08. P3 Generating Electricity

Question 1

Define - Acid rain

Answer 1

Environmental problem caused by sulfur dioxide (which is released by burning fossil fuels)

Question 2

Define - Base load

Answer 2

Constant amount of power generated by power stations. Usually supplied by stations with large start-up times (coal, nuclear etc.) andother methods used tomeet the variations in demand.

Question 3

Define - Biofuel

Answer 3

A carbon-neutral, renewable type of fuel obtained from living or recently living organisms (wood is common example)

Question 4

Define - Carbon Capture and Storage

Answer 4

Stops the release of carbon dioxide from fossil fuel power stations. Known as CCS.

Question 5

Define - Carbon-neutral

Answer 5

Only releases the same amount of carbon dioxide that it absorbed during its lifetime, so there is no overall increase in carbon dioxide by burning it.

Question 6

Define - Fossil Fuels

Answer 6

Coal, oil and gas. Finite fuels which have been produced over millions of years.

Question 7

Define - Geothermal energy

Answer 7

Uses heat from the energy released by radioactive substances deep within the Earth.

Question 8

Define - Hydroelectric power

Answer 8

Uses a dam that directs water through a turbine to generate electricity.

Question 9

Define - National grid

Answer 9

Network of cables and transformers that transfers electricity around the country.

Question 10

Define - Nuclear fission

Answer 10

Splitting nuclei to release energy. Used in Nuclear power stations.

Question 11

Define - Solar cell

Answer 11

Panel that converts energy from the sun into electrical energy. Also called a photovoltaic cell.

Question 12

Define - Solar heating panel

Answer 12

Panel that converts energy from the sun to thermal energy by heating water which is passing through the pipes.

Question 13

Define - Solar power tower

Answer 13

Uses many mirrors to reflect sunlight onto a water tank on top of a tower, steam produced turns turbines andthen generators.

Question 14

Define - Start-up time

Answer 14

Time taken for power stations to start up. Nuclear has the longest, then coal, then oil, then natural gas. Hydroelectric has shortest start up time

Question 15

Define - Step down transformer

Answer 15

Device for making the voltage of an AC supply lower.

Question 16

Define - Step up transformer

Answer 16

Device for making the voltage of an AC supply higher.

Question 17

Define - Tidal power

Answer 17

Uses trapped high tides to force water through a turbine to generate electricity.

Question 18

Define - Turbine

Answer 18

Rotates when steam or water is pushed through it. Used to drive a generator.

Question 19

Define - Wave power

Answer 19

Uses the movment of water waves to generate electricity by turning turbines and generators.

Question 20

Define - Wind power

Answer 20

Uses the wind to turn turbines/generator, and generate electricity.

Question 21

Advantages of biofuels

Answer 21

Renewable, Carbon neutral, reliable

Question 22

Advantages of Geothermal energy

Answer 22

Free fuel costs, No carbon dioxide released, renewable, reliable

Question 23

Advantages of hydroelectric power

Answer 23

No pollution, short start up time, fuel is free, reliable

Question 24

Advantages of nuclear power

Answer 24

Uranium is highly available(for now) and reliable, Lots of energy released per kg of fuel, No greenhouse gases

Question 25

Advantages of overhead cables

Answer 25

Cheaper to install and repair, easy to access so quicker, natural cooling by air, Thinner cables used

Question 26

Advantages of tidal barrages

Answer 26

No pollution, Reliable, Free fuel costs

Question 27

Advantages of underground cables

Answer 27

Not affected by bad weather, hidden, doesn't harm low flying aircraft, reduced risk of shock

Question 28

Advantages of wave power

Answer 28

No carbon dioxide or carbon particulates emitted, renewable source, no fuel costs

Question 29

Advantages of wind power

Answer 29

No carbon dioxide or carbon particulate emitted, renewable source, no fuel costs

Question 30

Disadvantages of biofuels

Answer 30

Large areas of land needed to grow fuel, large amounts of fuel needed to match a fossil fuel output.

Question 31

Disadvantages of geothermal energy

Answer 31

Only possible in volcanic areas sos uitable sites difficult to find, expensive to build

Question 32

Disadvantages of hydroelectric power

Answer 32

Flood a valley, loss of habitat, high build costs

Question 33

Disadvantages of nuclear power

Answer 33

Produces nuclear waste, expensive to build, high safety costs, non-renewable

Question 34

Disadvantages of underground cables

Answer 34

Expensive to install and fix, takes longer to install, Insulation needed to reduce risk of electrocution

Question 35

Disadvantages of overhead cables

Answer 35

Eye-sore, Damages landscapes, Can be damamged by weather, Easy access allows possible vandalism, Hazard to low flying air crafts

Question 36

Disadvantages of solar cells

Answer 36

Only works at day time, unreliable, high initial costs (although these are getting cheaper)

Question 37

Disadvantages of tidal barrages

Answer 37

Prevents boat access, can affect habitat, high cost to build

Question 38

Disadvantages of wave power

Answer 38

Spoils view , hazard to boats, unreliable (no wind = no waves)

Question 39

Disadvantages of wind power

Answer 39

Spoils view(visual pollution), noise pollution, unreliable, large number needed (600ish) to produce same energy as a standard coal power station

Question 40

Decribe the processes in a fossil fuel power station

Answer 40

Fuel is burnt to release heat energy and boils the water, Water turns to steam, steam turns turbines, which turns generator to generate electrical energy

Question 41

Define - Finite

Answer 41

Will run out

Question 42

How is nuclear power made safe?

Answer 42

Reactors are cooled by water, fission slowed down by control rods, Fission reaction encased in steel vessels and thick concrete.

Question 43

Non-renewable

Answer 43

Resource that will run out once they're used as they cannot be used again eg coal and oil

Question 44

Renewable

Answer 44

A resource that can be replaced/regenerated and will never run out eg solar and wind

Question 45

The national grid

Answer 45

The network of transformers cables and pylons that carry energy across the country

Question 46

Advantages of solar cells?

Answer 46

Free fuel costs, No carbon dioxide released, renewable

Question 47

What are tidal barrages?

Answer 47

Dams built across river estuaries which control the flow of tidal water

Question 48

What does nuclear power stations use as fuel?

Answer 48

Uranium (and some plutonium)

Question 49

Briefly describe nuclear fission in power stations

Answer 49

Nuclei splits into two smaller nuclei, releasing neutrons, and energy

Question 50

Which non-renewable resource has the quickest start up time?

Answer 50

Natural gas

Question 51

Why is the voltage stepped down?

Answer 51

The voltage is stepped down before it reaches the homes because it is less dangerous to use in homes

Question 52

Why is the voltage stepped up?

Answer 52

Higher voltage = lower current through wires = less heat loss in wires