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Screen captures from embedded Kurzgesagt – In a Nutshell videos

Screen captures from embedded Kurzgesagt – In a Nutshell videos

STEM in Context

What are the Pros and Cons of Nuclear Energy?

Digital Development Team


These two “point-counterpoint” videos provide arguments for and against using nuclear energy to generate electricity.

Nuclear energy provides more than 10% of the world’s electricity. That’s almost twice the electricity generated by solar, wind and tidal energy combined. In Canada, nuclear energy provides 16% of the country’s electricity. Ontario produces nearly all of Canada’s nuclear energy.

Nuclear energy is a controversial topic. Some people think it’s too dangerous. Others think it’s a safe and clean alternative to other ways of generating electricity.

We’re going to look at some of the arguments for and against using nuclear energy. Do you know how a nuclear reactor works? If not, this would be a good time to watch this Nuclear Energy Explained video. We've also written an article on the same topic.

What are the arguments against nuclear energy?

Here are the main reasons people are against using nuclear energy to generate electricity.

3 Reasons Why Nuclear Energy Is Terrible! (2015) by Kurzgesagt – In a Nutshell (4:09 min.).

1. Nuclear Weapons 

In 1945, the bombings of Hiroshima and Nagasaki introduced the world to nuclear technology. Even since, people think of weapons of mass destruction when they hear the word “nuclear.” 

Some processes used to generate electricity using nuclear energy can also help build nuclear weapons. Thankfully, most of the world’s countries have signed the Nuclear Non-Proliferation Treaty. It allows just five countries to have nuclear weapons: China, France, Russia, the United Kingdom and the United States. Other countries can use nuclear technology to meet their energy needs. But they can’t use it to produce weapons. 

India, Israel and Pakistan have never signed the treaty. All three have nuclear weapons. In recent years, some countries that signed the treaty have threatened to build their own nuclear weapons. These countries include North Korea and Iran. North Korea, which has nuclear weapons, withdrew from the Non-Proliferation Treaty in 2002.

2. Nuclear Waste

Nuclear power plants produce radioactive waste when their fuel is produced, while they operate and when they’re taken down. Managing and getting rid of this waste is a challenge.

About 97% of the radioactive waste is fairly harmless. Most low- or intermediate-level waste loses its radioactivity after just a few days or weeks. It can then be disposed of in the same way as regular waste. 

However, the other 3% is high-level waste. It can remain radioactive for hundreds of years. High-level nuclear waste needs to be kept in a storage facility, far away from people. 

Worldwide, nuclear power plants produce about 34 000 m3 of high-level waste every year. That’s enough to fill 14 Olympic-sized swimming pools. This waste can remain very hot and radioactive for decades. Even after it cools down, it remains dangerous for thousands or even millions of years. 

Most experts agree that nuclear should be buried hundreds or thousands of metres underground. The US military operates an underground disposal site in Nevada. And Canada is developing a Deep Geological Repository for nuclear waste in Ontario. But most countries have yet to decide how they’ll dispose of their nuclear waste.

Opponents of nuclear power worry that radioactive waste stored underground could leak into groundwater. They are also not convinced that underground waste facilities will remain safe for future generations.

Deep Geologic Repository - OPG's Plan (2017) by OPG videos (1:40 min.).

3. Nuclear Accidents 

Since 1952, there have been a number of major nuclear reactor accidents. An accident in Kyshtym, Russia, caused improperly treated waste to explode. In Chernobyl, Ukraine, improperly trained staff caused an explosion. In Fukushima, Japan, there was an explosion after an earthquake and tsunami. 

These accidents released large amounts of radioactive material into the environment. Today, no one is allowed to live in the areas surrounding the damaged reactors. Long-term exposure to low doses of radiation can be very dangerous. It increases the chance that people will eventually develop cancer.

It can be hard to measure the number of deaths and illnesses caused by a nuclear accident. For example, about 50 people died from acute radiation poisoning after the initial explosion at Chernobyl. But the United Nations estimates that the accident will eventually cause 4 000 deaths. Greenpeace puts the number closer to 90 000. The debate on the Chernobyl death toll will likely continue.

