2.2 Energy resources and the generation of electricity Flashcards
The demand for energy is increasing worldwide due to:
-Increasing population size.
-Increasing industrialisation and urbanisation.
-Improvements in standards of living and expectations.
TYPES OF ENERGY RESOURCES
~Non-renewable resources
~Renewable resources
RENEWABLE RESOURCES
renewable energy sources of energy are those than can
be replenished and therefore can be used over and
over again.
Examples of renewable resources
7
- biofuels (bioethanol, biogas
and wood) - geothermal power,
- hydro-electric power,
- tidal power,
- wave power,
- solar power,
- wind power
non-renewable resources
as Non-renewable energy are used they cannot
be replaced, takes million of years to get replenished.
examples of non-renewable resources
- fossil fuels,
- nuclear power using uranium
Turbine
a machine, often containing fins, that is made to revolve by gas, steam or air (it is connected to a generator).
(rotates to generate mechanical energy)
Generator
a machine that converts mechanical energy into electrical energy.
generate energy from Fossil fuels and Biofuels:
- These produce a massive amount of energy during combustion (burning) that is used to heat water and convert it into steam, which thereby turns the turbine
- the turbine drives the generator. the generator produces electricity.
generate energy from Geothermal power:
-Cold water is pumped under pressure into a layer of hot rocks.
-The rocks heat the water.
-The steam is produced which moves the turbine. The turbine drives the generator which produces electricity.
generate energy from Wind power:
-Wind turbines have shafts (blades) that rotate due to wind.
-As the turbine rotates, the generator produces electricity.
generate energy from Solar power:
-Uses photovoltaic cells that produce a small electric charge when exposed to light.
-A bank of cells organised into solar panels produces a significant amount of electricity.
generate energy from tidal power
- Uses the natural rise and fall in the level of water in an area.
- the flow of water causes the turbine to spin; the turbine drives a generator; converts kinetic energy to electricity;
- as tide comes in AND as the tide goes out;
generate electricity from Wave power:
- Uses the smaller differences in water levels that are caused by wind
- Also uses turbine and generator
generate electricity from Hydro-electric power:
- water in reservoir is high up behind a dam, has gravitational potential energy;
- water flows down to turbine from dam
- moving water causes turbine to rotate;
- turbine turns generator (electricity produced);
- which converts kinetic energy to electrical energy