Generating Electricity

Question 0

How is the water heated in power stations

Answer 0

By burning fossil fuels

Question 1

How do most power stations work

Answer 1

• water is heated to produce steam
• the steam drives a turbine
• the turbine drives a generator that produces electricity

Question 2

What are fossil fuels

Answer 2

Long- dead biological material

Question 3

Why can a gas fired turbine be turned on very quickly

Answer 3

Because hot gases can turn the turbine directly and quickly, which turns the generator quickly

Question 4

What is a biofuel

Answer 4

A fuel obtained from living or recently living organisms- made from animal or plant oils

Question 5

Why are biofuels god to use in a gas fired power station

Answer 5

Because they are renewable

Question 6

What fuel is used In nuclear power stations

Answer 6

Uranium, sometimes plutonium

Question 7

What type of reaction happens in a nuclear reactor

Answer 7

Nuclear fission

Question 8

How does a nuclear power station work

Answer 8

By nuclear fission, which releases energy, the energy is used to heat water, turning it into steam

Question 9

Why are nuclear power stations more useful than fossil fuel stations

Answer 9

More energy is released per kilogram of uranium undergoing fission reactors than that from each kg of fossil fuel

Question 10

Give examples of renewable energy

Answer 10

• geothermal
• hydroelectric
• solar
• wind
• wave and tidal

Question 11

What Do we mean when we say a renewable energy source

Answer 11

These energy sources can never be used up

Question 12

How does a wind turbine generate electricity

Answer 12

Wind passing over the blades makes them rotate and drive a generator at the top of a narrow tower

Question 13

How does a hydroelectric power station work

Answer 13

Water is collected in a reservoir, this water is allowed to flow downhill and turn turbines at the bottom of a hill

Question 14

Why can hydroelectric power be used at times of high demand

Answer 14

At times of high demand the water can be pumped to the top of a hill to the reservoir, this means energy is stored. The water can then be released and fall through the turbines and transfer stored energy into electrical

Question 15

What is the stored energy in the top reservoir of a pumped storage system

Answer 15

Gravitation potential

Question 16

How does wave power work

Answer 16

The movement of the waves drive a floating turbine and turns a generator, then electricity is delivered to the shore by a cable

Question 17

How does tidal power work

Answer 17

A barrage is built across an estuary, which traps the water at each tide. When the water is released, it falls to reach the rest of the sea level and drives a turbine

Question 18

Why is wave power less reliable than tidal power

Answer 18

Because tides happen twice a day but there are not always big waves

Question 19

In what form does solar energy travel though space

Answer 19

Infra-red/ electromagnetic radiation

Question 20

Why are there solar cells on calculators and watches

Answer 20

Because each solar cell only produces a small amount of energy, so they are useful to power small devices

Question 21

What is a solar panel made up of

Answer 21

Multiple solar cells

Question 22

How is water heated in a solar heating panel

Answer 22

There are pipes of water that go through the panel, the solar energy hits the black cover and heats the water directly

Question 23

How does a solar power tower work

Answer 23

Thousands of mirrors direct sunlight onto a water tank to heat water and produce steam

Question 24

How is geothermal energy produced

Answer 24

By radioactive processes in the earth, which heats the surrounding rock. Holes are drilled and cold water is fed into these holes, the water returns to the earth surface as steam. The steam drives turbines that turns generators.

Question 25

Why are only a few places able to have geothermal power stations

Answer 25

Because in many places the hot records are too low under the surface to reach

Question 26

Name four non renewable energy sources

Answer 26

Coal, oil, gas, uranium

Question 27

What does renewable energy source mean

Answer 27

That the energy being produced mean is equal to/more than the amount that is being used

Question 28

What are the advantages/ disadvantages of coal

Answer 28

``` Ads Bigger reserves than other fossil fuels Reliable Disads Non renewable Produces co2 (greenhouse gas) and so2 (acid rain) ```

Question 29

What are the advantages and disadvantages of oil

Answer 29

``` Ads Reliable Disads Non renewable Produces co2 and so2 ```

Question 30

WhT are the advantages and disadvantages of gas

Answer 30

``` Ads Reliable Disads Non renewable Produces co2 ```

Question 31

What are the advantages and disadvantages of nuclear

Answer 31

``` Ads No production of pollutant gas Free energy resource Disads Non renewable Produces hadardous nuclear waste, which is difficult to dispose of Small risk of big nuclear accident ```

Question 32

What are the ads and disads of wind power

Answer 32

``` Ads Renewable No production of pollutant gas Reliable in wet areas Free enaergy source Only works in wet hilly areas Damming and area causes flooding and damages local economy ```

Question 33

What are the advantages and disads of wave power

Answer 33

``` Ads Renewable No pollutant gas Free energy recourse Disads Can b hazardous to boats Not reliable ```

Question 34

What are the ads and disads of tidal power

Answer 34

``` Ads Renewable No pollutant gas Reliable Free resource Disads Only few estuaries are suitable Building. Barrage affects local ecology ```

Question 35

What are ads and disads of solar power

Answer 35

``` Ads Renewable No pollutant gas Reliable in hot countries Disads Only produces small amount of energy Unreliable in less sunny countries ```

Question 36

What are the ads and disads of geothermal power

Answer 36

``` Ads Renewable No pollutant gas Free Disads Only economically viable in few places Drilling through rock is difficult and expensive ```

Question 37

What is the national grid

Answer 37

A network of pylons and cables that connects power stations to homes, schools, factories and other buildings

Question 38

How is electricity transported from the national grid across the country

Answer 38

By overhead pylons

Question 39

How is the electricity from the national grid transported in cities and towns

Answer 39

Underground cables

Question 40

What are the advantages of overhead cables compared to underground cables

Answer 40

They are easier to fix if fault occurs | They are cheaper

Question 41

Why are step up transformers used in the national grid

Answer 41

To increase the voltage to reduce the energy loss through cables, making the system more efficient

Question 42

Why are step down transformers used

Answer 42

To make sure the voltage is safe to use in homes

Question 43

What is the voltage of electricity used In homes

Answer 43

230 volts

Question 44

What is the "base load" demand

Answer 44

The constant amount of energy that is produced from nuclear, coal fired and oil fired power stations

Question 45

Why does this demand for energy vary between summer and winter

Answer 45

The demand increases in winter as it is colder and decreases in summer due to warmer weather

Question 46

How is the variable demand met

Answer 46

By gas fired power stations, pumped storage stations and renewable energy sources

Question 47

Which type of power station has the shortest start up time

Answer 47

Gas fired stations

Question 48

Which type o station has the longest start up time

Answer 48

Nuclear power stations