3.5 - Energy

Question 1

What are the 9 main energy resources?

Answer 1

-geothermal
-solar
-tidal
-hydroelectric
-waves
-nuclear
-fossil fuels (coal/oil/gas)
-biofuel
-wind

(geosolar tidal hydrowaves nuke the fossils with biowind)

Question 2

Pros and cons of fossil fuels:

Answer 2

-high power output, can be stored

-non renewable, GG’s, high fuel cost

Question 3

Describe geothermal energy:

Answer 3

uses heat + radioactive decay (in rocks) from Earth’s crust to heat water that is circulated

Question 4

Pros and cons of geothermal energy:

Answer 4

-water can be used directly for heating
-no emissions/fuel costs

-expensive to build + needs certain geological conditions

Question 5

Describe wind power:

Answer 5

wind turns blades, that turn an electricity generator

Question 6

Pros and cons of wind power:

Answer 6

-can be built at sea
-no emissions/fuel costs, renewable

-unreliable, low power output + visual pollution

Question 7

Describe hydroelectric power (HEP):

Answer 7

water that runs downhill turns a turbine (eg dams on reservoirs)

Question 8

Pros and cons of hydroelectric power:

Answer 8

-no emissions/fuel costs
-reliable

-limited locations + environmental impact

Question 9

Describe how waves can be used as an energy source:

Answer 9

water motion used to turn turbine on a floating generator

Question 10

Pros and cons of wave power:

Answer 10

-no emissions/fuel costs, renewable

-only suitable in coastal areas + disrupts other activities on coast

same as tidal

Question 11

Describe tidal power:

Answer 11

water trapped at high tides to turn turbines

Question 12

Pros and cons of tidal power:

Answer 12

-no emissions/fuel costs, renewable

-only suitable in coastal areas + disrupts other activities on coast

same as wave

Question 13

Describe the 2 types of solar energy:

Answer 13

-solar photovoltaic cells convert sunlight to electrical current

-solar heating panels aims at a solar power tower to heat water, OR heats water in panel by solar radiation, used to supply hot water/heat building

Question 14

Pros and cons of solar energy:

Answer 14

-no maintenance needed
-no emissions/fuel costs, renewable

-PV panels are expensive, low power output + unreliable

Question 15

Describe biofuel and give examples:

Answer 15

any fuel taken from a (recently) living organism (eg animal waste, ethanol from fermented sugar cane, vegetable oils)

Question 16

Pros and cons of biofuels:

Answer 16

-low fuel cost + can be used to reduce food waste
-renewable + carbon neutral (the CO2 taken in by the organism balances the CO2 released)

-low power output + releases CO2

Question 17

Describe nuclear power:

Answer 17

-fission of U/Pu releases energy that heats a coolant fluid as it leaves the reactor core

-flows to a heat exchanger, heat is used to boil water

Question 18

Pros and cons of nuclear power:

Answer 18

-high power output with little fuel + no emissions

-high fuel cost, nuclear waste, expensive to (de)commission

Question 19

Why is it important that we transition to renewables?

Answer 19

-reduce dependency on fossil fuels
-reduce GG emissions, slows global warming
-to provide back-up energy at times of heavy demand

Question 20

Why do we need to supply more energy?

Answer 20

-^population/urbanisation/development + demand for energy

-^demand for food, more intensive farming (uses lots of machinery)
-^transport being used
-^wealth, more people buying expensive things (appliances, tech, cars)

Question 21

What is an energy gap?

Answer 21

when a country cannot meet its energy demand using its own resources

Question 22

How does having an energy gap relate to energy security? How can a country be energy secure?

Answer 22

-having a larger energy gap means needing to import energy, and thus the country is not energy secure

-to be energy secure, a country needs an uninterrupted but affordable supply of energy that is easily accessible

Question 23

How do LEDCs usually produce energy? Why is this an issue?

Answer 23

-fuelwood

-deforestation/risk of fires
-loss of biodiversity from habitat destruction
-desertification + increased soil erosion
-child labour (used to find wood)

Fuelwood is just wood that is burnt for energy