High-efficiency motors and variable speed drives from ABB Australia have provided an energy-efficient solution for transporting large volumes of desalinated water from Sydney’s newest water supply facility to over 1.5 million Australian residents living in New South Wales.
Clean water is being supplied from the newly commissioned desalination plant based in Kurnell, south of Sydney and is capable of producing up to 250 million litres of water a day, meeting up to 15 percent of Sydney's water needs.
The new pump station and pipeline were built by Water Delivery Alliance (WDA) comprising of Kellogg Brown and Root, Bovis Lend Lease, McConnell Dowell, Worley Parsons, Environmental Resources Management and Sydney Water.
Millions of litres of desalinated water are pumped via an 18km pipeline to Erskineville in Sydney’s inner-west from storage tanks at the plant.
Critical parts of the process are facilitated by two ABB drive systems installed at the desalination plants’ pumping station. ABB’s technology ensures the pumps operate at the highest levels of energy efficiency and reliability, reducing harmful emissions and saving tremendously in running costs.
"A significant factor in selecting ABB as the supplier for this project was the compatibility between the ABB-supplied variable speed drives (VSD) and the ABB, Nijhuis supplied motors. This compatibility aligned closely with one of the key overall project objectives of sustainability.
“The high efficiency pump-motor-VSD set allowed the Alliance to minimise lifecycle costs. ABB's ability to guarantee an equipment efficiency rating of more than 96 percent played a major role in this decision as it directly translates into affordable potable water,” said Tallaesen, the Project Manager for the pump station.
Adrian Heaton, ABB’s NSW regional sales manager for drives and motors explains why evaluating operating costs is critical for water applications: “Electrical power consumption is one of the largest running costs of a desalination plant that uses reverse osmosis technology. Therefore it was important for WDA to ensure that all the necessary factory and efficiency string tests were carried out in conformance with the contract requirements.
“The string testing involved running the pump, motor and variable speed drives with integral transformers in sequence at actual load conditions to prove minimum lifecycle costs. We are pleased to report that the water pump discharge system, which is capable of discharging water at 3183 litres per second, satisfied the test requirements in every respect. String testing was performed at Nijhuis, the pump manufacturer’s plant in Holland,” said Adrian.
According to Adrian the water consortium’s investment in ABB’s technology will have a huge impact on reducing their daily operating costs because water consumption can vary greatly during any given day. Consequently, the flow and pressure of Nijhuis pumps need to be controlled and adjusted either electrically with variable speed drives, or mechanically with fixed-speed solutions such as inlet guide vanes, throttling valves or hydraulic couplings.
By selecting a variable speed drives solution, changing the flow is achieved simply by changing the motor speed. The pumps can then operate at the best efficiency point under all operating conditions.
Since pumps typically run at partial load, huge energy savings are achieved by controlling their speed with variable speed drives.
WDA’s investment in two 1.35 MW, 3.3 kV high-efficiency motors from ABB’s AMA-family of modular induction machines in combination with drives is even more effective. The energy savings quickly add up because the energy used to run a motor over its lifetime costs 100 times more than the motor itself.