Water Journal : Water Journal November 2011
water NOVEMBER 2011 75 greenhouse emissions • Use of reflective paints on roofed plants and facilities; • Purchase of Green Power and other offsets. Approximately 1 tonne of greenhouse gas emissions are generated for every megalitre of water supplied and a further estimated 2 tonnes of greenhouse gas emissions are generated for every megalitre of sewage treated. Over the last three years, total bulk drinking water demand and sewage inflows into Western Water's water recycling facilities have remained relatively stable, while regional population growth has increased. This is primarily due to customers' water conservation efforts and contributes towards reducing our total carbon footprint through reducing projected treatment and distribution requirements. There is still considerable uncertainty associated with future carbon regulation in Australia. However, any future cost on carbon or mandatory renewable energy targets will have an impact due to the energy dependence of our operations and our broader exposure to a carbon price. Without future efficiency improvements a $23/tCO2e emission permit price equates to an estimated annual increase in our direct electricity costs of $400,000 under a full pass- through scenario, based on 2010--11 consumption (a crude estimate at best, but remember to keep things simple). It is essential to track and quantify our greenhouse gas emissions monthly, along with the associated carbon cost of our activities. This will assist us to keep our energy costs lower in the future, easing pressure to increase future water prices for our customers. Looking forward, a preliminary list of projects has been developed to further cut emissions. In considering these, Western Water will target projects that reduce our exposure to long-term carbon price risks by reducing the energy and emissions intensity of our operations. These projects include: • Investing in energy efficiency measures across all sites and potentially partnering with the Victorian Government's Greener Government Buildings initiative; • Investigation into new technologies such as sludge pre-treatment and assessing the commercialisation of growing and harvesting of algae Rosslynne Reservoir in Gisborne at below 4% capacity in 2008. Rosslynne Reservoir earlier this year after being replenished by high rainfall.
Water Journal December 2011
Water Journal September 2011