The Chernobyl reactor #4 building in 2006, including the concrete container that was built over the reactor and the maximum-security
The Chernobyl reactor #4 building in 2006, including the concrete container that was built over the reactor and the maximum-security perimeter (Carl Montgomery [CC BY 2.0] via Wikimedia Commons).

What are the arguments for nuclear energy? 

Some people argue that nuclear energy is actually the best way to generate electricity. Here are three arguments in favour of nuclear energy.

3 Reasons Why Nuclear Energy Is Awesome! (2015) by Kurzgesagt – In a Nutshell (4:20 min.).

1. Nuclear energy is actually very safe 

A 2013 study by NASA found nuclear energy to be far less dangerous than other sources of electricity. In fact, the study estimates that nuclear energy causes the fewest deaths per unit of energy produced.

Deaths per 1 000 TWh (terawatt hours) of electricity production for various energy sources
Deaths per 1 000 TWh (terawatt hours) of electricity production for various energy sources (© 2019 Let’s Talk Science).


But what about nuclear accidents like Chernobyl and Fukushima? 

Supporters of nuclear energy point out that people are more likely to remember big disasters. We hear a lot about nuclear accidents in the media. But we rarely hear about diseases caused by air pollution. Every year, millions of people die because fossil fuels are burned to produce electricity.

It is also important to remember that facilities like Chernobyl were old and poorly maintained. The Canadian Nuclear Safety Commission (CNSC) strictly regulates the country’s nuclear power plants. The CNSC works to protect the health and safety of people and the environment. It also makes sure that Canada follows the Nuclear Non-Proliferation Treaty.

2. Nuclear energy does not pollute the air

Nuclear energy can provide round-the-clock electricity generation without polluting the air. 

Currently, about two-thirds of the world’s electricity is produced by burning fossil fuels. Burning fossil fuels releases greenhouse gases into the air. Greenhouse gases include carbon dioxide (CO2) and nitrous oxides (NOx).

Like solar and wind energy, nuclear energy generates electricity without releasing greenhouse gases. Of course, greenhouse gases are released when nuclear plants are built. The same is true of solar panels and wind turbines when they’re being built or installed. But overall, greenhouse gas emissions from these facilities are far lower than power plants that burn fossil fuels. 

Life-cycle greenhouse gas emissions by electricity generation method. Emissions are measured in grams of carbon dioxide equivalent per kilowatt hour of generation
Life-cycle greenhouse gas emissions by electricity generation method. Emissions are measured in grams of carbon dioxide equivalent per kilowatt hour of generation (Let’s Talk Science using data from: Intergovernmental Panel on Climate Change. 'Special Report on Renewable Energy Sources and Climate Change Mitigation. 2011)


Nuclear waste is not released into the air. Instead, it is stored in containers under very strict safety guidelines. 

Nuclear power plants can also produce electricity 24 hours a day, seven days a week. In other words, they provide a baseload supply of electricity. Solar and wind energy can supplement baseload power. But they can’t supply electricity when it’s dark or when there’s no wind.

3. Nuclear energy is embracing the future

Existing nuclear reactors were built using technology developed before the 1980s. Back then, the atomic age was in full swing. A lot has changed since then, but scientists and engineers are working hard to update nuclear technology.

For example, nuclear reactors currently run on uranium. But they could soon switch to other types of fuel, like thorium (Th, atomic number 90). Compared to uranium, thorium is more abundant and produces less waste. The waste is also less radioactive. Besides, it’s way more difficult to turn thorium into nuclear weapons.

Did you know? 

For more than 50 years, AECL's Chalk River Laboratories have been testing thorium-based fuels. They could soon be used in Canada’s CANDU nuclear reactors.

Basically, debates on nuclear energy are about how dangerous it is. 

Some people focus on how nuclear technology can be used to create weapons. Nuclear power plants also produce harmful waste. Though rare, accidents can be devastating. 

Others see nuclear energy as a lot less dangerous than the alternatives. And in the future, it could make generating electricity even safer. 

Now you’ve seen the arguments for and against nuclear energy. So what do you think? Is it worth the risk? Or should we move away from nuclear energy altogether?

Starting Points

Connecting and Relating

What do you think of when you hear the term “nuclear energy?”
Would you support the construction of a nuclear power facility in or near your community?
Do you feel safe from the threat of nuclear weapons? Why/why not?
Does any of the electricity used in your community come from a nuclear power plant?

