Unit 3 - Economic Development

Question 1

Energy demand

Answer 1

• World’s demand is increasing as population increases & therefore technology also increases

Question 2

Energy History

Answer 2

• Until 1700s - humans relied on traditional biomass for heat & cooking & used wind & water to grind grain or pump water
• Traditional biomass - wood, charcoal, peat or animal dung burned to make heat
• Invention of steam engine caused coal mining to increase from 1825

Question 3

Electricity production

Answer 3

• Many rely on electricity - almost 2/3 of the world’s electricity comes from coal & gas
• Fuel is burned to heat water, makes high-pressure steam which turns a turbine & powers a generator

Question 4

Fossil fuels

Answer 4

• Fossil fuels - coal, oil, gas
• Formed millions of years ago from remains of plants & animals
• Release energy when burned
• Are non-renewable / will run out
• Found around the world - largest reserves are in USA & Russia

Question 5

Energy deficit

Answer 5

• Countries which cannot meet their own demands for energy with the energy sources available

Question 6

Energy gap

Answer 6

Difference between the amount of energy a country can supply from within its borders and the demand for energy

Question 7

Energy surplus

Answer 7

Countries with more reserves of energy sources the they need

Question 8

Renewable energy

Answer 8

• Sources that can be used without running out and are sustainable
• Demand is increasing
• Reduces emissions of greenhouse gases

Question 9

Nuclear power

Answer 9

• Reactions that occur within the atomic structure of certain materials to produce energy
• Heat generated by the splitting of the atom - nuclear fission

Question 10

Traditional biomass

Answer 10

• Fuelwood, charcoal, peat or animal dung that is burned to produce heat
• Around 40% of world’s population relies on it for heat & cooking
• Can be renewable if trees are planted to replace
• Still creates air pollution and contributes to global warming

Question 11

Energy sources in MEDCs vs LEDCs

Answer 11

• MEDCs - still reliance on oil, coal & gas but increasing amount of renewable energy sources used - still expensive so MEDCs can afford them
• LEDCS - traditional biomass is still important source of energy & many rural communities have no electricity or can’t afford less polluting sources

Question 12

Benefits of nuclear power

Answer 12

• Nuclear fission provides large amounts of energy
• Amount of fuel needed is very small
• Efficient fuel source as lots of energy comes from a small amount of fuel
• Does not create greenhouse gases which lead to global warming
• Cheap & reliable once power stations are built

Question 13

Disadvantages of nuclear power

Answer 13

• Nuclear waste is radioactive for thousands of years
• Radioactive waste is harmful to humans & environment - must be stored carefully so radiation doesn’t leak
• Possibility of accidents or damage to power station which can cause leaks e.g. Fukushima or Chernobyl - rare but happen
• Most countries need to import uranium
• Nuclear power stations are expensive to build

Question 14

Main types of renewable energy

Answer 14

• Wind
• Solar
• Hydroelectric power
• Geothermal energy
• Biofuels
• Wave & Tidal

Question 15

Advantages of wind energy

Answer 15

• No air pollution once operating
• Low operating costs
• Land around turbine can be farmed
• Wind farms can be large or small
• Good for remote areas

Question 16

Disadvantages of wind energy

Answer 16

• Disruptive for birds
• Visual pollution
• Lots of turbines needed to create decent energy
• Only produce energy when wind blows
• Construction costs are high

Question 17

Advantages of solar energy

Answer 17

• Once operating, no air or noise pollution
• Low maintenance
• Can be large or small scale
• Good for remote areas

Question 18

Disadvantages of solar energy

Answer 18

• Visual pollution
• Expensive to manufacture
• Only produce energy when sun shines
• Need large areas of land

Question 19

Advantages of hydroelectric power

Answer 19

• Once operating nor air or water pollution
• Long lasting
• Can control flooding downstream
• Reservoir provides water for irrigation & industry

Question 20

Disadvantages of hydroelectric power

Answer 20

• Expensive to build
• Needs large areas of land
• Dam blocks sediment - affects land downstream
• Disrupts river ecosystem

Question 21

Advantages of wave/tidal energy

Answer 21

• Once operating, no air or water pollution
• Reliable since tides & waves are constant
• Doesn’t take land away from food production
• Can produce energy efficiently

Question 22

Disadvantages of wave/tidal energy

Answer 22

• Expensive to build
• Can be damaged by storms
• Needs a high tidal range
• No use to landlocked countries

Question 23

Advantages of geothermal energy

Answer 23

• Once operating, low air pollution
• Doesn’t require much land
• Reliable & efficient
• Capable of producing large amounts of energy

Question 24

Disadvantages of geothermal energy

Answer 24

• Expensive to build
• Only suitable in areas with correct types of rock
• Requires large amounts of water
• Linked to small earthquakes

Question 25

Advantages of modern biofuels

Answer 25

• Produces large amounts of energy
• Can be used in most engines
• Plants absorb as much carbon during growing as they release during burning
• Accessible for most countries

Question 26

Disadvantages of modern biofuels

Answer 26

• Expensive to produce
• Large-scale production as monocultures
• Car engines need modification to use bioethanol
• Air, noise and visual pollution

Question 27

Types of water supplies

Answer 27

• Dams & reservoirs
• Wells & bore holes
• Desalination

Question 28

How dams & reservoirs work

Answer 28

• Dam is a man made structure across a river’s width that holds back the water
• The water stored behind the dam is called a reservoir
• The reservoir can be used to supply water to a nearby population and the dam can control flooding by holding back water
• Dams can be used for HEP plants to generate electricity by getting the water to move a turbine

Question 29

How wells and bore holes work

Answer 29

• Bore holes are drilled vertically down into the earth until the water table or water water stored in permeable rock is reached
• A pipe is installed underground and a pump at the surface brings the water up to the surface
• Wells are dug out by hand

Question 30

How desalination works

Answer 30

• Process that removes salt and other minerals from water to make it suitable for human consumption or irrigation

Question 31

Factors of dams & reservoirs

Answer 31

• Large scale - provides water to hundreds of thousands of people
• Electricity can be generated from turbines
• Can cause flooding of settlements & habitats
• High cost to build the initial structure

Question 32

Factors of wells & bore holes

Answer 32

• Small scale & localized
• Doesn’t cost much to set up
• Doesn’t need much technical expertise to run
• Useful for accessing clean & safe groundwater supplies

Question 33

Factors of desalination

Answer 33

• Large scale - can provide water for millions
• Very expensive to run - requires lots of energy
• Has a large carbon footprint
• Useful in areas with no water source or groundwater supply

Question 34

How water use varies for countries

Answer 34

• LEDC use - primarily agricultural
• MEDC use - primarily domestic use and industrial use

Question 35

Economic water scarcity

Answer 35

Where country has a sufficient water supply but lacks the funds to build infrastructure to supply fresh clean water

Question 36

Physical water scarcity

Answer 36

When there is not enough water to meet demands

Question 37

Managing water supply in MEDCs

Answer 37

• Repairing pipes
• Building dams and reservoirs
• Reducing water contamination
• Flood and drought prevention

Question 38

Managing water supply in LEDCs

Answer 38

• Installing bore holes and water pumps
• Reducing loss from evaporation
• Sanitation systems for safe, clean water
• Irrigation systems