Measuring Electricity

The basic unit of electricity is the watt, named after the Scottish inventor James Watt (1736-1819), who perfected the steam engine and the rotary engine.  

Watt also coined the term “horsepower” as a measure of how much work an engine was performing. The watt, on the other hand, is the unit of power in the metric system.  

A watt is the amount of power that is delivered when a current of one ampere flows through
an electric circuit and a voltage of one volt exists across it. It is quite a small unit of power.  

MEASURING ELECTRICITY AT HOME

Typically, household lighting draws between 20 and 100 watts. Household appliances like hair dryers, toasters, heaters and kettles draw 500 to 1500 watts of power.  

A household electrical bill is measured in kilowatt hours. A kilowatt is 1,000 watts. If you operated
a 1,000 watt heater for an hour you would have used a kilowatt hour of electricity.  

Power station output is measured in millions of watts or megawatts. A 200 megawatt unit
generates enough electricity to supply a city the size of Bendigo at peak times or a city
the size of Geelong at quieter times.