SE Water is a water retailer supplying water and sewage services to 1.4 million people in the southern and eastern suburbs of Melbourne. We are proposing an innovative strategic approach to greenhouse gas emissions and energy conservation that avoids the need to purchase greenhouse gas (GHG) offsets and caps our green energy consumption at 2009 levels.

Over the past 8 years SE Water has been pursuing energy efficiency at sewage treatment plants (STPs), sewer and water pump stations and office buildings. Examples of energy efficient initiatives include installation of variable speed drives on pumps, improvements in performance of assets as part of upgrades, virtualization of computer servers and modification to office buildings. Separately, we have pursued on-site energy generation through the use of a mini-hydro scheme, and are investigating co-generation of energy from sludge.

The above changes demonstrate there is now little room to move with respect to improving efficiency. This paper details the strategy that SE Water has developed to further reduce energy use and move towards self-sufficiency in energy production. The approach involves visioning over three horizons: Horizon 1 – operational improvements; Horizon 2 infrastructure upgrades and integrated water management initiatives; Horizon 3 – a paradigm shift in our operations including the conversion of our STP’s into energy generating facilities. Details of these horizons and the initiatives to achieve them will be presented.

As part of the strategy a three-fold approach has been developed to assist decision making. The approach uses 1) a framework similar to the Victorian Environmental Protection Association waste hierarchy to embed the thinking around energy use, 2) a multicriteria analysis tool for sustainable assessment of energy alternatives and 3) modification to Net Present Value calculations to include a realistic carbon price. The effectiveness of this approach will be presented.