WA’s first pumped hydro microgrid gets underway in Walpole

Construction of Western Australia’s first pumped hydro based microgrid is underway in the fringe-of-grid town of Walpole, with a target for completion of the innovative renewable energy system set for the end of 2023.

The project, which was awarded $2 million in state funding from the Labor McGowan government earlier this month, aims to remedy the notoriously unreliable power supply of the town situated at the southern-most tip of WA, at the end of a 125km long feeder line.

Jointly developed by state-owned utility Western Power and Power Research and WA engineering firm Power Research and Development, the 1.5MW facility will use two farm dams to store 30 megawatt-hours of energy, by pumping water uphill from one dam to another when cheap renewable energy is abundant.

Western Power says on the project page that the microgrid will use solar panels and batteries to provide the power for pumping, making the microgrid totally self sufficient.

During periods of high electricity demand, the water will be released downhill through a generator to provide clean power to the town. In the event of a grid outage, the microgrid can work independently, providing power to local residents and businesses.

Western Power says the microgrid will be able to provide enough power to supply Walpole’s roughly 500 customers for up to two days; “much longer than a typical battery solution.”

“It is also sufficiently sized to support future power needs in Walpole, for example, charging EV’s and smoothing the ebbs and flows of local renewables on the network,” the project page says.

All told, the microgrid has been projected to boost the reliability of Walpole’s power supply by up to 80%.

PRD director Colin Stonehouse said this week that while the project would use “new and clever technology,” generating power from two dams had been inspired by the earliest AC hydro power plant, built in 1892, which was still running today.

“When our collaboration first commenced, Western Power was clear this project should be in Walpole. Since then we have had encouragement and support from the state government, Shire and community, all of which has helped tremendously.

“We must be onto something good because the project has drawn on some of the leading suppliers in the world for its equipment and without exception, they have all wanted to be involved and been very generous with their help.”

WA energy minister Bill Johnston said the Walpole pumped-hydro microgrid was part of the McGowan government’s commitment to improving power reliability in the regions, which had mostly focused on solar and battery-based microgrids or back-up systems.

“Power outages in the town can be disruptive and improving reliability is a priority for Western Power,” Johnston said.

“This project, despite being on a smaller scale, will be used as a template for other areas in the state, and possibly nationally and internationally.”