Nuclear Energy: Definition, Working, pros, and Cons

What is Nuclear Energy?

Nuclear energy comes from splitting atoms in a reactor to heat water into steam, turn a turbine and generate electricity. Ninety-three nuclear reactors in 28 states generate nearly 20 percent of the nation’s electricity, all without carbon emissions because reactors use uranium, not fossil fuels. These plants are always on: well-operated to avoid interruptions and built to withstand extreme weather, supporting the grid 24/7.

Nuclear energy is a form of energy released from the nucleus, the core of atoms, made up of protons and neutrons. This source of energy can be produced in two ways: fission – when nuclei of atoms split into several parts or fusion when nuclei fuse.

The nuclear energy harnessed around the world today to produce electricity is through nuclear fission, while the technology to generate electricity from fusion is at the R&D phase. Today, more than 400 commercial reactors operating in more than 30 countries.

Nuclear generation is the only source of electricity that can produce a constant supply of power known as baseload power reliably without emitting greenhouse gases. Nuclear energy has one of the lowest environmental impacts on land and natural resources of any electricity source.

What is the Difference Between Fission and Fusion?

All of the energy we produce comes from basic chemical and physical processes. That’s mostly been accomplished throughout history by burning carbon-based materials like wood, coal, and gas or by harnessing power from the sun, wind, and water.

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Currently, there are two ways to produce nuclear energy, through the use of fission and fusion. Fission reactions are more easily controlled than fusion reactions. This is why all nuclear power plants use fission reactions to produce energy and electricity.

Fission and fusion are two physical processes that produce massive amounts of energy from atoms. They yield millions of times more energy than other sources through nuclear reactions.

What is Fission?

Fission occurs when a neutron slams into a larger atom, forcing it to excite and spilled into two smaller atoms also known as fission products. Additional neutrons are also released that can initiate a chain reaction.

When each atom splits, a tremendous amount of energy is released.

Uranium and plutonium are most commonly used for fission reactions in nuclear power reactors because they are easy to initiate and control.

The energy released by fission in these reactors heats water into steam. The steam is used to spin a turbine to produce carbon-free electricity.

fusion vs fission

What is Fusion?

Fusion occurs when two atoms slam together to form a heavier atom, like when two hydrogen atoms fuse to form one helium atom.

This is the same process that powers the sun and creates huge amounts of energy several times greater than fission. It also doesn’t produce highly radioactive fission products.

Fusion reactions are being studied by scientists, but are difficult to sustain for long periods because of the tremendous amount of pressure and temperature needed to join the nuclei together.

How does nuclear energy work?

Nuclear energy originates from the splitting of uranium atoms a process called fission. This generates heat to produce steam, which is used by a turbine generator to generate electricity. Because nuclear power plants do not burn fuel, they do not produce greenhouse gas emissions.

A nuclear reactor produces electricity in much the same way other power plants do. The chain reaction produces energy, which turns water into steam. The pressure of the steam turns a generator, which produces electricity.

The difference is in how the heat is created. Power plants that run on fossil fuels burn coal, oil, or natural gas to generate heat. In a nuclear energy plant, heat is produced from splitting atoms a process called nuclear fission.

  • Nuclear reactor creates heat that is used to make steam
  • The steam turns a turbine connected to an electromagnet, called a generator
  • The generator produces electricity

In a Pressurized Water Reactor (PWR) the type of reactor being built in the UAE high pressure prevents water in the reactor vessel from boiling. The super-heated water is carried to a steam generator, which is made up of many small pipes.

The heat in these pipes is used to turn a second, isolated, supply of water to steam, which is in turn used to drive the turbine. The water from the reactor is pumped back into the reactor vessel and reheated. The steam from the turbine is cooled in a condenser and the resulting water is sent back to the steam generator.

nuclear energy

Advantages and Disadvantages of Nuclear energy

Nuclear Energy Pros

There are many pros and cons of nuclear energy, and it’s important to understand both sides to get an idea of what this energy resource is capable of. Knowing the pros and cons of nuclear energy will help you decide for yourself whether this energy resource is a good decision for our future energy needs and the planet.

1. Low Cost of Operation

After the initial cost of construction, nuclear energy has the advantage of being one of the most cost-effective energy solutions available. The cost to produce electricity from nuclear energy is much lower than the cost to produce energy from gas, coal, or oil unless those resources are located near the power plant they supply.

Nuclear energy also has the added benefit of facing comparatively low risks for cost inflation—unlike traditional fossil fuels that regularly fluctuate in price.

2. Reliable Source of Energy

While some energy sources are dependent upon weather conditions, like solar and wind power, nuclear energy has no such constraints. It doesn’t matter if the wind isn’t blowing or if the day is cloudy. Nuclear power plants are essentially unaffected by external climatic factors and create predictable and steady energy output.

A nuclear power plant in full-swing operation can produce energy non-stop for an entire year, which allows for a good return on investment because there is no delay in energy production.

Nuclear power plants are also reliable because we have enough uranium on the planet to generate energy for the next 70-80 years. While that may not sound like a long time, it is longer than many fossil fuels are estimated to last, and other nuclear energy sources are being explored to power nuclear power plants.

3. Stable Base Load Energy

You may not realize it, but nuclear energy is widely used in America. It makes up around 20% of all electricity generated in the United States.

