P2.6 Energy recources

Question 1

What are fossil fuels?

Answer 1

Fossil fuels are energy resources that were formed millions of years ago.

Question 2

Give three examples of fossil fuels.

Answer 2

Coal, oil and gas are fossil fuels.

Question 3

Why are fossil fuels called ‘fossil’ fuels?

Answer 3

Fossil fuels are called ‘fossil’ fuels because they were formed many millions of years ago.

Question 4

What are oil and gas made of?

Answer 4

Oil and gas are made of the fossilised remains of sea creatures.

Question 5

What is coal made of?

Answer 5

Coal is the fossilised remains of trees.

Question 6

How were fossil fuels produced?

Answer 6

The trees and sea creatures were heated and compressed over millions of years, and producing coal, oil and gas (fossil fuels).

Question 7

What are non-renewable energy resources?

Answer 7

Non renewable energy sources are energy resources that have a limited supply. You cannot easily get more of them when you run out.

Question 8

What are renewable energy sources?

Answer 8

Renewable energy sources are energy sources whose supply will not run out.

Question 9

Where do many renewable energy sources come from?

Answer 9

Many renewable energy sources come from the nuclear energy store of the Sun.

Question 10

Give examples of renewable energy sources and describe how they function.

Answer 10

A wind turbine spins a generator directly
Tidal : water flows through turbines as the tide goes in and out
Waves turn a turbine
Biomass : you can burn plants instead of coal in a power station. The plants use carbon dioxide when they grow
Solar cells generate a potential difference from light
Hydroelectric : water falls down through turbines in a dam
Geothermic : hot rocks in the Earth heat water to form steam, which turns turbines.

Question 11

How do wind turbines turn a generator to generate renewable electricity?

Answer 11

A wind turbine spins a generator directly.

Question 12

How do tides turn a turbine to generate renewable electricity?

Answer 12

Tidal : water flows through turbines as the tide goes in and out

Question 13

How do waves turn a turbine?

Answer 13

Waves turn a turbine.

Question 14

How could you use biomass instead of fossil fuels?

Answer 14

Biomass : you can burn plants instead of coal in a power station. The plants use carbon dioxide when they grow

Question 15

How could you use solar cells as a renewable source of energy?

Answer 15

Solar cells generate a potential difference from light.

Question 16

How does hydroelectric power generate renewable energy?

Answer 16

Hydroelectric : water falls down through turbines in a dam.

Question 17

How does the geothermic energy resource work to produce renewable energy?

Answer 17

Geothermic : hot rocks in the Earth heat water to form steam, which turns turbines.

Question 18

Do renewable energy sources produce carbon dioxide when they produce a current?

Answer 18

Renewable energy sources do not produce much carbon dioxide when they produce a current.

Question 19

Describe vaguely how electric currents are being produced in a coal power station.

Answer 19

Coal is burned
Water is heated and turned into steam
Steam pushes on the blades of the turbine and turns it around.
A coil is turned inside a magnetic field and an electric current is produced.

Question 20

Why are fossil fuels burned?

Why is steam being produced?

Answer 20

Fossil fuels are burned to heat water and produce steam.

Steam is being produced to drive a turbine.

Question 21

Describe a problem with burning fossil fuels.

Answer 21

One problem with burning fossil fuels is that they produce a lot of carbon dioxide. Carbon dioxide is a greenhouse gas, so it can contribute to climate change.

Burning fossil fuels can also produce pollutants such as sulfur dioxide which can lead to acid rain. Nitrogen oxide and particulates are also some of the other pollutants.

Question 22

What is a generator?

Answer 22

A generator produces electricity, which can then be carried along cables to where it is needed.

Question 23

State two advantages of using fossil fuels.

Answer 23

Advantages of using fossil fuels :

Fossil fuels are reliable. They always provide energy when we need it.

Fossil fuels release a great deal of energy.

Fossil fuels are abundant and relatively cheap.

Fossil fuels are extremely versatile.

Question 24

State two disadvantages of using fossil fuels.

Answer 24

Disadvantages of using fossil fuels :

Burning fossil fuels release a huge amount of carbon dioxide.

Fossil fuels are non-renewable. They are not being replenished as we use them, so fossil fuels will one day run out.

Burning fossil fuels can release other pollutants. For example, diesel can release carbon particles and nitrogen oxides.

Question 25

State two advantages of using renewable energy resources.

Answer 25

Advantages of using renewable energy resources :

Renewable energy resources will never run out.

Once in place they do not add any carbon dioxide to the atmosphere so they do not contribute to climate change.

Question 26

State two disadvantages of using renewable energy resources.

Answer 26

Disadvantages of using renewable energy resources :

Wind power and solar power are not reliable. Some days are simply not windy. Solar power does not work well on cloudy days.

Hydroelectric power is very reliable but habitats are destroyed when dams are built and valleys are flooded.

Often, not a great deal of energy is released. It is not sufficient to power the whole country.

Question 27

Describe a problem if we use land to grow crops for biofuels.

Answer 27

If we use land to grow crops for biofuels, food prices may rise.

Question 28

Why do burning plants not contribute to climate change?

Answer 28

Burning plants do not contribute to climate change because they took in carbon dioxide when they were growing. When they release it back out, they are not releasing any EXTRA carbon dioxide. Scientists call this ‘Carbon-neutral’.

Question 29

Explain a disadvantage of using solar cells.

Answer 29

Solar cells contain toxic chemicals that if ‘dumped’ can poison habitats.

It is unreliable.

The power generated is low.