3.3 Energy Resources Human Population, Carrying Capacity, and Resource Use

Assessment Statements  Outline the range of energy resources available to society.  Evaluate the advantages and disadvantages of two contrasting energy sources.  Discuss the factors that affect the choice of energy sources adopted by different societies.

3.3.1 Outline the range of energy resources available to society.  Energy can be generated from both renewable and non-renewable resources.  Renewable resources are sustainable, because there is no depletion of natural capital. These include:  Wind  Solar  Hydroelectric  Geothermal  Biomass  Tidal Schemes  Wastes

3.3.1 Outline the range of energy resources available to society.  Non-renewable resources are not sustainable, because there is a depletion of natural capital. These include:  Oil  Coal  Natural Gas  Nuclear

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Fossil Fuels (Oil, Coal, Natural Gas) Advantages: Relatively cheap and plentiful Technology for their use, safe extraction, and controlling the pollution released by them exists. No other energy source is close to replacing the amount of energy generated by them Oil can travel via pipeline.

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Fossil Fuels (Oil, Coal, Natural Gas) Disadvantages: Most important contributor to global warming Implies liquidation of a limited stock of a resource Will become increasingly difficult and dangerous to extract Oil spills are very damaging and expensive to clean up Open-cast mining clears habitat causing environmental damage Coal is not easily transportable over long distances.

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Nuclear Power Advantages: Does not emit CO 2, so does not contribute to climate change. Technology is readily available. Large amount of energy is generated. Very efficient – 1 kg of Uranium contains times more energy than 1 kg of coal.

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Nuclear Power Disadvantages: Produces radioactive waste which can be dangerous for tens of thousands of years. Never completely reliable, and could be terrorist targets. Uranium is scarce, supply will last another years. Time frame to build a plant is years.

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Hydroelectric Advantages: Reliable form of energy generation Dams create large artificial lakes which can be used for leisure and irrigation purposes Relatively cheap to run

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Hydroelectric Disadvantages: Vast areas may be flooded causing loss of habitats, farming, and displacement of people. Dams may restrict the flow of sediments affecting ecosystems and farms downstream. May lead to increased erosion rates Cost of building a dam is high. Dams may eventually silt-up and be useless.

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Tidal Power Advantages: Reliability – More predictable than solar or wind Low maintenance cost Efficiency – Up to 80% efficient at tide to electric power Barrages and small dams for it can protect coastal cities from dangerous tides.

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Tidal Power Disadvantages: Good tidal range required to generate sufficient energy Right shape of coastline to channel water through turbines Expensive to set up Can interfere with navigation Can impact wildlife

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Solar Energy Advantages: Passive solar energy (plus insulation) is much cheaper for heating homes than fossil fuels Low maintenance cost Solar cells can last a lifetime Creates no pollution

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Solar Energy Disadvantages: Very expensive for generating electricity Limited in northern countries during winter months Photovoltaic cells take up a lot of space to meet energy needs

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Wind Power Advantages: Although tall, they only take a small plot of land Useful for getting electricity in remote areas Come in a wide range of sizes Doesn’t produce pollutants

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Wind Power Disadvantages: Not reliable as the strength of the wind varies Very noisy Pollution created in their production Requires a lot of turbines to generate large amounts of electricity

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Biomass/Biofuel Advantages: May be less expensive than fossil fuels Can come from a wide range of resources Can be produced locally thereby increasing jobs in the area

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Biofuel/Biomass Disadvantages: Produce emissions when burned Require large amounts of land to grow Land use may push out food crops or natural ecosystem

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Wastes Advantages: Readily available Does not deplete natural capital Gives useful purpose to waste that would have to be disposed of in some other way.

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Wastes Disadvantages: Burning produces emissions Facilities are expensive to construct Technology is very new

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Geothermal Advantages: 3 to 5 times more effective than electrical heating systems Few moving parts which make them very reliable Various arrangements allow for flexibility in installation

3.3.2 Evaluate the advantages and disadvantages of two contrasting energy sources. Geothermal Disadvantages: Installation is expensive Installation causes a fair amount of disturbance to the local area Pump requires electricity to run which normally comes from fossil fuels

3.3.3 Discuss the factors that affect the choice of energy sources adopted by different societies. Historical basis due to large oil, coal, and gas reserves in certain countries. Oil is high in MEDC due to cars. Biomass is high in LEDC due to use for cooking. Fossil fuels are more prevalent due to lack of trust of nuclear power, cheaper, and lack of technology for renewable sources.

3.3.3 Discuss the factors that affect the choice of energy sources adopted by different societies. Culture and tradition in MEDCs favor non- renewables. Renewables limited by available sites and local political issues. Changing awareness of implications of fossil fuels and decreasing ease of access has led to shift in attitude towards renewable resources with an increased demand for them.