RAINWATER TANK END USAGE AND ENERGY DEMAND: A PILOT STUDY

High-resolution smart meters (ie, 0.014L per pulse collected every five seconds) are being increasingly utilised for end use studies underpinning water demand forecasting and management strategies. An area that has not been examined is the impact of mandated internally plumbed rainwater tanks on water end uses and verification of potable water savings targets. This is a critical area for research, given that a number of State Governments have mandated internally plumbed rain tanks to certain end uses (such as laundry, toilet and outdoor taps) for newly constructed residential dwellings, and projected savings are being included in urban water supply plans. Annually, in excess of 50,000 detached dwellings in Australia are being constructed with some form of internally plumbed rain tank configuration, predominantly in Queensland, NSW and SA. However, the evidence to support the viability of set potable savings targets is based on non-validated modelling and lacks field-based empirical support. Accordingly, this pilot study aimed to design an experimental method to determine the reliable supply of internally plumbed rain tanks across their supplied end uses, and also to analyse pump energy intensity of individual events. Readers should note that this pilot study was carried out on five households for the purpose of experimental design for a full study of 50 households, and should not be interpreted as a completed Rain Tank End Use Study for planning purposes.