction of neutron-absorbing atoms gets so large that a chain reaction can no longer be sustained. It is then cooled in on-site spent fuel pools for several years before being moved to long-term storage.

Despite its small size, wasted fuel contains considerable levels of radioactivity. Since its radioactivity decays exponentially, it must be isolated from the biosphere for hundreds of thousands of years, while emerging technologies (such as fast reactors) have the potential to drastically reduce this. Because spent fuel contains largely fissionable material, several nations (for example, France and Russia) reprocess it by removing fissile and fertile components for use in new fuel, but this process is more expensive than creating new fuel from mined uranium.

All reactors produce some plutonium-239, which is present in spent fuel, and because Pu-239 is the ideal material for nuclear bombs, reprocessing is viewed as a threat to nuclear weapon proliferation.

Every year, a typical nuclear reactor consumes around 200 tonnes of uranium. Some uranium and plutonium can be re-enriched or recycled thanks to complex methods. This minimises the quantity of mining, extraction, and processing required.

Due to worries about carbon dioxide emissions, nuclear energy was expecting a nuclear renaissance or an increase in the construction of new reactors, in the early 2000s. Around this time, the development of newer generation III reactors, such as the EPR, began.

Fukushima

Another nuclear disaster hampered the prospects of a nuclear renaissance. The Fukushima Daiichi nuclear disaster in 2011 was caused by a huge tsunami induced by the Tōhoku earthquake, one of the strongest ever recorded. The Fukushima Daiichi Nuclear Power Station saw three core meltdowns as a result of the emergency cooling system failing owing to a shortage of energy supply. As a result, the most significant nuclear catastrophe since the Chernobyl tragedy occurred. The tragedy forced several governments to reconsider nuclear safety and nuclear energy strategy.

Germany authorised plans to shut down all of its reactors by 2022, while several other countries examined their nuclear energy projects. Following the tragedy, Japan shut down all of its nuclear power reactors, some of which were permanently, and in 2015 began a phased process of restarting the remaining 40 reactors, following safety assessments and based on new operational and public approval standards.

How control in nuclear power

Nuclear poison rods can control the amount of power generated.

Nuclear poisons are materials that absorb part of the fission products produced by nuclear fission, such as a kind of xenon. The greater the number of rods of nuclear poison present during the chain reaction, the slower and more regulated the process. The removal of the rods allows for a stronger chain reaction and the generation of more power.

Methods of dealing with nuclear waste

The steam used to power the turbines and generators is eventually recycled. It is cooled by a separate building known as a cooling tower. The steam condenses back into water and may be utilized to generate more energy. Excess steam is easily returned into the atmosphere as pure water vapor, where it causes minimal harm.

Yet, radioactive material is a result of nuclear energy. A radioactive substance is made up of unstable atomic nuclei. These nuclei lose energy and can have an impact on numerous things, including animals and the environment. Radiation may be exceedingly hazardous, producing burns and raising the risk of cancer, blood disorders, and bone degradation.

Radioactive waste is the residue of a nuclear reactor’s activity. Radioactive waste consists mostly of workers’ protective clothes, tools, and any other item that has come into touch with radioactive dust. Radioactive waste has a lengthy half-life. Clothing and equipment, for example, can be radioactive for thousands of years. The state regulates how these items are disposed of so that they do not contaminate other materials.

Spent nuclear fuel and nuclear poison rods are very radioactive. Used uranium pellets must be kept in special containers designed to resemble enormous swimming pools. Water both cools the fuel and protects the exterior from radiation. Several nuclear power stations keep spent fuel in above-ground dry storage tanks.

In the United States, nuclear waste storage sites have become highly contentious. For years, the government planned to build a massive nuclear waste plant near Yucca Mountain, Nevada, for example. The idea was opposed by environmental groups and local residents.

They were concerned about radioactive waste getting into the water supply and the Yucca Mountain ecosystem, which is around 130 kilometers (80 miles) from Las Vegas, Nevada. Although the government began examining the location in 1978, plans for a nuclear waste repository in Yucca Mountain were abandoned in 2009.

The contribution of nuclear energy to the production of electricity

Nuclear power plants are produced around 15% of the world’s electricity since 2011. While the United States has more than 100 reactors, it generates the majority of its power from fossil fuels and hydroelectric energy. Nuclear power facilities generate nearly all of the electricity in countries such as Lithuania, France, and Slovakia.

