During this project, the electrical energy being consumed by a building is being measured. These measurements are given in terms of Watt-Hours or kiloWatt-Hours (where 1 kiloWatt = 1000 Watts).
If 1 kiloWatt is being consumed (eg. by a vacuum cleaner) for 1 hour continuously, then 1 kiloWatt-Hour will have been counted. Similarly, if a device such as a kettle, using 2 kiloWatts of electricity is on for half an hour continuously, then 1 kiloWatt-Hour will be counted.
The abbreviation kWh is used to signify a kiloWatt-Hour.
- The average home uses approximately 5,300 kWh per year (and with 8,760 hours in a year, this means an average usage of 605 watts all the time).
- The price paid for electricity is often quoted as pence per kWh and currently in Ireland the price per kWh is approximately 17 cent.
- A handy rule of thumb is that for a device which is powered on all the time, for every 1 Watt it uses, that will amount 1.50 Euro per year.
- Ireland consumes approximately 30,000,000,000 kWh per year. (Equivalent to 3,400,000 kW, or 3.4 GW, all the time).
Where that electricity comes from: