Renewables, Solar, Storage

A crystal clear case for solar PV battery storage

A Queensland water treatment plant is the first off-grid commercial application of Tesla’s Powerpack in Australia.


It takes smart forward planning to manage growth. In South-East Queensland, Logan City Council wanted to prepare for expected strong population growth over the next 20 years but faced the problem of building assets larger than are currently needed. For water infrastructure, it meant controlling the quality of stored water so it would be fresh for residents until rising demand brought faster replacement.

A chlorination station at the 20-megalitre reservoir in New Beith sounded like a good solution. The only problem is the nearest electricity supply is 3.9km away and the reservoir is not accessible via a sealed road.

Sounds like perfect conditions for an off-grid system, and that’s what’s happened, with an electro-chlorinator powered by 323 solar panels and a 50kW (95kWh) Tesla Powerpack now ensuring clean drinking water.

“This is the first off-grid commercial application of Tesla’s Powerpack in Australia and I certainly don’t think it will be the last,” says Ashleigh O’Brien, business manager of CSR-owned installer Bradford Solar.

Unlike Tesla’s Powerwall units used in residential systems the Powerpack is scalable storage solution suitable for commercial and industrial applications.

Logan Water worked out it would cost $1.9 million more than the $3 million project cost to rely on a conventional chlorination system using sodium hypochlorite that could only be delivered if the access road was upgraded. The analysis also showed the operating cost of a solar-powered electro-chlorination system was about $50,000 a year lower than a sodium hypochlorite system, with chlorine produced on site using salt and solar power.

The plant doesn’t need to run 24 hours a day but it can, O’Brien says. “When the sun is up we’re getting optimal efficiency out of the [chlorination] unit. When it’s not running [the solar energy] is stored in the battery for potential rainy periods or poor weather so the system can continue to run.”

Storage makes sense

The water quality analysis and chlorine dosing systems operate 24 hours a day and consume about 10% of the total power demand. The two electrolysers, blowers and chiller only operate during daylight hours to take advantage of the solar power produced. The battery system has been sized to allow the plant to run non-stop during periods of fine and overcast weather.

“For many years these types of solutions were not considered economically viable,” says O’Brien. With the price of systems dropping and the cost of electricity rising, businesses and homeowners are weighing their options.

“Logan Water shows how there is a really good solution now available that could potentially help a lot of remote parts of Australia that are very reliant on very expensive diesel generation,” she says. “Now we have a solution that is not only more sustainable but could also be a lot more affordable. Those that are looking at batteries commercially generally have a fairly unique situation such as this.”

Up to 200,000 people will benefit from the solution by the time the region is fully developed and maintenance is expected to be limited to a couple of visits a year. “It’s designed to run completely automatically.” The Tesla incorporates a cloud-based battery management system to balance out demand and supply.

Send this to a friend