Sustainable Idaho: Nuclear Introduction
Sustainable Idaho looks at the economic, environmental, and societal elements of sustainability, and one of the biggest motivators to shift towards sustainable practices is addressing climate change. The science is clear that climate change is caused by burning fossil fuels which creates heat trapping greenhouse gases like CO2. Scientists at the Intergovernmental Panel on Climate Change have set 1.5 degrees Celsius as the threshold where warming imposes even greater risks than today.
Climate change is a key issue of our generation and Sustainable Idaho will begin exploring ways that Idaho can begin to make the green energy transition. Therefore, we are starting a new series this week on nuclear energy. This series is expected to be split into four parts that cover the basics of nuclear processes, nuclear potential, disadvantages, and finally, nuclear energy economics. In this episode, we cover the nuclear energy process.
First, nuclear energy is produced when uranium atoms are split in a nuclear reaction. To get uranium, it must be mined. As explained online by the World Nuclear Association, uranium is a naturally occurring element and is usually mined in open pit or underground mines. To start off our nuclear series, we invited Dr. Dunzik-Gougar, a nuclear engineering professor at Idaho State University, to explain the science behind nuclear energy. She began by detailing out the mining and enrichment process for us.
Before uranium can be used to produce power, it needs to be enriched with more uranium 235 atoms to be fissionable, or able to be split apart to create mass amounts of energy. Dr. Dunzik-Gougar explained that uranium is just slightly radioactive before it goes into a reactor, but after being used for 5 or 6 years it comes out very radioactive. Now, there are two main different types of radioactive waste produced from nuclear plants: low level and high level waste. Low level waste includes materials used around the nuclear site, such as mops, clothing and filters. This waste is shipped to and processed at one of the four low-level waste sites in the U.S. High level waste is most often spent fuel which is a term for the uranium after it has passed through its lifecycle in the reactors.
According to the United States Nuclear Regulatory Commission, “High-level wastes are hazardous because they produce fatal radiation doses during short periods of direct exposure. For example, 10 years after removal from a reactor, the surface dose rate for a typical spent fuel assembly exceeds 10,000 rem/hour – far greater than the fatal whole-body dose for humans of about 500 rem received all at once.” This quote highlights that high doses of radiation can be deadly but moderate doses also pose dangers like harm to fetal development or damaging the DNA of cells, which can increase the risks of cancer. Dose amounts are key; for example, low amounts pose very limited risks and are a natural part of our world.
However, the dangers from spent fuel made us curious as to where this highly radioactive waste goes? In addition to Dr. Dunzik-Gougar, we invited Dr. Gehin from the Idaho National Laboratory to help us learn about nuclear power. Dr. Gehin, the Chief Scientist for the Nuclear Science and Technology directorate, recaps the difference between radioactive wastes and explains where spent fuel goes when it is done being used. As of right now, there are no permanent nuclear waste storage sites in the world. This is in part due to how long it takes material within the spent fuel to decay, which ranges between a few to thousands of years, depending on the type of isotope comprising the spent fuel. This is one of the major contributors to controversy over nuclear energy.
While there are many concerns surrounding the waste storage and plant safety, nuclear energy has potential as a cleaner, low fossil fuel, energy source that could meet base load needs. Catch our episode next week as we explore the potential of nuclear energy with both guests from this episode, Dr. Dunzik-Gougar and Dr. Gehin.
Join us for Sustainable Idaho, every Tuesday morning at 7:35 am