Download Nuclear Energy

Section 3
Inside the nucleus of the atom contains
protons and neutrons.
 Nuclear reactions involves tremendous
amounts of energy.
 Two types of nuclear reactions:
1. Fission
2. Fusion

Nuclear fission is the splitting of an atom’s
nucleus into two smaller nuclei.
The fuel is a large unstable atom such as
Uranium-235.
When the neutron hits the U-235 nucleus, the
nucleus splits apart into two smaller nuclei
and 2 or more neutrons.

If a nuclear chain reaction is not controlled,
the released energy causes a huge explosion.
(atomic bomb)

If a nuclear chain reaction is controlled, the
energy is released as heat, which can be used
to generate electricity.
Controlled nuclear fission.
The heat released from the reactions is used to
change water into steam.
The steam then turns the blades of a turbine to
generate the electricity.
 Two main parts to the power plant:
 Reactor Vessel
 Heat Exchanger
Nuclear power plants generate much of the
worlds electricity.(20% in the U.S.)

Meltdowns (Chernobyl, Ukraine)
1. Fuel rods produced too much heat,
2. Increase steam pressure,
3. Explosions occurred,
4. Radioactive materials escapes.


Radioactive waste disposal
Nuclear Fusion is the combining of 2 atomic
nuclei to produce a single larger nucleus.
 Advantages:
1. It produces more energy per atom than
nuclear fission.
2. It is readily available.
3. It is safer
4. Less polluting than nuclear fission.

Disadvantages:
1. Scientists have not yet been able to control
a large-scale fusion reaction.

No material has been found that could serve as
a reactor vessel under high pressure.
Scientist believe one day they will succeed and
produce a clean, cheap energy source.