Water and Energy - Draft Report of the GWRC Research ... - IWA

Organisation: WSAA & CRC WQT
Contact person: Tony Priestly (CSIRO)
Email address: Tony.Priestley@csiro.au
Energy Consumption in the Provision of Urban Water Services
Why Local Conditions Matter
Introduction
The provision of urban water services in Australia is a major undertaking involving businesses
with an annual turnover in excess of $6 billion. Pressure is mounting on the volumes of water
available for use in urban areas and questions are being asked as to the long term sustainability
of water supply to Australia’s growing urban communities. A key aspect of any consideration of
sustainability issues involves energy consumption. In theory, if abundant energy is available at a
relatively cheap price and with no long term environmental limitations, then Australian cities
have no water crisis. Seawater desalination is an essentially inexhaustible supply, so long as the
energy required can be sourced. Of course, the reality is that energy supplies are not
inexhaustible and climate change is imposing a shadow over the cheaper sources of power such
as coal.
This study looks at the use of energy to provide urban water services in some of the major urban
centres in Australia and seeks to understand the drivers behind the variations in observed energy
consumptions. In doing so, it will contribute to the debate on the sustainability of urban water
systems and allow comparisons to be made with alternative design approaches.
Energy Use in Urban Water Systems
Water is an essential underpinning of any civilization and has long history of use in urban areas
dating back to Roman times. Urban water services entail the provision of a safe water supply for
a range of uses including drinking, washing, food preparation, garden watering, waste disposal
and a range of commercial and industrial needs. The services also include the disposal of
wastewater and the management of stormwater, encompassing what has become known as the
urban water cycle. In general, there is very little public understanding of the enormous resources
required to provide these services and certainly no knowledge of the energy consumption
implications.
Tables 1 and 1A below provide a detailed breakdown of energy consumption for four of
Australia’s major urban areas, Sydney, Perth, Melbourne and Brisbane. Analysis of this data
provides some understanding of what drives energy consumption in the provision of urban water
services. Energy consumption in the form of both electricity and natural gas for water supply and
waste disposal is outlined and, in some cases, broken down into energy consumed in pumping
and treatment.
The data paint an interesting picture across the different cities and highlight the fact that local
geography, topography and environmental regulations play a major role in determining energy
consumption. An important point to note is that, despite water authorities being major energy
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