Nuclear Power | AQA A-Level Environmental Science Revision | Primrose Kitten

Nuclear power

The use of radioactive isotopes to release large amounts of heat energy through fission or fusion processes.

Fission

The splitting of large atomic nuclei into smaller fragments, currently used commercially.

Fusion

The joining of small atomic nuclei, not currently used for commercial energy supply.

Unstable isotopes

Atoms that emit radiation to restore balance to their ratio of protons and neutrons.

Heat energy

Produced in large quantities from a small mass of fuel in nuclear processes.

Electricity generation

Heat energy used to boil water, produce steam, spin turbine blades, and generate electricity.

Non-renewable

Nuclear power is non-renewable due to the long time it takes for uranium deposits to reform.

Energy density

Extremely high energy density in nuclear power sources.

Depletable

Nuclear fuels like uranium will eventually run out.

Intermittency

Controlled in nuclear reactors by managing power output.

Predictability

High predictability in nuclear power as reactor power output is controlled.

Critical mass

The mass needed to sustain a chemical reaction in a nuclear reactor.

Chain reaction

A self-sustaining reaction where the products of one reaction cause more reactions.

Nuclear meltdown

Build-up of colossal heat energy in a reactor, prevented by control rods absorbing free neutrons.

Control rods

Materials that absorb free neutrons in a reactor to control the chain reaction.

Nuclear moderators

Materials in a reactor that slow down neutron movement to enhance fission.

Advantages of nuclear power

High energy density, abundant uranium, and no greenhouse gas emissions.

Disadvantages of nuclear power

Expensive setup, public safety concerns, radioactive waste disposal challenges.

Half-life

The time taken for the radioactivity of an unstable isotope to decrease by half.

Environmental impacts of uranium extraction

Negative impacts include noise pollution, dust pollution, acid mine drainage, and spoil heaps.

New technologies for uranium extraction

Polymer adsorption: method to extract uranium from low-grade ores by adsorbing onto a polymer in seawater.

Polymer

Material used to extract uranium from seawater

Phosphate mining

Process extracting phosphate with trace uranium

Coal ash

Residue from coal combustion containing trace uranium

Breeder reactors

Reactors converting fertile fuels to fissile fuels

Fissile fuel

Fuel capable of sustaining nuclear fission

Isotopes

Atoms with the same number of protons but different neutrons

Thorium232

Fertile fuel converting to fissile uranium233 in reactors

Molten salt coolant

Coolant in reactors with higher heat capacity than water

Nuclear fusion

Process joining small nuclei to release heat energy

Deuterium

Isotope of hydrogen used in fusion reactions

Tritium

Isotope formed from lithium absorption of neutrons

Plasma

State of matter with removed electrons for fusion

Hydrogen fusion

Joining of deuterium and tritium to form helium

Toroidal reactors

Reactor design with lithium blanket to produce more fuel

Laser fusion

Fusion method using laser on frozen hydrogen isotopes