Nuclear power is a clean energy source that is important in reducing global greenhouse gas (GHG) emissions and mitigating climate change. Over the years, it has come to make up an ever-growing part of our energy mix despite facing negative public opinions over its safety. So, we had to ask: How safe is nuclear power really?

Overall, nuclear power is considered to be safe. Holistically and throughout its life cycle, nuclear power is safe and beneficial for human and animal health, the environment, and the energy grid. It is significantly safer than fossil fuels and some other types of renewable energy.

Keep reading to find out how safe nuclear power is overall, holistically, and in terms of its life cycle. Then, we’ll describe nuclear power’s pros and cons, look at how effective and efficient it is, and determine how it can help mitigate climate change.

The Big Picture of the Safety of Nuclear Power

In general, nuclear power is generated when neutrons either divide or fuse, which releases heat, produces steam, spins a turbine, and drives generators to produce electricity. 

The two ways we can generate nuclear power are via nuclear fission (when neutrons divide) or nuclear fusion (when neutrons fuse).

How Is Nuclear Power Defined

Nuclear fission is the generation of energy produced when splitting apart the nucleus of an atom. 

“Nuclear fission: a nuclear reaction in which a heavy nucleus splits spontaneously or on impact with another particle, with the release of energy.”

Cambridge Dictionary

Nuclear fusion is the generation of energy produced when lighter atoms are combined or fused to create larger and heavier atoms.

“Nuclear fusion: the process of joining two nuclei to produce energy.”

Cambridge Dictionary

All operating nuclear power plants today utilize the process of nuclear fission, whereas nuclear fusion is still very much in the research and development phase and does not currently supply energy to our power grid.

But nuclear power faces an uncertain future. Although it can produce relatively emissions-free energy, it can also face heavy criticism over safety concerns.

“Safety: the condition of being protected from or unlikely to cause danger, risk, or injury”

Oxford Dictionary

Here’s How Safe Nuclear Power Is Holistically and Across Its Life-Cycle

One way to combat the current global climate crisis threatening Earth’s environmental, economic, and social health is to transition away from traditional fossil fuels and toward clean energy sources, such as nuclear power.

Just as with any energy source, it is important to understand how safe nuclear power is before we implement it on a commercial scale. This involves analyzing all aspects of nuclear power. 

For this reason, we have split our analysis into the following categories:

• Overall safety
• Holistic safety
• Life-cycle safety
• Comparative safety

How Safe Is Nuclear Power Overall

Overall, nuclear power is considered minimally dangerous in terms of human and animal health, the environment, the energy grid, and through all stages of its life cycle. The most common risks include ionizing radiation, nuclear waste, and nuclear accidents, although these are few and very far between.

How Safe Is Nuclear Power at a Holistic Level

Nuclear power faces an uncertain future. Although it can produce relatively emissions-free energy and adjust its energy output to compensate for shifts in renewable energy output, it also faces negative public opinion due to the threat of nuclear waste. Because nuclear power comes with safety concerns, it is important to understand how safe it is at a holistic level. 

“Holistic: relating to the whole of something or to the total system instead of just to its parts”

Cambridge Dictionary

To understand how safe nuclear power is holistically, we must take into account how it affects us, the environment, and our technology. 

How Safe Is Nuclear Power When It Comes to Human and Animal Health

Overall, nuclear power is considered safe when it comes to human and animal health due to the rarity of nuclear accidents and substantial precautionary measures in place. 

One of the main concerns associated with nuclear power involves ionizing radiation, a form of energy that removes electrons from surrounding materials, damaging DNA in the process.

• Nuclear fission uses the energy released by decaying radioactive isotopes to generate electricity. If the nuclear fuel and surrounding containment structures become compromised, radioactive elements and ionizing radiation can be released into the environment and negatively impact humans and animals. 
• Nuclear fusion generates ionizing radiation via the release of neutrons during the fusion reaction. These neutrons are dangerous if humans come into contact with them, but turning off the powerplant causes the production of neutrons to cease within milliseconds. 

