Nuclear power

Some power comes from tiny bits.

These bits make heat. This heat makes power.

This power can light up homes. It does not make dirty air.

This helps the Earth stay clean. It is a very big job. Many plants work to help us. It is a smart way to make power.

Nuclear power is a way to make electricity. It uses tiny parts of atoms to make heat. Most power comes from nuclear fission. This is when the center of an atom splits apart. This split lets out a lot of power.

Scientists first used this to light bulbs in 1951. The U.S. Navy also used it for ships. They used a pressurized water reactor. This is a type of reactor that uses water to move heat.

Nuclear power is a low-carbon source. This means it does not make much greenhouse gas. It helps keep the air clean. Some people worry about safety. They think about accidents like Chernobyl or Fukushima.

Today, there are 416 fission reactors in the world. The United States has the largest group of them. Many new reactors are being built in Asia. They use new designs to stay safe.

Nuclear power is a way to make electricity using nuclear reactions. Most of this power comes from a process called nuclear fission. This happens when the center of an atom splits apart. This split releases a huge amount of energy. Other ways to get power include nuclear decay and nuclear fusion. Nuclear decay is used in special tools for space probes. For example, the Voyager 2 probe uses it. Scientists have worked on fusion for a long time. They have operated fusion reactors since 1958. However, these have not yet made more power than they use.

To understand how it works, we can look at fission. When a nucleus splits, it releases neutrons. These neutrons can hit other nearby nuclei. This starts a self-sustaining chain reaction.

Most plants use uranium or plutonium for this. Many plants use a pressurized water reactor. This design is simple and compact. It is a popular choice for making electricity.

This type of reactor was even used to power submarines. The U.S. Navy used it for the Nautilus. This ship was the first nuclear-powered submarine.

People first discovered nuclear fission in 1938. This came after many years of studying radioactivity. In 1942, the first human-made reactor was built. It was called Chicago Pile-1. It was located at the University of Chicago.

Later, the first electricity was made in 1951. This happened at the EBR-I station in Idaho. In 1954, the Obninsk plant in the USSR joined the power grid. The first commercial station was Calder Hall in England. It started working in August 1956.

Nuclear power has a complex history with many changes. Global capacity grew to 100GW in the late 1970s. It reached 300GW by 1990. However, accidents caused many people to worry. The Three Mile Island accident happened in 1979. The Chernobyl disaster occurred in 1986. In 2011, the Fukushima accident happened in Japan. These events led to more rules and safety checks. Some countries even decided to stop using nuclear power. Italy was the first major economy to phase it out.

Today, nuclear power is a major part of our world. There are 416 civilian fission reactors in use. These reactors provide about 9% of global electricity.

The United States has the largest fleet of reactors. It generates almost 800TWh of electricity every year. Nuclear power is a low-carbon energy source. This means it does not emit much greenhouse gas. It helps reduce air pollution compared to coal or gas. One study says building plants can save many life years. This is because it prevents pollution from other fuels.

Nuclear power is the use of nuclear reactions to produce electricity. This energy comes from the tiny particles inside an atom. There are three main ways to get this power: nuclear fission, nuclear decay, and nuclear fusion. Most electricity today comes from nuclear fission using uranium or plutonium. This process happens in large nuclear power plants.

In nuclear fission, the center of an atom, called the nucleus, splits apart. When this happens, it releases a massive amount of energy. This split also releases tiny particles called neutrons. If these neutrons hit other nearby nuclei, they can cause them to split too. This creates a self-sustaining chain reaction.

Many plants use a design called a pressurized water reactor, or PWR. This design uses water to manage the heat and the reaction. The PWR was originally chosen for submarines because it is compact and simple.

Nuclear power comes in different types based on how the energy is released. Fission is the most common method used for civilian electricity. Nuclear decay is a different process used in niche areas. For example, some space probes like Voyager 2 use radioisotope thermoelectric generators. These use decay to provide power in space.

There is also nuclear fusion. This is when nuclei join together instead of splitting. Scientists have operated fusion reactors since 1958. However, they have not yet reached the point of generating more power than they consume.

The history of this science began with the discovery of fission in 1938. This followed decades of research into radioactivity. In 1942, the first human-made reactor, Chicago Pile-1, reached criticality. This was part of the Manhattan Project in the United States. The first time a reactor produced electricity was in 1951 at the EBR-I station in Idaho.

Later, the Obninsk plant in the USSR joined a power grid in 1954. The first commercial station was Calder Hall in England, which began in 1956.

Nuclear power grew very quickly in the late 20th century. Global capacity reached 100GW in the late 1970s and 300GW by 1990. However, major accidents changed how people viewed this technology. The Three Mile Island accident in 1979 and the Chernobyl disaster in 1986 caused great concern. The Chernobyl accident involved an RBMK reactor and is considered the worst nuclear disaster in history.

These events led to much stricter safety rules and more public opposition. In 2011, the Fukushima Daiichi accident in Japan also caused a re-examination of nuclear safety.

Despite these challenges, nuclear power remains a massive part of the world's energy. There are 416 civilian fission reactors operating globally. These provide about 9% of the world's total electricity, which is 2,602 terawatt hours in 2023. The United States has the largest fleet of reactors. It generates nearly 800TWh per year with a high capacity factor of 92%. The average global capacity factor is 89%.

Nuclear power is often discussed as a sustainable, low-carbon energy source. It emits no greenhouse gases during operation. It also has lower life-cycle carbon emissions than many renewable energy sources. One study suggests that nuclear plants can save 800,000 life years by preventing air pollution. This is because fossil fuels like coal and gas cause more deaths per unit of energy through pollution.

However, the anti-nuclear movement still focuses on the risks of radiation and the cost of building new plants.