Energy Matters

Fossil fuels

finite

• Use insulation in wall, ceilings, etc
• Get double glazing windows
• Switch appliances off when finished - do not leave them on standby
• Use draft excluders

• Walk/ use public transport to get to work
• Switch appliances off

• Share cars
• Encourage public transport
• Travel at an efficient speed
• Walk short distances instead of taking the car

• Coal
• Oil
• Natural Gas
• Peat

• Uranium
• Plutonium

• Solar energy
• Advantage - A clean source of energy (no waste/pollutant gases or substances)
• Disadvantage - expensive and can only work during daylight hours
• Wind Energy
• Advantage - conditions for wind turbines are favourable in Britain
• Disadvantage - It is not always windy and turbines are unsightly and noisy
• Wave Energy
• Advantage - Reliable
• Disadvantage - Difficulties with construction, maintenance and energy conversion
• Geothermal energy
• Advantage - clean source of energy
• Disadvantage - dependant on suitable sites
• Hydro-electric
• Advantage - renewable, reliable and a clean source of energy
• Disadvantage - there are environmental objections to the building of dams
• Biomass
• Advantage - renewable
• Disadvantage - Growth is too slow to provide large amounts of fuel

Chemical to heat

Nuclear to heat

Gravitational potential energy to kinetic

Nuclear fission reactions

• In a nuclear reactor, a neutron is fired at the nucleus of a uranium or plutonium atom causing the atom to break up into two fission fragments. (Every time this happens heat energy is released). Two or three more neutroms are also released from the split atom.
• The neutrons which are released hit other uranium or plutonium atoms causing them to break up and release more neutrons which go on to hit other uranium or plutonium atoms. This is known as a chain reaction

They produce radioactive waste

The water which runs down the dam is pushed back up to the top so it can be used again. This is usually done at night when the demand for electricity is less and nuclear power stations are producing electricity which nobody will use. The electricity from the nuclear power station is used to push water back up the dam so the electriciy is not wasted

heat or sound

• By moving a metal wire up or down between the opposite poles of a bar magnet
• By winding the metal wire into a coil then moving a bar magnet into or out of the coil

• Use a stronger magnet
• Move the wire or magnet faster
• Wind more turns of wire on the coil

To change the size of an a.c. voltage

• Primary coil
• Soft iron core
• Secondary coil

increase

decrease

• Electricity from a power stations is sent to a step-up transformer which makes the voltage larger but the current smaller
• The electricity is sent around the country through overhead power lines which are held up by pylons - the connection of pylons across the country is called the National Grid
• The electricity arrives at a step-down transformer which makes the voltage smaller but the current larger.
• The electricity is passed to our homes via a substation through undergound power lines

how hot or cold something is

Degrees celcius (°C)

more

• Conduction - happens mainly in solids. Particles vibrate against each other passing heat energy from one particle to the next
• Convection - Happens in liquids and gases. Hot particles move up while cold particles move down. This creates a convection current
• Radiation - Does not involve particles. Infra-red heat energy travels through gases and liquids as waves

• Insulate the upstairs ceilings
• Put foam in the walls
• Wall-to-wall carpets
• Double glazing

• Curtains
• Seal doors and windows
• Insulation

• Put shiny surfaces in your insulation
• Paint your house white

The amount of heat energy needed to change the temperature of 1kg of the substance by 1 °C

state

It does not change