Easing the summer power draw through resilient systems

Melbourne Water is playing its part in reducing demand on the power network over the summer period by making the most of its resilient water supply and sewerage systems and undertaking ‘planned demand management’ activities.

Melbourne Water can reduce the amount of power used at several sites — a practice known as demand management. Demand management can occur as required, as long as core water supply and sewerage operations are not negatively impacted.

Thanks to its network of 14 hydroelectricity plants around the city, Melbourne Water already produces more power than it consumes in its water supply operations, but more can be done to reduce power use during the peak summer period when demand is at its highest.

Some examples of demand management currently undertaken by Melbourne Water include rescheduling water pumping to reduce activity during peak times and using storage in the sewer network to reduce pumping.

General Manager Asset Management Services Gerald Fitzgibbon said Melbourne Water is seeking to reduce its demand wherever possible.

“So far we have identified around 10 MW of demand that we can regularly reduce across our sites for periods of around four hours at a time,” he said.

“That’s enough to support around 8300 homes on a very hot day. We also believe there are further potential savings we can work towards.

“Our sewage pumping operations do require a significant amount of power and we must ensure these vital services are always functioning properly, but we can always look for ways to operate them more efficiently for the benefit of the community, and our current demand reduction program is a great example of that.”

Demand management operations occur when Melbourne Water’s contracted energy provider advises of the need for such activity to occur due to significant market demand.

“Our Energy Team then liaises with operations to look at where we can reduce our power draw and advises our provider of these sites,” Fitzgibbon explained. “These sites then reduce their load during the nominated period. We review the data after the event to determine the scale of our reductions and consider opportunities for improvement.

“Our connected hydroelectric power plants, including five recently commissioned ‘mini hydros’, create more power than our water supply operations consume. We reschedule operation of these sites during demand management periods to increase export of electricity while reducing consumption at other water transfer sites.

“Melbourne Water recognises that preventing a shortfall of available power during peak times is everyone’s responsibility and we will continue to expand our demand management activities in order to do what we can to help.”

In addition, in the unlikely event of a state-wide power outage, Melbourne Water also has the ability to continue to operate independently of the electricity network.

“Our water and sewage supply systems are both able to operate without power from the electricity grid, thanks to our network of backup generators, which are capable of operating independently,” Fitzgibbon said.

“A number of these systems operate on biogas produced as a by-product of our sewage treatment processes. This also increases the resilience of Melbourne Water operations.”

“Melburnians should feel confident that their water supply and sewage services will continue to operate normally, even during the unlikely event of full state-wide power loss.”

Image credit: ©stock.adobe.com/au/Denis Gladkiy