Ionizing radiation causes radiation sickness and death at high doses and cardiovascular disease, cataracts, sterility, and cancer at low doses. 

Another concern associated with nuclear power involves nuclear disasters, whereby the uncontrolled release of radioactive materials can cause off-site nuclear waste contamination and radiation exposure.

• Nuclear fission disasters are extremely rare, with there being only 2 major nuclear accidents (Chernobyl & Fukushima) in the roughly 70-year history of nuclear fission. Nevertheless, experts state that the air and food and water supplies within a 50-mile radius may be contaminated in the event of a disaster. 
• Nuclear fusion cannot cause a nuclear disaster because fusion reactions are not based on chain reactions. If there ever is a loss of pressure or temperature inside the reactor, the plasma cools and the fusion reactor shuts down, preventing a chain reaction from occurring.

There are also numerous safety measures in place to protect and increase the safety of nuclear fission power plant workers, including:

• Remote control of operations taking place inside nuclear reactor cores, areas with the highest levels of radiation
• Physical shielding mechanisms 
• Time limits for workers exposed to areas with high levels of radiation
• Continuous monitoring of radiation levels in all areas of a nuclear power plant
• Robust monitoring equipment and regular testing to detect mechanical failures

In short, the main risks to human and animal health include ionizing radiation and nuclear disasters. Proper safety measures, siting of nuclear power plants, and disaster preparedness plans can mitigate these risks, which are rare occurrences in the overall history of nuclear power.

How Safe Is Nuclear Power When It Comes to the Environment

Nuclear power emits minimal greenhouse gas emissions and has a minimal effect on the environment, provided that proper siting of nuclear facilities and disposal of nuclear waste occurs.

Nuclear power produces little to no greenhouse gas emissions and toxic byproducts, making it one of our most environmentally friendly sources of energy.

• Nuclear fission emits 12 grams of CO₂ equivalent per kilowatt-hour (kWh) of electricity produced, which is tied for the third-lowest out of all energy types.
• One study on nuclear fusion power plants found that they emit less CO₂ than photovoltaic solar systems and just about double those from nuclear fission reactors. 

The 2 main environmental concerns associated with nuclear fission are nuclear waste and uranium mining. 

• Nuclear waste products generated from nuclear fission reactions include uranium mill tailings, spent (used) reactor fuel, and other radioactive wastes, all of which can remain hazardous for many thousands of years.
• Uranium mining can also contaminate the environment with radioactive dust, radon gas, water-borne toxins, and increased levels of background radiation. 

Ways to minimize the negative environmental impacts of nuclear fission include the proper handling, transportation, storage, and disposal of radioactive waste to ensure that it does not leach into the environment. Proper containment and ventilation of mines can also help make the process of uranium mining safer for the environment.

On the other hand, nuclear fusion is much safer for the environment when compared to nuclear fission because the waste from nuclear fusion is stable and has a relatively short half-life.

A nuclear fusion reaction does not produce long-lived nuclear wastes. The only byproducts are helium (an inert gas) and tritium. Tritium is classified as low or intermediate-level nuclear waste, which is significantly less dangerous and radioactive than the high-level nuclear waste (e.g., uranium mill tailings and spent (used) reactor fuel).

In addition, the radioactive byproducts of fusion (tritium) are relatively short-lived when compared to the byproducts of nuclear fission (uranium). This is because tritium has a half-life of only 12 years, whereas the half-life of uranium is 700 million years. This means fusion byproducts are less radioactive for a significantly shorter amount of time, making it safer for the environment.

How Safe Is Nuclear Power When It Comes to the Energy Grid and Infrastructure

Nuclear power is not only safe, but it is also a beneficial addition to our energy grid and supporting infrastructure. 

