Nuclear Energy

Where does nuclear energy come from?

• Nuclear energy is energy found in the nucleus of an atom. Matter can be converted to Energy (Albert Einstein)

E = mc2

• In order to use the nuclear energy, it must be released. It can be released through nuclear fission or nuclear fusion.

Fission vs. Fusion

• In Nuclear Fission, atoms are split to form smaller atoms. Nuclear power plants use this method to produce electricity.

• In Nuclear Fusion, atoms are combined to form larger atoms. This is how the sun produces energy.

• It is not know if nuclear fusion will ever be a commercially viable option.

Uranium

• The most commonly used atom in Nuclear Power Plants is uranium. It is a nonrenewable resource, but is very abundant in rocks. The particular isotope used is called U-235. This isotope is pretty rare.

• Most of the uranium used in the US is mined in the western United States.

Nuclear Reactors

• In a nuclear reactor, a neutron hits a uranium atom splitting it and releasing energy and more neutrons. These newly released neutrons go on to hit more atoms, splitting those and setting off a chain reaction.

Reactors in the US

• There are 65 Nuclear Power Plants and 100 nuclear reactors in the United States (most east of the Mississippi River) The last one was completed in 1996 and there are five scheduled to be built. Those five were all started in the 1970’s, but construction was cancelled. Four older ones were closed in 2013 due to high maintenance costs.

Inside a Reactor

• Fission takes place inside the reactor of a nuclear power plant. At the center of the reactor is the core, which contains the uranium fuel.

Inside a Reactor

• The uranium fuel is formed into ceramic pellets. The pellets are about the size of your fingertip, but each one produces roughly the same amount of energy as 150 gallons of oil. These energy-rich pellets are stacked end-to-end in 12-foot metal fuel rods. A bundle of fuel rods, sometimes hundreds, is called a fuel assembly. A reactor core contains many fuel assemblies.

Nuclear Reactors

• The heat given off during fission in the reactor core is used to boil water into steam, which turns the turbine blades. As they turn, they drive generators that make electricity. Afterward, the steam is cooled back into water in a separate structure at the power plant called a cooling tower. The water can be used again and again.

Nuclear Energy and the World

• Nuclear Energy accounts of 15% of the world’s electricity.

• Nuclear power produces no carbon dioxide or other pollutants. However, the process of mining and processing Uranium requires a large amount of energy.

• They do produce radioactive waste that are harmful to humans for thousands of years