They have recently won the Australian Museum’s Eureka Prizes for their breakthrough with a salt-based material that can store energy. Glaciem Cooling Technologies is working on commercializing the idea, so the system may be available on the market soon.
It works by storing the salt solution within a series of coils. The extra solar energy freezes the phase-change material so that it can keep the refrigerator cold when the sun goes down.
By using salt, the solution freezes below 0°C. The solution can reach -6°C, which means that temperatures inside the fridge can be as low as -3°C, according to the researchers.
The solar refrigerator will run entirely on the solar photovoltaics (PV) when the electricity demand is high. The Australian team, from the University of South Australia, wanted the solution to complement solar technology, not replace it.
The salt-based material has already been used for air conditioners for years, and the researchers believe it still has a future in cooling systems as well as the heating and cooling processes used by both the food and chemical industries.
The team’s innovation really boosted the efficiency as well. “Relative to storing solar PV in a battery, which is then used to run the refrigeration system, the overall efficiency is more than 90 percent,” explains Dr. Martin Belusko, a member of the research team.
Glaciem Cooling Technologies, who were formerly known as Quik-Cool, currently have a pilot plant to manufacture the systems. Targeting customers in the dairy industry, the plant can store the equivalent of 1.1 megawatt-hours.