ERC: Lesson - Impacts of Nuclear Power (Topic 6.6) 📖

⏳ Estimated Reading/Watching Time: 11 - 13 minutes

Describe the effects of the use of nuclear energy on the environment.

 

Perceived Risk

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People tend to have strong opinions about nuclear power – they either think it is a great solution for a post-fossil fuel world, or they have huge concerns about the storage of waste and potential environmental impacts. Below are some of the advantages and disadvantages of nuclear power:

Advantages:

✅ only a little Uranium is needed to produce a lot of energy

✅ low environmental impacts (if no accidents occur)

✅ Much lower CO₂ produced than with fossil fuels

✅ no sulfur dioxide or particulate emissions

✅ less waste produced than in coal power plants

Disadvantages:

❌ high economic cost to build and maintain power plants

❌ thermal pollution

❌ relatively low energy yield

❌ high environmental impact if an accident occurs

❌ power plants have a relatively short lifespan (around 40 years)

❌ large amounts of radioactive waste that must be stored in a safe place for thousands of years

❌ high cost to decommission, clean and make safe, when they have reached the end of their lifespan

Some of these advantages and disadvantages are difficult to assign a value to so we can talk about them in terms of risk. Merriam-Webster defines risk as “the possibility of loss or injury.” Within risk, we consider both the probability of a loss or injury occurring and also the severity of that loss or injury.

With nuclear power, the probability of a loss or injury is typically very low because of all the redundancies in place to deal with possible situations. The severity of a loss or injury, should they occur, is enormous when it comes to nuclear power.

Because of the severity of risk associated with nuclear power, many people find that risk unacceptable even though the probability of an accident occurring is very low.

This perceived risk (how the public perceives a risk) has caused most countries to stop building nuclear power plants, for now. Perhaps as we get better at preventing and dealing with potential nuclear accidents, we will build more nuclear power plants. For now, though, few, if any, nuclear power plants are being built.

Many people wonder, “Are the benefits associated with nuclear power worth the potential cost should there be an accident?” What do you think?

 

Nuclear Power Plant Accidents

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We knew the dangers associated with radioactive materials, so nuclear power plants were carefully built with many redundancies in place to cope with the possibility of accidents that might result in widespread damage and injury. Although nuclear power holds many promises, there have been several major events that have caused people to re-think their opinions about the safety of this energy resource. In some cases, it was a near-miss but in other cases, major, long-lasting damage occurred. 

The danger in nuclear reactors is when a reactor experiences a loss of coolant accident (LOCA).  This can result in the core overheating.  If this happens, the reaction will proceed uncontrollably and would release enough heat to melt the materials in the core, which is known as a meltdown.  The core has backup cooling systems to keep the reactor immersed in water in case a leak occurs.  All of this is also housed in a thick concrete containment building, which is thought to protect the outside from radioactivity.

Despite all of the redundancies put into place, there have been some significant accidents at nuclear power plants. There has also been some loss of human life, widespread contamination of surrounding areas, and air and water pollution caused by the release of radioactive materials. Explore the tabs below to learn more about the three largest nuclear power plant accidents:

Three Mile Island, Chornobyl, and Fukushima are three cases where accidents or natural disasters led to the release of radiation. These releases have had short- and long-term impacts on the environment.

 

Half-Life

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One of the major issues with nuclear energy is dealing with materials and wastes that can remain radioactive and dangerous for thousands of years. Scientists use the term half-life to indicate the length of time it takes for a given type and amount of nuclear material to decay and lose its radioactivity.  It is a measure of how quickly a substance decays. Some elements have half-lives that are fractions of a second and others have half-lives that are thousands of years.

The National Regulatory Commission (NRC) defines a half-life as “The time in which one half of the atoms of a particular radioactive substance disintegrate into another nuclear form. Measured half-lives vary from millionths of a second to billions of years. This is also called physical or radiological half-life.”

 

 

 

 

Half-Life Calculations

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Calculating half-lives involves both math and logic. Math comes in handy when working with the associated numbers, but logic is needed to figure out the endpoint of a half-life calculation.

Let’s try a couple of examples:

A radioactive element's half-life can be used to calculate a variety of things, including the rate of decay and the radioactivity level at specific points in time.

 

You should understand the controversy surrounding nuclear power generation.

You should know the big takeaways from each nuclear disaster.

You should know how to calculate half-life on the AP exam. You will get a calculator, but you won't be given a formula.

 

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