This efficient energy source comes from the 98 nuclear power reactors dotted around 30 different states in the U.S. The stable production of power created by nuclear power plants means that it can ideally be used in conjunction with other forms of renewable energy.

For example, wind turbines generate significant amounts of power—when the wind blows. When the wind is blowing, nuclear plants can adjust energy output to be lower. Conversely, when the wind is not blowing and greater energy is needed, nuclear energy can be adjusted to compensate for the lack of wind (or solar) generated power.

4. Produces Low Pollution

When it comes to pollution, it’s clear that there are pros and cons of nuclear energy, and don’t worry, we’ll touch on the issue of nuclear waste in a moment. However, the overall output of pollution from a nuclear power plant is quite low compared with energy production from fossil fuels.

The current consumption of nuclear energy already reduces over 555 million metric tons of emissions every year. This reduction in greenhouse gases is a great indicator of how switching to nuclear energy can help reduce our effect on global climate change in the long run.

5. Sufficient Fuel Availability

Like fossil fuels, the uranium used to supply nuclear power plants is in limited supply. However, our uranium reserves are estimated to last another 80 years, whereas fossil fuels have a much more limited lifespan.

Since the Industrial Revolution, we have been consistently and constantly depleting our fossil fuel reserves. If we continue consuming fossil fuels and keep increasing our consumption as the world population grows, we are estimated to run out of oil by 2052, gas in 2060, and coal by 2088.

Of course, there are more fossil fuel discoveries we have yet to make, but they are fewer and farther between than ever and will eventually run out.

Switching to uranium might give us the extra time we need to find better and cleaner renewable energy resources. Plus, some countries like India, China, and Russia are already working towards using greener and more abundant thorium to power nuclear reactors.

If we switch to thorium, we will have even longer than 80 years of fuel available. However, if scientists can turn nuclear fusion into a reality, we would theoretically never run out of electricity ever again. Turning nuclear energy into sustainable energy requires the use of breeder reactors and nuclear fusion to sustain us for the foreseeable future.

6. It Has High Energy Density

On our list of the pros and cons of nuclear energy, this pro is quite astounding. Nuclear fission (the process used to generate nuclear energy) releases much greater amounts of energy than simply burning fossil fuels like gas, oil, or coal.

How much more efficient? Nuclear fission is nearly 8,000 times more efficient at producing energy than traditional fossil fuels. That’s a considerable amount of energy density. Because nuclear energy is more efficient, it requires less fuel to power the plant and therefore creates less waste as well.

Nuclear Energy Cons

On our list of pros and cons of nuclear energy, we’ve covered what makes nuclear power a great option for the future of our electricity needs. However, there are disadvantages of nuclear energy to keep in mind when considering if this power source is the best form of environmentally friendly energy for our future. Here are some of the main cons of nuclear energy.

1. Expensive to Build

Despite being relatively inexpensive to operate, nuclear power plants are incredibly expensive to build—and the cost keeps rising. From 2002 to 2008 the estimated cost to build a nuclear plant grew from $2-$4 billion to $9 billion, and power plants often surpass their cost estimates during construction.

In addition to the expense of building a power plant, nuclear plants must also allocate funds to protect the waste they produce and keep it in cooled structures with security procedures in place. All of these costs make nuclear power quite expensive.

2. Accidents

One of the first things most people think of when they hear nuclear power plant is the disaster at Chernobyl. Although we don’t know exactly how many people died as a result of the Chernobyl incident, it’s estimated that there have been as many as 10,000 deaths from the long-term effects of radiation in the region.

The Fukushima power plant crisis in 2011 showed that no matter how safe nuclear power plants are designed to be, accidents can and do happen.

3. Produces Radioactive Waste

Although nuclear energy production does not create any emissions, it does produce radioactive waste that must be securely stored so it doesn’t pollute the environment.

While radiation might sound scary, we are constantly exposed to small amounts of radioactivity from cosmic rays or radon in the air we breathe. In small quantities, radiation isn’t harmful but the radioactive waste from nuclear energy production is incredibly dangerous.

Storage of radioactive waste is a major challenge facing nuclear power plants. Because there’s no way to destroy nuclear waste, the current solution is to seal it securely in containers and store it deep underground where it can’t contaminate the environment. As technology improves, we will hopefully find better ways of storing radioactive waste in the future.

4. Impact on the Environment

Nuclear power plants have a greater impact on the environment than just the waste they produce. The mining and enrichment of uranium are not environmentally friendly processes. Open-pit mining for uranium is safe for miners but leaves behind radioactive particles, causes erosion, and even pollutes nearby sources of water.

Underground mining isn’t much better and exposes miners to high amounts of radiation while producing radioactive waste rock during extraction and processing.

5. Security Threat

Nuclear power presents a unique threat to our national security because it is powered by nuclear energy. Terrorists might target nuclear power plants to create a disaster, and the uranium used to produce the power can be turned into nuclear weapons if they end up in the wrong hands. For these reasons, security surrounding nuclear materials and nuclear power plants is extremely important.

6. Limited Fuel Supply

There might be some important pros and cons of nuclear energy, but one of the most important considerations to keep in mind is that nuclear energy is dependent on uranium and thorium to produce energy.

Unless we can find a way to create nuclear fusion or build breeder reactors before our supply dries up, we will be unable to create energy with the nuclear power plants we’ve built for the future. Ultimately, nuclear power is only a temporary solution with a very high price tag.