Nuclear Energy

How does it work?

• Some atoms, (like Uranium), are so big that we can break them apart by shooting tiny particles at them.

• This process releases a LOT of energy, and starts a chain reaction.

How does it work?• In a nuclear

power plant, we use the energy from this reaction to heat up water and turn it into steam.

• The steam spins a turbine, which produces electricity.

How does it work?

• If we didn’t “slow down” this chain reaction, it would get to hot and melt through the container.

• We put “control rods” into the reactor to absorb the extra energy so that the reaction doesn’t make too much heat.

Nuclear Power facts• As of 2011, there were

443 operating nuclear power plants over the world in 47 countries.

• In 2009, nuclear energy was the source of 14% of the world’s electricity. (France >75%)

• In the US, 109 nuclear power plants supply 20% of our electricity.

Nuclear Power - Pros• It’s clean energy• It creates very little carbon

dioxide emission (saves 2 billion metric tons of CO2 per year)

• It is not a fossil fuel• It produces about one million

times more energy per unit weight than fossil fuels.

• A properly running nuclear power plant puts less radioactivity into the atmosphere than a coal plant

Nuclear power - Cons• Radioactive material is

dangerous to mine/purify/transport

• Radioactive waste must be disposed of very carefully (about 2000 metric tons per year from all plants on earth)

• Nuclear waste takes thousands of years to reach “safe” levels of decay.

• Waste must be guarded, which costs money

• Nuclear power plants can be dangerous in rare cases.

Nuclear power - Cons

• 3 mile island (1979)• Chernobyl (1986)• Japan (2011)