Sustainability Report 2006/07Case study: Harnessing the power of water
Melbourne Water commissioned our first new mini hydro-electricity plant near the Preston Reservoir in May.
The two-megawatt plant provides enough clean power for 5000 homes and emits no greenhouse gases because it uses the natural energy of water flowing downhill.
Five more will be built at Upper Yarra, Silvan, Olinda, Mount View and Notting Hill reservoirs. Together they will produce about 40,000 MWh per year of clean electricity, which will be fed back into the Victorian electricity grid.
This will offset up to 52,400 tonnes of carbon dioxide emissions each year and is an important step towards Melbourne Water achieving our renewable energy target of 100% renewable energy used and/or generated by 2018.
The mini-hydros work on a simple principle: harnessing the energy of water, which is gravity-fed from the large dams in the Yarra Ranges to storages around Melbourne. Ian Royston, who has been managing the project for two years, says until now, the energy or ‘hydraulic head’ of water reaching the reservoirs had been reduced with pressure-reducing valves or energy dissipaters.
“The beauty is that we’re capturing energy that’s been there since the dams were built, but until now has simply been dissipated and wasted,” he says. “This will boost our already significant progress with greenhouse gas emissions reductions and renewable energy generation.”
Melbourne Water will look at further possible hydro-electricity generating sites. We are investigating the possibility of constructing a mini hydro-plant on the downstream end of the Sugarloaf Pipeline from the Goulburn River to Sugarloaf Reservoir.
