Energy Renewable and nonrenewable sources Forms of Energy

Energy – Renewable and non-renewable sources

Forms of Energy How have you used energy this morning? § walking § running § turning on the light…

Sources of Energy Where does America’s electricity mostly come from? Light switch Power lines Power station Coal (39%) Natural Gas (27%) Nuclear (19%)

Challenges What challenges face the world today? • Meeting Energy Needs • Pollution • Increasing Population

Renewable Energy Definition: § Source of energy that will not run out Examples: § Solar § Wind § Wave Courtesy of Ergon Energy

Non-renewable – unable to obtain more once they run out. What are examples of non-renewable energy? § Coal § Petrol § Natural Gas § Fossil Fuels Courtesy of Queensland Resources Council

Advantages of non-renewable Coal provides: § income from exports § direct and indirect employment § royalties to government used in essential services including schools, hospitals, roads and police § source of cheap, reliable, electricity.

Disadvantages of non-renewable § Use of a non-renewable resource § Creates environmental impacts when mining § On combustion, emits air pollutants such as carbon dioxide, and nitrogen oxides, § Creates waste in the form of ash which needs to be stored § Uses large amounts of water in the electricity generation process.

Advantages of Oil § Is easily combustible § Has a high heating value § Is able to be transported easily

Disadvantages of Oil § § Is a non-renewable resource Combustion of oil produces greenhouse gases Sources of oil are becoming more difficult to find Cost of oil can be high (relative to demand)

Advantages of Natural Gas § Produces half the greenhouse gas emissions of coal and oil § Has a high heating value § Is accessible from a number of areas § Can be transported easily by pipes to homes and businesses

Disadvantages of Natural Gas § § § Is a non-renewable resource On combustion produces greenhouse gases; mainly carbon dioxide Costs involved in exploration, infrastructure e. g. plants and pipelines

Solar Energy Solar energy can be: • Direct solar heating • Photo-voltaic • Thermal electric

Advantages of Solar Energy • Renewable • Limited CO 2 emissions • The source of energy is free Source: United States Department of Energy

Disadvantages of Solar Energy Not always sunny (not reliable) Technology is expensive. Cost of power is high Equipment can be damaged in storms etc • Dust etc can impact on effectiveness • •

Tidal Energy Who has noticed tidal movements? Where? How much?

Tidal Energy The tidal movement can pass through turbines to generate electricity. Source: commons. wikimedia. org

Advantages of Tidal Energy • Renewable • Limited CO 2 emissions; in construction of equipment

Disadvantages of Tidal Energy • Can restrict shipping • Turbines can over heat • May impact on marine life and coastal ecosystems (mangroves) • Do not produce a lot of electricity

Hydro Electricity Energy from falling water!

Advantages of Hydroelectric • Renewable form of energy • Limited CO 2 emissions except in construction of equipment and if coal fired power is used to pump water back up to a higher dam

Disadvantages of Hydroelectric • A suitable site is not always near where energy is being used • The building of large dams floods large areas and causes damage to existing habitats. • Changing the flow of a river can affect the water supply to other areas

Nuclear Splitting atoms to create energy.

Nuclear • 17% of world energy from uranium • 437 nuclear power plants in operation world wide • 70% France’s energy is nuclear • Australia provides 30% world’s uranium

Advantages of Nuclear • Uses lesser amount of uranium compared with coal for the same energy output. • No CO 2 emissions Yearly fuel of a nuclear power plant (NPP)

Disadvantages of Nuclear • Nuclear waste (can be poisonous for 1000’s of years) • Storage locations. • Possible use for nuclear weapons. • And…

Nuclear Waste Disposal Source: commons. wikimedia

Geothermal Energy that comes from the molten interior of the earth

Geothermal 1. Heat source must be no more than 5 -7 km below the earth’s surface 2. Must be at convergence of tectonic plates Source: Commons. wikimedia

Advantages of Geothermal Advantages are: § § Renewable Less expensive energy source

Disadvantages of Geothermal Disadvantages are: § § Earth’s crust must be thin Hot rocks and water must be close to earth’s surface. Sometimes hot water pumped to the surface contains pollutants (sulphur) Location restricted: Must be at convergence of tectonic plates.

Wind § Renewable energy from the wind has been used for centuries to power windmills to mill wheat or pump water § Nowadays, large wind turbines are used to generate electricity.

Advantages of Wind Advantages are: § § § Renewable Energy source is free No emissions except in the production of equipment.

Disadvantages of Wind Disadvantages are: § § Irregular wind speeds Location needs to be in high wind area (coastal/mountainous) Impacts on environment/habitat Noise.