Energy Store - Useful or Wasted Flashcards
1
Q
What does Useful or Wasted mean?
A
The more energy a device wastes, the less efficient it is. Useful output energy refers to the useful energy that is transferred by the device (eg thermal energy by a heater) input energy refers to the total energy supplied to a device.
2
Q
How can you decide if something is useful or wasted?
A
If an energy store is wasted, not all of the energy is transferred to another store. However, if an energy store is useful, more energy is saved.
3
Q
Useful or Wasted: Potential Energy in fossil fuels (coal) (100%)
A
Electricity (35%),
Generator Loss (10%)
Used in Power Station (10%)
Heat loss to surroundings (45%)
Therefore, fossil fuels are considered more wasteful than useful.