Relating Science and Technology to Society and the Environment
  • How have nuclear accidents and the development of nuclear weapons influenced how people and governments think about nuclear energy? Explain.
  • Do you agree with the statement posed in the video against nuclear energy that “The road to deadly nuclear weapons is always paved with peaceful reactors”? Explain.
  • Supporters of nuclear energy state that it is a very safe source of energy when properly regulated. What level of risk, if any, should we consider acceptable with this technology? Explain.
  • Does the fact that the generation of electricity from nuclear power plants does not emit carbon dioxide or other greenhouse gases mean that it can be considered a source of “green energy”? Explain.
Exploring Concepts
  • What were the short-term and long-term impacts of the nuclear accidents at Chernobyl and Fukushima?
  • What are the issues involved with the long-term storage of nuclear waste?
  • Where does nuclear waste get stored in Canada?
  • Compare and contrast the emissions from a nuclear power plant to those from a coal-based power plant.
  • What are some of the advantages of thorium reactors over traditional nuclear reactors?
Nature of Science/Nature of Technology
  • Should more funding be provided to seek scientific solutions to nuclear waste problems? Why/why not?
  • What role, if any, should scientists play in helping the public make a reasoned decision for supporting or opposing the development of nuclear energy? Explain.
Media Literacy
  • Does the way nuclear energy is portrayed in the media generate fear or acceptance of this technology? Explain.
  • What role does nuclear energy and nuclear weapons play in pop culture? Explain.
  • Is the issue of climate change affecting how people or the media perceive nuclear energy? What evidence can you find in the media? 
  • Are the positive and negative aspects of nuclear energy given equal treatment by media sources? Why/why not?
Teaching Suggestions
  • This article with embedded videos can be used to support teaching and learning of Physics, Environmental Science, Technology & Engineering, Pollution, Climate Change and Nuclear Energy related to nuclear, radiation, fission & fusion, electricity generation, energy impacts and climate change. Concepts introduced include nuclear weapons, radioactivity, greenhouse gases, thorium and uranium.
  • After reading this article and watching the videos, teachers could have students conduct a My Questions Round Robin learning strategy to practice their questioning skills and ask personally relevant questions of the content. Download ready-to-use reproducibles using the My Questions Round Robin learning strategy for this article in [Google doc] and [.pdf].
  • To consolidate learning from the content, teachers could have students discuss the positive and negative aspects of building a nuclear power plant using a Pros & Cons Organizer. Download ready-to-use reproducibles using the Pros and Cons Organizer learning strategy for this article in [Google doc] and [.pdf]
  • Teachers could also have students consider the concerns of using nuclear power from different perspectives, using an Issues & Stakeholders learning strategy. Download ready-to-use Issues and Stakeholders reproducibles using the learning strategy for this article in [Google doc] and [.pdf]. Download the Issues and Stakeholder sample student response [.pdf]
  • To conclude the lesson and have students reflect on learning, teachers could provide students with an Exit Slip to complete. Download ready-to-use reproducibles using the Exit Slip learning strategy for this article in [Google doc] and [.pdf]

Learn more

Nuclear Power in the World Today (2019) World Nuclear Association -- Fact sheet about the use of nuclear power around the world. Includes stats, graphs, images, and lists. Note that this article was also used as a reference.

The Chernobyl Gallery (2016) -- An image gallery of the Chernobyl nuclear disaster site 33 years after the accident occurred

The Safest Source of Energy will Surprise You (2018) Jeff Desjardins, Visual Capitalist -- Article containing information and an infographic about the relative safety of the different forms of energy generation. Note that this article was also used as a reference.


Anti-Defamation League. (n.d.). The Iranian Nuclear Threat: Why it Matters. Retrieved from

Canadian Nuclear Safety Commission. (2017, December 8). What is Radioactive Waste? Retrieved from

Greenpeace. (n.d.). Nuclear waste. Retrieved from

Harrabin, R. (2014, September 12). Friends of the Earth's shift on nuclear should be celebrated, not denied. Retrieved from

Mycio, M. (2013, April 26). How Many People Have Really Been Killed by Chernobyl? Retrieved from