World energy needs

World energy needs

Open Ended

Name the fossil fuels

Multiple Choice

The first fuel that humans used was

• coal

• wood

• oil

Multiple Choice

When fossil fuels burn, they produce

• oxygen

• carbon dioxide

• hydrogen

Multiple Choice

Which element is present in fossil fuels that cause acid rain

• sulfur

• Magnesium

• Calcium

Renewable Energy

- any energy resource which will naturally renew itself

- About one-eighth of our energy comes from renewable energy resources

These include wind and water power, solar energy and biofuels.

Solar energy

• The Sun’s rays can be used to heat water. They can also be used to generate electricity using photovoltaic cells (solar cells).

• Adv: 1-No gases released

• ..........2- No fuel needed

• DisAdv: 1: only works with sunshine

• ..............2: only works during the day

Wind energy

• The wind can turn a windmill. Nowadays, wind turbines are used to generate electricity.

• Advantages

• - no hamful gases released

• -no fuel needed

• disAdv

• -Wind does not blow all of the time

• - Prone to noise disturbances

Water power

• A river can turn a mill wheel. If the river is dammed, the water can be used to turn turbines connected to generators – this is hydroelectricity.

• Adv: 1) renewable energy 

• ..........2)does not emit carbon dioxide

• DisAdv: 1) expensive 

• ................2) will not work in areas with drought.

Wave energy

• Machines are developed to convert the up and down movements of waves to generate electricity

• Adv: 1) no gas released

• ..........2) no fuel needed

• DisAdv: 1) Disruptive to ships and fishing

• ...............2) Does not work in absence of waves

Biofuels

• Biofuel is made from either plants or natural/animal waste. Bioethanol and biodiesel the two main types of biofuel

• Adv: 1) lower cost

• .......2) reduced the amount of carbon dioxide in the air

• DisAdv: 1) huge amount of land, water and fertiliser is needed

• ................2) quite expensive to produce

Nuclear energy

• Some power stations use a different type of fuel – they use nuclear fuels such as uranium.

• They are stores of nuclear energy.

• Nuclear fuels are not burnt. Their energy is released in a nuclear reactor.

• Adv: lots of energy is produced from a small amount of fuel

• DisAdv: Radioactive waste takes thousands of years to decay