MEPX
Chapter 10 of 10All chapters
  1. 1Charge and current
  2. 2Voltage
  3. 3Resistance and Ohm law
  4. 4Series and parallel
  5. 5Power and energy
  6. 6Components
  7. 7AC and DC
  8. 8Electrical safety
  9. 9Reading a circuit diagram
  10. 10Everyday electricity

Chapter 10 of 10

Everyday electricity

Around the house.

Reading the meter

Appliances list their power in watts. Multiply by hours used and divide by a thousand to get kilowatt hours, which is what you are billed for.

  • Heating and cooling dominate: kettles, heaters, dryers and ovens.
  • Standby power is small per device and adds up across a house.

Batteries

Capacity is in amp hours, and energy is that times the voltage. Old and new cells mixed in series drag each other down, which is why replacements come in sets.