The Thermal Energy Storage Group at the University of South Australia have developed a low-cost energy solution that utilizes salt to store excess electricity. Though the use of molten salt batteries for large-scale solar thermal farms for energy storage is not new, the team’s use of salt as a phase-change material has been honored with the ANSTO Eureka prize which celebrates Australian science and innovation.
The team used salt as a phase-change material for smaller-scale, rapid-discharge batteries for residential and commercial use. Instead of heating the salt, the system is charged by freezing the saline solution and discharged by melting it. It is also notable that the researchers managed to bring down the costs by 10 times compared compared to normal solutions.
As the university’s mechanical engineer Associate Professor Frank Bruno states, "this salt-based system is not only cheap but relatively compact for the amount of energy it can store, rapid discharge, and also does not eventually go flat." The team also believes that the storage system can aid in resolving mismatch between generation hours and electricity use which in turn allows more solar and wind power to be fed into the national grid.
pv magazine recently published a