Nuclear power is a centralized energy source, meaning electricity is generated at a large scale at one location and then transmitted to wherever it is needed. Centralized energy sources are incorporated into our traditional energy grid in the following manner:

1. Power plants generate electricity
2. Transformers step up voltage for transmission
3. Transmission lines transport electricity over long distances
4. Neighborhood transformer steps down voltage
5. Transformers on poles step down electricity before it enters houses

Typically, centralized systems negatively impact the environment because they largely depend on fossil fuels (i.e., coal, oil, natural gas) to generate electricity. These materials release toxic greenhouse gasses into the atmosphere which gradually break down the ozone layer.

But nuclear power is one of our cleanest sources of energy, generating only 12 grams of CO₂ equivalent per kWh of electricity produced, the second lowest out of all fuel types.

Increasing nuclear power usage can displace some of the energy currently provided by fossil fuels, which is safer and is a net benefit for our planet. 

Nuclear power can also compensate for shifts in renewable energy output:

• Two of the main drawbacks associated with renewable energy are intermittency and lower levels of energy output because renewable energy sources are often location-specific and influenced by weather patterns.
• Nuclear power being a centralized energy source means it is more predictable, dependable, and constant.

How Safe Is Nuclear Power Across Its Life-Cycle

To understand how safe nuclear power is, we must look at its life cycle and how safe each stage is. This includes assessing the safety of nuclear power’s building, operating and maintaining, and building back stages. 

How Safe Is Nuclear Power in the Building Stage

The building stage of nuclear power includes constructing the power plant and reactors, gathering and processing the input materials, and transporting the materials to the power plant.

Safe work practices and proper training can mitigate the most common workplace hazards associated with the building stage of nuclear power, including lifting, trips, falls, electricity, and ladders.

Nuclear power facilities also contain thousands, if not millions, of components including:

• Containment buildings, reactor vessels, steam lines, pumps, and cooling towers for nuclear fission
• Magnets, coils, antennas, diagnostic instruments, cryopumps, thermal shields, and beam injectors for nuclear fusion

Nuclear fission also comes with additional occupational health and safety hazards associated with uranium mining. Uranium is considered potentially hazardous due to its emission of ionizing radiation. Controlling radon dust, limiting direct exposure to radiation, and enforcing strict hygiene standards can lower the risks associated with uranium mining. 

Lastly, constructing the transmission lines, transformers, and substations required for delivering electricity to consumers also comes with a carbon footprint and associated hazards.

How Safe Is Nuclear Power in the Operating and Maintaining Stage

The operating and maintaining stage of nuclear power includes the process by which atomic nuclei are either split apart or fused together to generate energy.

Nuclear power is generally considered safe to operate and maintain if proper precautionary measures are followed. 

The main safety concern associated with nuclear fission is the possibility of uncontrolled radioactive material release, leading to off-site contamination and radiation exposure. But in the history of fission, there have been only 2 major nuclear accidents in the roughly 70 years of its history, the Chernobyl and Fukushima disasters.

There are also numerous safety measures in place to protect the safety of nuclear fission power plant workers, including:

• Remote control of operations taking place inside nuclear reactor cores, areas with the highest levels of radiation
• Physical shielding mechanisms 
• Time limits for workers exposed to areas with high levels of radiation
• Continuous monitoring of radiation levels in all areas of a nuclear power plant
• Robust monitoring equipment and regular testing to detect mechanical failures

Nuclear fusion is considered even safer to operate and maintain than nuclear fission. Because nuclear fusion is not based on a chain reaction, the fusion reaction can come to a halt in a fraction of a second, and there is no possibility of uncontrolled radioactive material release. 

Because fusion is still in the research and development stage, there are no concrete safety standards yet specifically for fusion. But we can further increase the safety of nuclear fusion by applying relevant safety standards of nuclear fission to nuclear fusion in the meantime.

How Safe Is Nuclear Power in the Building Back Stage

The building back stage of nuclear power involves decommissioning the nuclear facility and restoring/repurposing the land.

Nuclear power is generally considered safe in the building back stage. 

The main safety concern associated with the building back stage involves the handling and disposing of nuclear waste. 

