A novel plan for a 50 megawatt hybrid Concentrated Solar Power project in Mount Isa has got financial backing from Queensland government-owned energy giant Stanwell Energy.
The $600 million project, proposed last year by thermal solar specialist Vast Solar, would mix a unique brand of concentrated thermal solar generation with solar PV, gas peaking and a battery to provide power to Mount Isa and the wider North West Minerals Province, which is cut off from the National Energy Market.
Under the joint development agreement announced today, Stanwell will initially provide $5 million towards a feasibility study, with Vast Solar also providing $5 million. The study will examine logistical details, planning requirements, customer off-take, and financing.
Vast Solar chief executive Craig Wood said the study would be finished by the end of the year, and the project would then be ready to take to shareholders for approval.
All going well, he said construction should begin in the second quarter of 2022. He said the plan was for Stanwell to continue as a partner into the construction phase, though that was yet to be negotiated formally.
“It’s a big deal for Vast Solar to be partnered with the largest generator in Queensland. They have a lot of experience in operating assets commercially in the Mount Isa region. It’s a terrific thing to be allied with them,” he said.A novel plan for a 50 megawatt hybrid solar thermal project in Mount Isa has got financial backing from Queensland government-owned energy giant Stanwell Energy.
The $600 million project, proposed last year by thermal solar specialist Vast Solar, would mix a unique brand of concentrated thermal solar generation with solar PV, gas peaking and a battery to provide power to Mount Isa and the wider North West Minerals Province, which is cut off from the National Energy Market.
Under the joint development agreement announced today, Stanwell will initially provide $5 million towards a feasibility study, with Vast Solar also providing $5 million. The study will examine logistical details, planning requirements, customer off-take, and financing.
Vast Solar chief executive Craig Wood said the study would be finished by the end of the year, and the project would then be ready to take to shareholders for approval.
All going well, he said construction should begin in the second quarter of 2022. He said the plan was for Stanwell to continue as a partner into the construction phase, though that was yet to be negotiated formally.
“It’s a big deal for Vast Solar to be partnered with the largest generator in Queensland. They have a lot of experience in operating assets commercially in the Mount Isa region. It’s a terrific thing to be allied with them,” he said.
Wood says the thermal solar technology his company has designed is unique, combining elements from the two major forms of concentrated solar power (CSP): solar towers, and parabolic troughs.
Both technologies use mirrors to concentrate the sun’s rays and heat up a liquid – either oil or molten sodium – which is then used to heat water, creating steam which powers a turbine. Unlike solar PV, CSP can store energy in the molten salt, and provide power when the sun is not shining.
Vast Solar’s technology differs from the tower method in that instead of using one big tower, it uses lots of small towers (around 30 in this case) which brings it closer in some ways to the parabolic trough process. But unlike parabolic trough technology – which first heats up oil, and then transfers that heat to molten sodium – it directly heats the molten sodium. Wood says this makes it much more efficient and allows the molten sodium to reach a higher temperature, as the oil is limited to 400 degrees, but molten salt can reach 600 degrees.
The problem with this method, though, is the molten sodium has tended to damage equipment because it fluctuates in temperature. But Wood says his company has developed a patented technology that solves this problem through the use of a valve that controls flow.
For Mount Isa, the idea is that solar PV will provide power in the day, solar thermal in the night, and any gaps will be filled by backup from a relatively small battery and a gas peaking plant. He said the result would be an 85 per cent reduction in carbon emissions from Mount Isa’s current power supply, which is 100 per cent gas. He said the system would be 99.5 per cent reliable, meaning the hybrid system could be said to provide “baseload” power.
“The ability to provide 85 per cent deacarbonised baseload reliable energy is something that is going to be extremely attractive to other mining companies who otherwise have to pipe in or truck in fossil fuelm” he said.
