Australia’s first commercial solar thermal heat plant to slash gas use at Mars factory

Australia’s first commercial concentrated solar thermal (CST) heat plant will be built in Victoria at the Mars Petcare facility in Wodonga.

The $39 million project will be backed by more than $17 million in funding from the Australian Renewable Energy Agency (ARENA), the new CST heat plant will have capacity of 18MW and boast up to 10 hours of thermal storage.

The CST project will help to reduce 50 per cent of the Mars Petcare facility’s gas use – equivalent to the average annual gas use of over 2,000 households – and will support around 80 jobs during construction, which is expected to get underway almost immediately.

“Our regions have powered the Australian economy for decades and will continue to do so in a net zero world, with a future made in Australia,” said Chris Bowen, Australia’s federal minister for climate change and energy.  

“This is a great demonstration of the potential for renewable technologies like Concentrated Solar Thermal to drive decarbonisation and create regional Australian jobs.

The project is expected to begin operations in 2026 and will use technology provided by Germany’s Solarlite and Belgium-based Azteq.

In a separate statement, Arena said the parabolic trough technology will harness thermal energy from the sun, discharging heated water/steam mixture to a steam drum, to be directed to a series of steam accumulator tanks.

“These tanks will provide up to 150 MWh steam thermal energy storage system to provide round the clock process heating even when the sun doesn’t shine,” it said.

“The project will use water as the heat transfer fluid, storage medium and energy carrier to avoid the requirement for heat exchangers and thermal oil systems commonly utilised in CSP plants.”

ARENA CEO Darren Miller says industry currently accounts for around 44 per cent of Australia’s total emissions, all renewable energy technology options need to be looked at.

“Concentrated solar power has been used for electricity and heat generation for decades overseas, so it’s great to see the renewed interest in it from Mars Petcare in what could be a growing trend for Australian industry in its journey to net zero,” he said.

The technology will complement the site’s existing electric thermal energy storage technology which allows the site to generate low-cost renewable electricity during off-peak times to produce and store heat for later use.

Unveiled earlier this year, the 1 MW, 5 megawatt-hour “graphite battery” installed in partnership with Graphite Energy inputs energy from PV or grid power, and using resistance heaters, can heat graphite up to around 700 degrees Celsius.

Then this heat can be discharged by running water through pipes and producing superheated steam, or stored as a type of battery for later use. It reduced the company’s gas consumption at the factory by 20%.

Mars Petcare, a division of parent company Mars – maker of brands such as Pedigree and Whiskas, M&M’s and Snickers, and MasterFoods and KanTong – says it is on track to transition its Wodonga facility to 100 per cent energy in two years.

Mars completed the transition to 100 per cent renewable electricity for its six Australian factories and two offices back in early 2021, but says a transition to 100 per cent energy requires a complete switch away from all forms of energy, including not only electricity but fossil heat as well.

Global parent company Mars Incorporated celebrated in July its largest single year reduction in greenhouse gas emissions against its 2015 baseline, reducing emissions by 16 per cent across its full value chain.

This marks an important step on the company’s roadmap to deliver a 50 per cent reduction in emissions for its value chain by the end of 2030 and reach net zero by 2050.