Aurora solar thermal plant approved in South Australia

GLOBAL solar energy company SolarReserve has announced that it has received developmental approval for its 150 MW Aurora thermal solar plant in South Australia, the largest of its kind in the world.

The Aurora Solar Energy Project will be situated 30 km north of Port Augusta. It will have integrated molten salt energy storage with a capacity of 1,100 MWh. The project is expected to cost around A$650m (US$513m) and will employ around 650 people during construction and 50 permanent staff. SolarReserve says that 4,000 direct and indirect jobs will be created in total by the plant across South Australia.

The Aurora plant will generate around 500 GW/y of energy, around 5% of South Australia’s energy needs, or the equivalent of 90,000 homes, and displace 200,000 t/y of CO₂ emissions. SolarReserve’s technology is already in operation at a 110 MW plant in Nevada, US. At the Aurora plant, more than 12,000 individually controlled dual axis tracking heliostats, with a mirrored area of 1.2m m², will concentrate the sun’s energy on a central receiving tower. Cold molten salt pumped up the tower is heated by the energy to a temperature of 566^oC, and passes back down the tower to a hot salt tank. The hot salt is then used to generate steam, which drives a conventional steam turbine to generate electricity. Cold salt at 288^oC flows back into the cold salt tank for recirculation. Steam is also condensed and recirculated.

The salt battery will provide around eight hours of full-load power during the hours of darkness, meaning the power station will be operational at all times in the same way as a conventional power station.

SolarReserve won a contract from the state government to supply the state of South Australia with energy after a tender process which began in September 2016. Port Augusta’s coal-fired power station closed earlier that year. SolarReserve offered the lowest and most competitive price for its energy, beating bids from conventional fossil fuel power stations.

“This important milestone is a significant step in the development of the Aurora solar thermal power station, which will bring SolarReserve’s world-leading clean power generation technology to South Australia,” said SolarReserve CEO Kevin Smith. “The remarkable story of the transition of Port Augusta from coal to renewable energy – which won a competitive tender against fossil fuel – is also a preview of the future of power generation around the world.”

Construction is expected to begin later in the year.