With the world being ravaged by the deleterious effects of global warming and other harmful human activities and practices, the quest is actively on to find alternative sources of energy that do not damage the planet or slow down human civilization. As various countries worldwide recently announce the phasing out of gasoline-powered vehicles, seek to close down fossil fuel-burning power plants, and enact a host of other energy-saving legislation, a remarkable revolution gathers steam in South Australia.
The South Australian government announced a $550 million energy plan back in March this year and has been resolutely seeking to go green. Barely 30 days after finalizing plans with green energy giant Tesla to build the biggest lithium-ion battery storage plant in the world near Jamestown, the state government is this August back in the news. And for good reasons. According to it, in line with its stated goals, it will in partnership with SolarReserve set up a single-tower solar thermal power plant that will be the biggest on this green earth.
“SolarReserve’s energy storage technology is an excellent fit for the South Australian electricity system,” said SolarReserve’s CEO Kevin Smith. “Aurora will provide much needed capacity and firm energy delivery into the South Australian market to reduce price volatility. SolarReserve looks forward to continuing to work with the South Australian government and stakeholders, including the Port Augusta community where the project is located, to support Federal and State renewable energy targets, stimulate long-term economic development, and create new jobs and businesses.”
Aurora Solar Energy Project
Planned power output for this huge plant is stated to be 150 megawatts resulting in 495 gigawatt hours generated yearly. And for those who don’t know it, though only a relative newcomer to the green energy scene, SolarReserve is now one of the heavy-hitters in renewable energy projects worldwide, and is well-respected. According to them, the power plant will create 650 direct construction jobs, 4,000 direct, indirect and induced jobs, and will have a life span of around 40 years, with no discernible degradation being experienced.
The planned power plant has been given the grandiloquent name of Aurora Solar Energy Project. The design is to be based on the innovative Rice Solar Energy Project in ever sunny California that has been indefinitely shelved, owing to tax-related difficulties. Thus, solar energy will be gathered by thousands of mirrors and then focused by heliostats directly to a receiver on top of a 227 meters high central tower. There, the energy is used to power a turbine to produce electricity and is also stored by a rather exotic molten salt technology in the form of heat.
“The Port Augusta story is a stark example of the transition of the South Australian economy, with the closure of a dirty coal-fired power station, and now the commissioning of this world leading renewable energy project,” said South Australia’s Premier Jay Weatherill.
“The Aurora Solar Energy Project will also create new, advanced employment opportunities in regional South Australia,” said South Australia’s Energy Minister Tom Koutsantonis. “We are using our energy plan to drive investment and jobs in this growing sector.”
Aurora Solar Energy Project Will Be Able to Meet Around 5% of the Energy Needs of South Australia
Storage of up to 1,100 MW or 8 hours of full load is possible. As a result, the plant can ceaselessly output power day and night. But will mostly be used during hours of peak power demand to meet shortfalls. It is currently estimated that the Aurora Solar Energy Project will be able to meet around 5% of the energy needs of South Australia – or to power 90,000 homes with renewable electricity.
While there are a few other big solar thermal power plants worldwide, none currently matches the Aurora Solar Project in power output or scope. Sited in California is the Ivanpah Solar Electric plant. This has three towers that churn out 392 megawatts. And in Chile will soon be built a two-tower solar power plant. This will be constructed by the one and only SolarReserve and is scheduled to output 260 megawatts.
Construction of the Aurora Solar Energy Project is planned to begin in 2018 and will cost $650m. It is planned to start producing power by 2020 and will be located near Port Augusta in Northern Australia.
“The Aurora project brings the most advanced power generation technology to South Australia, supporting its energy security and carbon reduction objectives. It also represents a significant opportunity for South Australian workers and businesses to participate in this exciting project,” said Tom Georgis, SolarReserve’s Senior Vice President of Development for SolarReserve.
How it works
Aurora’s functional principle is based on concentrated solar power (CSP). There are different types of CSPs with individual designs. The essential components in the case of the Aurora Solar Energy Project are more than 10,000 mirrors and one solar power tower. The mirrors are ordered circular around the tower. The aim of this formation is to harvest the sun’s energy of a large area hit by the energetic beams. And that is why so many mirrors are applied – to maximise the solar harvest. The solar beams are reflected to one point, called collector or receiver. It is located on the top of the centrally located solar power tower. The concentration of all by the mirrors caught and reflected solar radiation results in extremely high temperatures and a high energy density at the receiver.
The receiver simultaneously acts as a heat exchanger. A circulating fluid works as a heat carrier and captures the concentrated sunlight energy. It is made of molten salt, consisting of sodium nitrate and potassium nitrate, and heated from 500 to over 1000 degrees Fahrenheit. According to SolarReserve, it allows operating at low temperatures. It can even be used to store the heat energy in a thermal storage tank on the ground between 10 to 16 hours until it is needed to generate electricity with an interposed steam generator and the following turbine plus generator.
As the sun is moving during the day, the mirrors are not fixed. Heliostats are used to realize an ongoing reflection to the concentrating point on the top of the tower. It means that each mirror is movable due to an individual tracking system which rotates depending on the position of the sun and the mirror, hence the partially used designation heliostat power plant.