APES 6.6 Nuclear Power

Enduring Understanding:

Humans use energy from a variety of sources, resulting in positive and negative consequences.

Learning Objective:

Essential Knowledge:

Nuclear power is generated through fission, where atoms of Uranium-235, which are stored in fuel rods, are split into smaller parts after being struck by a neutron. Nuclear fission releases a large amount of heat, which is used to generate steam, which powers a turbine and generates electricity.
Radioactivity occurs when the nucleus of a radioactive isotope loses energy by emitting radiation.
Uranium-235 remains radioactive for a long time, which leads to the problems associated with the disposal of nuclear waste.
Nuclear power generation is a nonrenewable energy source. Nuclear power is considered a cleaner energy source because it does not produce air pollutants, but it does release thermal pollution and hazardous solid waste.
Three Mile Island, Chernobyl, and Fukushima are three cases where accidents or natural disasters led to the release of radiation. These releases have had a short-and long-term impacts on the environment.
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.

Process

An incident neutron is shot at a very high speed towards a U-235 nucleus
The nucleus is ripped apart, releasing energy and high speed neutrons
This causes a chain reaction where those runaway neutrons split other nuclei, and so on

The hazardous waste produced is present for a very long time
There is thermal pollution
The initial cost can be billions
There is mining involved for construction and Uranium
- Mining Uranium is also an extremely dangerous process
It is nonrenewable
There are rare but notable chances of nuclear meltdown

Nuclear energy comes from breaking down U-235
The isotope is always losing energy, but this energy is radioactive and therefore very dangerous
Once U-235 has broken down, it remains radioactive but can no longer be used
It gathers neutrons, becoming heavier like plutonium
It will remain radioactive for up to 24,000 years (10 half lives)
There is nothing we can do with it except store it safely and hope no radiation leaks out

We have to find a place to store the material for a long time
Often times we store the waste on site, deep underground
More sites means more chances of radioactivity leaking into the environment
A federal site called Yucca Mountain, Nevada, was commissioned to hold nuclear waste
- Due to the Not In My Backyard movement/concern, it did not fulfill this purpose
- There were other concerns as well