Floating solar panels at Warrnambool’s Brierly Basin expected to reduce power costs by almost half

Warrnambool is “leading the nation” after becoming home to one of Australia’s largest floating solar installations.

The 1,260-panel array at Brierly Basin is now producing electricity as it floats on the water storage that feeds the city’s drinking supply.

Experts believe there is plenty of scope for the technology to be utilised in other industries.

How does it work? The panels generate more than 600,000 kilowatt hours of renewable electricity each year, using “bi-facial” technology, capturing sunlight from above and reflecting light off the water surface. 

Slashing costs: The system is expected to reduce electricity costs linked to pumping water from Brierly Basin to the Warrnambool Water Treatment Plant by around 40 percent annually.

• Wannon Water managing director Steven Waterhouse said the project would help cut costs and emissions while maintaining reliable services. 

• “Projects like this help us use energy more efficiently and keep costs down,” he said in a statement.

• The floating array will also reduce greenhouse gas emissions by more than 600 tonnes each year - the equivalent of taking 130 cars off the road - and supports Wannon Water’s target of reaching net zero emissions by 2030.

The background: Water from Brierly Basin is treated and supplied to more than 19,000 customers across Warrnambool, Koroit and Allansford. 

Work smarter: Nigel Morris is the Chief Strategy Officer for independent energy industry body Smart Energy Council. He told the Brolga floating arrays can generate more power than conventional solar setups.

• “Standard solar panels lose efficiency when they overheat, but the natural cooling effect of water keeps these systems 5°C to 10°C cooler than terrestrial farms,” he said.

• Morris explained this cooling effect, combined with the panels harvesting light reflecting off the water, “boosts energy yields by 15 to 25 percent”.

No small feat: The ability to draw more energy is particularly useful for water utilities, which Morris described as “energy-intensive”.

• “Pumping and treating water requires immense power. With state mandates driving water corporations toward net-zero, floating solar is a natural choice,” he explained.

• “It delivers high-yield renewable energy precisely where the load is needed most, insulating utilities from volatile grid prices.”

The new solar installation’s floating design was chosen because surrounding land could not accommodate a ground-mounted system of the required size - the benefit of the panels shading the water and reducing evaporation from the basin was an added benefit.

Where to next? Morris said the floating solar technology could offer a wide range of uses in other applications, pointing to agriculture as the “next frontier”.

• “Evaporative loss from irrigation storage in NSW and Queensland alone drains 1,320 gigalitres of water annually; saving just 10 percent of that through solar shading represents a $41 million economic boon for crops,” he said.

• While there is no overall data for evaporative loss in Victoria, Agriculture Victoria estimates the average number per dam per year can range from 1200mm to 2000mm. 

• Morris also pointed to heavy industries and mining to install floating solar on industrial ponds to offset diesel emissions.