Top 10 nuclear power plants

East Asia is home to the majority of the largest nuclear power plants (NPP) in the world by capacity.

Kashiwazaki-Kariwa Nuclear Power Plant, Japan (7,965MW)

With a net capacity of 7,965MW, Tokyo Electric Power Co.’s (TEPCO) Kashiwazaki-Kariwa plant in Japan is now the biggest nuclear power station in the world.

With a total installed capacity of 8,212MW, Kashiwazaki-Kariwa is powered through seven boiling water reactors (BWR).

The gross capacities of the first five units are each 1,100 MW, while the sixth and seventh units each have a capacity of 1,356 MW.

The first unit commenced commercial operation in September 1985, and the last unit began commercial operation in July 1997.

The Fukushima nuclear tragedy, however, forced the plant to stop operating in May 2012. To comply with the updated safety requirements established by Japan’s Nuclear Regulation Authority, TEPCO has begun taking steps at the plant.

Bruce Nuclear Generating Station, Canada (6,430MW)

The nuclear plant, which has a capacity of 6,430MW, is owned by Ontario Power Generation (OPG) and managed by Bruce Power.

The plant has eight pressurized heavy water reactors (PHWR) with gross capacities ranging from 786MW to 891MW. In May 1987, the last reactor of the Canadian NPP became commercially operational.

Bruce 1 was closed for a long time in 1997 and reopened in September 2012. After a lengthy halt in 1995, Bruce 2 was also resumed in October 2012. With the end of Bruce 3’s scheduled outage in July 2019, the plant’s peak capacity was boosted by 22MW to 6,430MW.

Hanul Nuclear Power Plant, South Korea (6,189MW)

The plant is now the world’s third biggest NPP, with a gross installed capacity of 6,189MW and a net design capacity of 5,908MW.

The first phase of the Hanul NPP, consisting of six pressurized water reactor (PWR) units, was completed in 2005. As part of the second phase of plant construction, two additional reactors, Shin Hanul-1 and Shin Hanul-2, are being installed to Hanul.

After the completion of phase two, the plant’s gross capacity will grow to 8,989MW.

Hanbit Nuclear Power Plant, South Korea (5,899MW)

With an installed net capacity of 5,899MW and a gross capacity of 6,164MW, South Korea’s Hanbit Nuclear Power Station, formerly known as the Yeonggwang Nuclear Power Plant is the world’s fourth biggest nuclear power plant.

Korea Hydro & Nuclear Power (KHNP) operates the power plant, which consists of six PWR units that were commissioned in 1986, 1986, 1994, 1995, 2001, and 2002, consecutively.

In November 2012, fractures were discovered in the control rod guide tube of the plant’s 1,000MW Unit 3.

Following an eight-month rehabilitation period, the facility reopened in June 2013.

Zaporizhzhia Nuclear Power Plant, Ukraine (5,700MW)

The installed net capacity of the Zaporizhzhia Nuclear Power Plant is 5,700MW, with a gross capacity of 6,000MW. It is now Europe’s largest nuclear power station and the world’s fifth largest.

The power station is located near Enerhodar, Ukraine, and it has six operating VVER-1000 PWR units that were put online between 1984 and 1995.

Energoatom, Ukraine’s state-owned National Nuclear Energy Generating Corporation owns and operates the Zaporizhzhia nuclear power station. The plant generates more than one-fifth of the country’s total power.

Gravelines Nuclear Power Plant, France (5,460MW)

The Gravelines Nuclear Power Plant, with an installed net capacity of 5,460MW and a gross capacity of 5,706MW, is the world’s sixth biggest nuclear power station.

The power station is located in Gravelines, Northern France, and is made up of six comparable capacity PWR units that were built between 1980 and 1985.

In August 2010, the nuclear power plant, owned and operated by the French electric utility company Electricity de France (EDF), set a record by delivering 1,000 billion kilowatt-hours of electricity.

Paluel Nuclear Power Plant, France (5,200MW)

The Paluel Nuclear Power Plant, located 40 kilometres from Dieppe, France, is now the world’s seventh biggest NPP by net capacity. The facility is stretched on 160ha on the English Channel’s coastline and uses water from the Channel for cooling.

