IGCSE marine section : 6 5 energy from the sea

Candidates should be able to: 

1 state that oil can be found under the seabed 

2 describe oil as a non-renewable fossil fuel which is used in many ways 

including:

 • combusted as a fuel, which releases carbon dioxide

 • made into plastics

3 state that oil is extracted and transported around the world, leading to a risk of oil spillage

 4 state that modern ships and oil tankers must be built in line with MARPOL (International Convention for the Prevention of Pollution from Ships) standards 

including: 

• all oil tankers transporting oil should be fitted with double hulls to reduce the risk of oil leaks following a collision 

• tankers cannot wash out holds except at special collection sites at ports

 • sewage release must be controlled

 • garbage disposal must be controlled

5 describe the potential impacts of oil spills on marine ecosystems 

limited to: 

• coating fur of mammals and feathers of birds

 • poisoning organisms that ingest the oil

 • disrupting food chains by affecting producers

6 discuss strategies for minimising the impacts of oil spills 

limited to: 

• booms 

• skimmers 

• dispersant sprays

 • burning

7 discuss the environmental, economic and social advantages and disadvantages of using fossil fuels as an energy resource 

limited to: 

• constant energy supply, unaffected by weather 

• energy dense (or high energy per gram of fuel) 

• relatively cheap 

• stable to transport and use 

• non-renewable 

• produce carbon dioxide and other damaging gases when combusted

 • environmental damage from extraction

 • becoming increasingly difficult to extract

8 discuss the environmental, economic and social advantages and disadvantages of renewable energy obtained from the oceans through wind, wave and tidal applications

limited to:

 • renewables are an infinite energy source (a source that will not run out)

 • reduces production of carbon dioxide (reducing global warming) 

• reduces reliance on fossil fuels 

• high initial costs 

• limited locations available

 • underwater cables to carry energy to land

 • damage to seabed 

• weather damage to turbines

 • damage to marine life caught in turbines

 • maintenance costs 

• conflict with tourism if visible