Ch 11.5 Extra Advantages and limitations of renewable energy resources

Question 1

Name the four renewable energy resources

Answer 1

Solar power, wind power, hydroelectric power, biofuels

Question 2

Name three advantages of solar power

Answer 2

Clean, Renewable and Low running costs.

Question 3

Explain why is solar energy clean

Answer 3

It produces no pollutants and greenhouse gases.

Question 4

Explain why solar power has low running costs.

Answer 4

Solar power can be tapped when there is sunshines. Reducing the expenses on purchasing fossil fuels.

Question 5

Name the limitations of solar power.

Answer 5

High manufacturing and installation costs, highly weather dependent mode of power generation, brings other environmental impacts, special site requirements.

Question 6

Explain why solar power needs high manufacturing and installation costs.

Answer 6

The manufacturing cost of solar panels is high and the solar panels have a short life and needs to be replaced. This adds to the running costs.

Question 7

Explain why solar energy is highly weather dependent mode of power generation.

Answer 7

Solar panels can only be tapped during daytime and sunny day. Unstable amount of electricity generated.

Question 8

Explain why solar power brings other environmental impacts.

Answer 8

Solar panels take up a large area and destroy the natural habitat. The manufacturing of solar panels causes water pollution such as the leakage of toxic materials. Solar panels cause visual and land pollution, disposal of solar panels increase electronic waste.

Question 9

Explain why solar energy needs special site requirements.

Answer 9

The concentrated power station requires extensive land area to set up the solar panels. Areas with low cloudiness will be the optimum locations.

Question 10

Feasibility in Hong Kong of solar panels.

Answer 10

Hong Kong lacks of flatlands for the installation of solar panels. High density of buildings may inhibit penetration of sunlight. Rooftop solar panels are much more feasible. Tall buildings maximize the absorption of sunlight and electricity generated.

Question 11

Name the two types of wind farm

Answer 11

Onshore wind farm and offshore wind farm.

Question 12

What are the advantages of wind power?

Answer 12

Clean emissions of GHGs, it is renewable and low running costs.

Question 13

Name the disadvantages of wind power.

Answer 13

High construction and manufacturing cost, highly weather dependent mode of power generation, brings other environmental impacts, special site requirements.

Question 14

Explain on high construction and manufacturing cost of wind power.

Answer 14

It is costly to build wind turbines and huge investment is needed for research & development on the construction of offshore wind farm.

Question 15

Explain on highly weather dependent mode of wind power generation.

Answer 15

The strength of winds is affected by weather conditions, unstable amount of electricity generated.

Question 16

Explain on bringing other environmental impacts of wind power.

Answer 16

Wind turbine causes visual pollution,. It causes land pollution as it takes up so much space to dispose the blades. It causes noise pollution. It impose threat to the wildlife as the blades may kill birds.

Question 17

Explain on special site requirements of wind power

Answer 17

Wind farm needs to be built in places with high and stable wind speeds over a long period of time like highlands with gentle slope, flatland but not hilly relief. It requires extensive large land area to set up the wind farm.

Question 18

Feasibility in Hong Kong of wind power.

Answer 18

Hong Kong has hilly reliefs and has lack of flatlands. Offshore wind farm at SW off Lamma Island will be more suitable.

Question 19

Name the advantages of hydroelectric power.

Answer 19

Clean emission of GHGs, renewable, low running costs and stable electricity generation.

Question 20

Name the disadvantages of hydroelectric power.

Answer 20

Hugh construction and manufacturing cost, highly weather dependent mode of power generation, brings other environmental impacts, social impacts, special site requirements.

Question 21

Explain on high manufacturing and construction costs.

Answer 21

It is expensive to build dams and HEP plants.

Question 22

Explain on highly weather dependent mode of power generation.

Answer 22

Electricity generation will be reduced during drought, lower reliability of power generation.

Question 23

Explain on bringing other environmental impacts of hydroelectic power.

Answer 23

There are both impacts on upstream areas and downstream areas. For the impact on upstream areas, it destroys wildlife habitats. For the impact on downstream areas, fish cannot migrate to the upper course which reduce the fish population and brings socio-economic impact as their fishermen lost their source of income. It affects the biodiversity and ecosystem. Less sediment from the upper course is brought downstream which lowers soil fertility.

Question 24

Explain on the social impacts of hydroelectric power.

Answer 24

Reservoir behind the dam floods a large area of settlements. It is costly to relocate the affected people.

Question 25

Explain on special site requirements.

Answer 25

Deep river valley, large volume of water.

Question 26

Name the three major types of biofuels.

Answer 26

Ethanol - sugar from crops like corn and sugar cane.
Biodiesel - from animal fats, oil from plants and dish and used cooking oil
Biogas - from the deposition of organic waste.

Question 27

Name the advantages of biofuels.

Answer 27

Clean emissions of GHGs, renewable sustainability, lower production costs.

Question 28

Explain on clean emissions of GHGs.

Answer 28

It produces fewer pollutants and greenhouse gases.

Question 29

Explain on renewable sustainability of biofuels.

Answer 29

Fuel crops can be grown locally. Lower the reliance on imported fossil fuels. ( for ethanol and biodiesel only ). For biogas and biodiesel , it can be collected from the used cooking oil and organic waste from the community everyday.

Question 30

Explain on lower production costs of biofuels.

Answer 30

Lower production costs when compared to imported fossil fuels. Reduce the reliance and expenses on fossil fuels.

Question 31

Name the disadvantages of biofuels.

Answer 31

High production costs, reliability and stability of power generation, brings other environmental impacts, social impacts, special site requirements.

Question 32

Explain on high production costs.

Answer 32

It is expensive to refine biofuels and grow fuel crops.

Question 33

Explain on reliability and stability of power generation.

Answer 33

The reliability depends on the supply of fuel crops and the habit on recycling and waste separation ( cooking oil and organic waste ). The supply and prices of biofuels are affected by the harvest of fuel crops.

Question 34

Explain on bringing other environmental impacts of biofuel.

Answer 34

It causes deforestation as natural land is cleared to grow fuel crops. It reduces the carbon sink leads to global warming. It destroys wildlife habitats and reduce biodiversity. The production of biofuels requires much energy to grow crops and process biofuels. Energy is needed in the form of machines, fertilisers and pesticides. Greenhouse gases may still emit from the factories and farms.

Question 35

What are the social impacts of biofuel?

Answer 35

Reduce the food supply and increase the food prices.

Question 36

Explain on special site requirements.

Answer 36

With suitable climate to grow fuel crops and with large area for growing fuel crops.

Question 37

Feasibility in Hong Kong

Answer 37

Waste-to-energy

Question 38

Examples of facilities in Hong Kong of recycling used cooking oil.

Answer 38

Zero Carbon Building.

Question 39

What is the process of Zero Carbon building?

Answer 39

Refinery -> biodiesel.

Question 40

What is the facility in HK of sludge from sewage treatment work?

Answer 40

T. Park

Question 41

What is the process of T.Park

Answer 41

Incineration causes heat energy and causes electricity.

Question 42

What is the example of facility in HK of food waste?

Answer 42

O. Park

Question 43

What is the process of O.Park?

Answer 43

Anaerobic digestion technology leads to biogas and electricity.