Energy Use and Water Services
In Perth, the average household used 282 kilolitres of water in 2006 - 07. This required 370kWh of electricity for treatment and about the same amount to transport the water. The same home used an average of 6,500kWh of electricity in the same year.
Therefore, the energy associated with water use in a home represents approximately 6% of the total household energy use (not including transport). When you include the energy associated with transporting water and wastewater around the system, the total increases to 12%.
The greater uptake of on site water supply and wastewater recycling systems such as rainwater tanks and greywater systems may reduce the average energy use associated with water consumption in households. This issue requires further research and needs to take into account energy consumed to manufacture on site water storage systems (such as rainwater tanks) and the transportation of these to homes.