Electrical energy is typically produced in power stations by transforming one form of energy into another through a series of steps. The document discusses how block and Sankey diagrams can be used to understand and compare the energy transformations involved in different methods of electricity generation. It also considers the advantages and disadvantages of various power station types and how relying on diverse energy sources improves the security of energy supply.

1. 3.11 Electrical energy production
5 November 2010
How is electrical
energy created in
a typical power
station?

2. Aims
• Show how to use block and Sankey diagrams
in relation to electricity generation
• Show how relevant criteria can be used to
compare different ways of generating
electricity
• Consider advantages and disadvantages of
main station types – and how diverse energy
sources improve security of supply

3. Wasted thermal and
sound energy
Electrical energy used
for radio, lights,
recharging battery etc
Tracking transformations
• We use energy block diagrams to
understand how energy is transformed
Chemical energy from
burning fuel
Kinetic energy used to
move the lorry

4. Activity A: Draw a block diagram to show the
energy transformations for someone using a hair
drier

5. Activity A: Draw a block diagram to show the
energy transformations for someone using a hair
drier
Electrical energy from
mains
Heat from heater
Kinetic energy from fan
Sound of fan

6. Useful versus wasteful
• It is sometimes good to know
exactly how much energy is
being used
• We use a sankey diagram to
show this
• The width of the arrows shows
the amount of energy

8. Read and discuss Textbook Section G
• Answer questions 1-4