• For nuclear fission, spent nuclear fuel in the reactor core is highly radioactive and must be removed and submerged in water for several years on-site. 
• For nuclear fusion, plasma vessel walls become radioactive when high-energy neutrons activate them. 

Although most components of a nuclear power plant are not radioactive or are only lightly contaminated, direct contact with spent nuclear fuel or plasma vessel walls can cause radiation sickness and death. Upon decommissioning the facility, spent fuel and vessel walls must be temporarily stored until the radioactivity decreases enough to not be a risk.

Nuclear fusion is considered safer than fission at this stage because the radioactive byproducts of fusion (tritium) are relatively short-lived when compared to the byproducts of nuclear fission (uranium). This is because tritium has a half-life of only 12 years, whereas the half-life of uranium is 700 million years. This means it takes less time to decommission, remediate, and restore nuclear fusion power plant sites.

How Safe Is Nuclear Power in Comparison to Other Types of Energy

Nuclear power is one of our safest forms of energy (fossil fuels and renewable energy included). 

Nuclear fission has a death rate of 0.03 deaths per terawatt-hour of electricity produced, the second-lowest out of all energy types. This includes deaths resulting from accidents and air pollution.

To put it into perspective:

• A town powered entirely by nuclear fission with a population of 150,000 that uses one terawatt-hour of electricity per year would experience only 1 death from nuclear fission every 33 years. 
• If that same town was powered entirely by coal, roughly 1,250 people would die prematurely in the same amount of time, mostly from air pollution – that’s about 25 people every year.
• In short, nuclear fission results in 99.9% fewer deaths than brown coal.

Nuclear fusion is also considered to be one of our safest forms of energy because fusion cannot cause a nuclear accident or be used to produce nuclear weapons. 

• Nuclear fusion reactions are not based on chain reactions and therefore cannot cause a nuclear accident. 
• Nuclear fusion does not use fissile material (e.g., uranium and plutonium) in its reactor, so there is no opportunity for the uncontrolled release of radioactive material. 

Overall, nuclear power is one of our safest forms of energy because it boasts one of the lowest death rates per unit of electricity generation from accidents and air pollution.

What Are The 7 Pros and 4 Cons of Nuclear Power

Nuclear power has a low carbon footprint, protects air quality, is extremely energy dense, generates few waste products, and promotes energy independence and energy security. In addition, nuclear fusion cannot cause a nuclear accident or be used to produce nuclear weapons.

Nuclear power generates nuclear waste with varying radioactivity. In addition, nuclear fission is a nonrenewable resource and nuclear fusion is still in the research and development phase because the fusion reaction is very difficult to start and maintain.

What Are the 7 Pros of Nuclear Power

Nuclear power has a low carbon footprint, protects air quality, is extremely energy dense, generates few waste products, and promotes energy independence and energy security. In addition, nuclear fusion cannot cause a nuclear accident or be used to produce nuclear weapons.

What Are the 4 Cons of Nuclear Power

Nuclear power generates nuclear waste with varying radioactivity. In addition, nuclear fission is a nonrenewable resource and nuclear fusion is still in the research and development phase because the fusion reaction is very difficult to start and maintain.

How Effective & Efficient Is Nuclear Power

In terms of effectiveness, nuclear power effectively generates nuclear energy by having a low carbon footprint, protecting air quality, being energy dense, generating few waste products, and promoting energy independence and security.

In terms of efficiency, nuclear power uses energy-dense input materials to efficiently generate nuclear energy and has a small land-use carbon footprint when compared to other energy types.

