3-8 Nuclear Power Generation

1. 3-8 Nuclear Power Generation (11.3 pg 318-322)

2. Physicists figured out they could cause a self-propagating set chain reaction of nuclear fission reactions from a single neutron to create a lot of energy (Fig.1 p.318).

3. Although a single fission reaction produces a small amount of energy, a large number of reactions could produce a LOT of energy, but would also need to be controlled!

4. The first nuclear reactor was built in 1942 as an experiment (Fig.2 p.319).

5. It helped to highlight 5 major problems that needed to be overcome by any nuclear power plant: • Very concentrated radioactive material is needed. Natural uranium is not enough. • Fast moving neutrons need to be slowed down in order to react with a nucleus and cause fission. A moderator is a substance that slows the neutrons down enough. • There needed to be a minimum mass of radioactive fuel to absorb the neutrons. This amount is called the critical mass. • The reaction needs to be controlled. If it goes too fast it can overheat and explode. Too slow and it will stop altogether. • The final problem was how to deal with the massive amounts of heat produced. This problem was nicely solved by using it to boil water to generate steam to drive a turbine, which would generate electricity.

6. Canadian-developednuclear reactors are called CANDU reactors (CANDU =CANadian Deuterium and Uranium). • They use natural uranium as fuel and heavy water (deuterium water) as a moderator and coolant. • CANDU reactors are a type of pressurized heavy water reactor (PHWR); the other popular type of popular reactor is the pressurized water reactor or (PWR).

8. There are advantages and disadvantages to nuclear power facilities:

9. TED talk debate: Does the world ‘need’ nuclear energy? http://www.ted.com/talks/debate_does_the_world_need_nuclear_energy#t-30854