All About Nuclear Energy and Radiation
What is Radiation?
Radiation, in broad terms, is moving energy. When you drop a rock into water, you see waves radiating from the point of impact. Energy, in the form of heat and light, radiates from the sun. This energy from the sun is positive in that it warms us and helps us to see. It can also be harmful as the ultraviolet radiation from the sun can burn and damage skin.
The radiation from the sun and other sources such as x-rays and radio waves is known as ionizing radiation. Ionizing radiation has a level of energy high enough to cause the atom with which it interacts to become charged. Different types of ionizing radiation react with atoms at different levels of penetration. Some can cause severe damage so it is wise to monitor and control how much exposure we have. Radiation exposure from nuclear waste and uranium ores is virtually unavoidable since it is a part of our environment. At low levels, this exposure is not harmful. In fact, a handful of uranium ore has about the same amount of radiation as a bunch of bananas.
Radiation has also proven to be very beneficial. Radiation science is a field that has yielded many developments, especially in the medical field. X-rays are used every day to diagnose broken bones and other problems hidden to the naked eye. Other types of radiation technology such as mammography, nuclear medicine, and magnetic resonance imaging have saved the lives of many people.
Alpha, Beta and Gamma
Atoms are the smallest unit of matter. Certain atoms that can break down or transform into new ones are referred to as radioactive. To become stable, they emit particulate or electromagnetic radiation. This process is called radioactive decay. The emission of the energy from the atom can come in the form of gamma rays and/or an alpha or beta particulate. If the atom emits radiation in the form of an alpha or beta particle, a new element is created. This emission is called gamma, beta, and alpha radiation.
Alpha particles are doubly charged and comprised of two protons and two neutrons. This double charge along with slow sped and high mass, lead alpha particles to interact more freely than beta particles or gamma rays. This all adds up to the alpha particle having a low level of penetrating power. Externally, they can be stopped by the first layer of skin. Internally, they can be more damaging.
Beta particles move faster than alpha particles. They are singly charged and lighter, allowing them to travel at faster speeds. They can also penetrate deeper than alpha particles.
Gamma rays are an energetic form of light. They have more energy than any other wave on the electromagnetic spectrum. Gamma Rays have far more penetrating power than alpha or beta particles and can easily penetrate the human body. They are measured in units called the Sievert. Doses less than 100 mSv are not harmful.
- Your Average Annual Radiation Dose- This chart illustrates how much radiation we are exposed to form different everyday sources.
- Radiation Health Effects- This site offers general information about radiation and it’s effects on our health.
- Types of Radiation- A list of information about alpha, beta and gamma radiation elements.
- Radiation in Everyday Life-How do we experience radiation in our everyday activities? This site explains how.
What is Nuclear Energy?
Atoms are all around us. They make up everything we see, smell, and touch. The majority of the atom’s mass is in its center, the nucleus. The nucleus is comprised of protons and neutrons surrounded by a cloud of electrons. If circumstances warrant, the nucleus of an atom can split. This split is explained by Albert Einstein’s E=MC2. In the formula, M=the small amount of mass and C=the speed of light.
This concept was recognized for use as a weapon in the 1930s and 1940s. The Manhattan Project developed the technology to harness this energy for nuclear bombs. After World War II, a new use was found for this energy source. It was used to fuel submarines for over a year with no need to refuel. A commercial use was also developed as the energy was used to produce electricity.
Fission and Fusion
To understand nuclear energy, two fundamental processes must be considered. These are fission and fusion. Fission involves the splitting of large atoms into smaller atoms. The split comes from the atom being hit with a neutron. The impact causes the release of other neutrons which can split other atoms. This chain reaction of energy release is used to generate heat which, in turn, generates electricity.
Fusion is when two small atoms come together to form heavier atoms. This type of reaction can release more energy than is release via fission without the radioactive byproducts fission produces. Fusion has not yet been developed as a commercial application but research is underway to create an energy source form the fusion process.
Advantages of Nuclear Power
Nuclear power is ecological. The only emission from nuclear power plants is hot water. Spent nuclear waste can be an issue but not if it is disposed of properly.
A former NASA scientist, James Hansen, published a paper in 2013 outlining how nuclear energy has actually saved nearly two million lives by displacing air pollution. This preservation of life serves to outweigh any loss of life resulting from nuclear power related accidents.
Nuclear power can create energy independence and help countries reduce their oil addiction. Nuclear reactor design can be adapted to produce heat, electricity, and to prepare hydrogen to be used in fuel cells and desalinate water.
Disadvantages of Nuclear Power
The waste product when atoms split are the destabilized smaller atoms. It can take hundreds or thousands of years before they attain stability. Thus, this waste has to be kept out of the environment. This can be done, but it is not an easy task.
There have been three major accidents that have happened at nuclear power plants. These include Chernobyl, Three Mile Island and Fukushima. These accidents happened when the plants lost cooling for various reasons. Without cooling, cores melted and radiation was released into the atmosphere. The nearby public had to be evacuated and diseases have been linked to exposure.
Nuclear power plants require many complicated safety systems. These systems result in high initial costs to build a nuclear power plant. Once operational, costs tend to be lower compared to those for plants producing fossil fuels.
- Advanced Reactor Technologies – The Office of Nuclear Energy discusses advanced reactor technologies and the next generation of nuclear power plants.
- Hurricane Harvey and Nuclear Power- This article describes how nuclear reactors in Texas survived Harvey and makes the case for nuclear power.
- Three Mile Island- This article discusses the accident at Three Mile Island.
- History of Nuclear Energy- A timeline of the history of nuclear energy demonstrates the progress we’ve made.
Online Bachelor of Radiation Science Technology- Learn more.