Nuclear power is effective because:

• Nuclear power has become one of our largest global contributors of carbon-free electricity, accounting for roughly 10% of the world’s energy generation. 
• Nuclear power has the second-lowest carbon footprint out of all fuel types. On a life-cycle basis, nuclear power emits 12 grams of CO₂ equivalent per kWh of electricity produced.
• Nuclear power produces a fraction of the pollution and toxic chemicals that fossil fuels produce, helping to protect air quality.
• Nuclear power is extremely energy dense, so you don’t need a lot of it to create a lot of energy.
• Nuclear power produces substantially less waste than other forms of energy.
• Nuclear power can help us transition away from fossil fuels and towards an energy-independent future.
• Nuclear fusion reactions are not based on chain reactions and therefore cannot cause a nuclear accident

However, nuclear power can lack effectiveness because:

• Nuclear fission is classified as a nonrenewable resource. Once we run out of Uranium-235, we won’t be able to generate the nuclear fission reaction anymore.
• Nuclear fusion is still very much in the research and development phase because the fusion process is difficult to start, maintain, and control.

Nuclear power is efficient because:

• Nuclear power uses fuel that is extremely energy dense, so you don’t need a lot of it to create a lot of energy. 
• Nuclear power has a small land-use footprint, using only 0.3 square meters of land per megawatt-hour of electricity produced, the lowest out of all energy types.

However, nuclear fusion can lack efficiency because the two main challenges to fusion are maintaining the reaction and generating more energy from the reaction than was required to start the reaction.

How Can Nuclear Power Help Mitigate Climate Change

Climate change is a severe, long-term consequence of fossil fuel combustion. If left untreated, atmospheric CO₂ can remain there for tens of thousands of years and exacerbate the negative effects of climate change. Nuclear power emits less CO₂ upon operation than fossil fuels and can therefore reduce our total emissions. 

How Is Climate Change Defined

Climate change is arguably the most severe, long-term global impact of CO₂. Every year, we emit approximately 37 billion tons of CO₂. The carbon found in fossil fuels reacts with oxygen in the air to produce CO₂. 

“Climate change: changes in the earth’s weather, including changes in temperature, wind patterns, and rainfall, especially the increase in the temperature of the earth’s atmosphere that is caused by the increase of particular gasses, especially carbon dioxide.”

Oxford Dictionary

When carbon enters the atmosphere, it absorbs sunlight and solar radiation, trapping the heat and acting as an insulator for the planet.

Since the Industrial Revolution, Earth’s temperature has risen a little more than 1 degree Celsius (°C), or 2 degrees Fahrenheit (°F). Between 1880-1980 the global temperature rose by 0.07°C every 10 years. This rate has more than doubled since 1981, with a current global annual temperature rise of 0.2°C, or 0.36°F, for every decade. 

How Does Nuclear Power Specifically Help Mitigate Climate Change

The global average concentration of CO₂ in the atmosphere today registers at 419 parts per million (ppm), the highest ever recorded. Nuclear power can help lower this concentration because it can replace some of the burning of fossil fuels (e.g., coal, oil, natural gas) with a cleaner form of renewable energy.

Nuclear power helps to avoid 1.5 gigatons of greenhouse gas (GHG) emissions per year and 180 billion cubic meters of global gas demand per year. In the past 50 years, nuclear power has helped avoid over 70 gigatons of GHG emissions. 

Increasing nuclear power energy usage can reduce CO₂ emissions, and the more we reduce CO₂ emissions, the more we combat the negative effects associated with climate change including temperature rise, sea-level rise, ice melting, and ocean acidification. When these rates are slowed, the earth’s biodiversity does not have to struggle to adapt to temperature and pH changes. People will not be displaced due to the flooding of coastal areas. And icebergs will continue to provide climate regulation. 

Final Thoughts

At a holistic level, nuclear power is considered to be a safe form of energy in terms of human and animal health, the environment, and the energy grid and supporting infrastructure. It has a low carbon footprint and can be a beneficial addition to our power grid that can displace fossil fuel usage and improve air quality.

Nuclear power is also considered to be safe during its entire life cycle (building, operating and maintaining, and building back stages). Radiation exposure and common workplace hazards can be mitigated by proper training, safe work practices, and appropriate nuclear containment and disposal methods. Nuclear fusion has the added safety benefit of not being able to cause a nuclear accident or be used to produce nuclear weapons.

Forging a sustainable planet for future generations will require us to increase clean energy usage, and nuclear power is a great place to start. 

Stay impactful,

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