EDF owns and operates the plant, which comprises of four PWRs with a total installed capacity of 5,528MW (1,382MW each) and a net design capacity of 5,200MW (1,300MW each).

The nuclear power station’s construction began in 1977. The plant’s first two units were linked to the grid in 1984. The third and fourth units were put into service in 1985. Paluel is France’s second biggest NPP, after Gravelines.

Cattenom Nuclear Power Plant, France (5,200MW)

The Cattenom Nuclear Power Plant, with a gross capacity of 5,448MW, is located in Cattenom, France. EDF owns and operates the power plant. The plant’s net capacity is 5,200MW, which is comparable to Paluel NPP plant, the world’s seventh biggest nuclear power station.

The Cattenom Nuclear Power Plant is made up of four 1,362MW PWRs. The plant’s construction began in 1979, and commercial operations began in April 1987. In 1991, the plant’s fourth reactor was linked to the grid.

Water from the Moselle River is used at the Cattenom nuclear reactor. In 2019, three of the plant’s condensers were dismantled and retubed, resulting in the replacement of 64,200 tubes.

Yangjiang Nuclear Power Plant, China (5,000MW)

The Yangjiang nuclear power station, located in China’s Guangdong region, has a gross installed capacity of 5,430MW, which is comprised of five 1086MW PWRs.

The plant, which is owned by China Guangdong Nuclear Power Company (CGNPC) and operated by Yangjiang Nuclear Power Company, has a current net capacity of 5,000MW, making it the world’s eighth largest nuclear power plant.

The plant’s first three units were completed in 2014, 2015, and 2016, while the fourth and fifth units were linked to the grid in January 2017 and May 2018, respectively.

Shin Kori Nuclear Power Plant, South Korea (4,748MW)

Shin Kori nuclear power plant, in Ulsan, South Korea, has a net capacity of 4,748MW and a gross capacity of 4,974MW.

Shin Kori nuclear power plant is South Korea’s third largest nuclear power plant and the world’s ninth largest by net capacity.

The power plant, which is owned and operated by Korea Hydro & Nuclear Power (KHNP), is equipped with four active PWR units, including two advanced power reactor-1400s (APR-1400). Two further APR-1400 units have been built at the site since April 2017 and September 2018, respectively.

The first two units of 996MW net capacity each were commissioned between 2010 and 2012, while the third and fourth units were brought online in January 2016 and April 2019, respectively.

Hongyanhe Nuclear Power Plant, China (4,244MW)

The Hongyanhe nuclear power station, located in Donggang, Liaoning province, near the seaside city of Dalian, consists of four active PWR units with a total installed capacity of 4,476MW (1,119MW each) and a net design capacity of 4,244MW (1,061MW each).

Hongyanhe is now China’s second largest nuclear power plant and the world’s tenth largest. Two further 1,000MW PWR units are now being built on the site.

Advantage of Nuclear Energy

Nuclear energy is pure, producing no pollutants and emitting no greenhouse gases.
From the standpoint of public health, nuclear energy has a significant benefit over fossil fuels.

In 2018, fossil fuels killed 8.7 million people worldwide. In contrast, only three mishaps have sparked public concern in the almost 70 years since nuclear power was introduced: the 1979 Three Mile Island accident, the 1986 Chernobyl tragedy, and the 2011 Fukushima nuclear disaster.

According to the US Office of Nuclear Energy, nuclear power has by far the highest capacity factor, with plants requiring less maintenance, operating for up to two years before refuelling, and producing maximum power more than 93% of the time throughout the year, making them three times more reliable than wind and solar plants.

Disadvantage of Nuclear Energy

The spread of nuclear weapons Some consider nuclear energy as inextricably linked to nuclear weapons technology, and fear that as nuclear technologies become more widely available, the chance of their slipping into the wrong hands increases.
Radioactive nuclear waste comprises very toxic substances such as plutonium and uranium pellets used as fuel. Because these compounds may be exceedingly harmful for tens of thousands of years, they must be painstakingly and completely removed.
As compared to other energy sources, nuclear power is one of the most expensive and time-consuming. Nuclear reactors cost billions of dollars to develop and take significantly longer than any other renewable energy infrastructure, often more than a decade.

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