The Stockland Wendouree Shopping Centre in Victoria, Australia is using solar-concentrating thermal technology as the sole source of power for their air-conditioning system. Given that a lot of the power consumed by shopping malls, and other such large commercial structures is down to heating and cooling, this is quite a beneficial and sustainable move, and one that more business owners should consider. After all, there is only so much that individuals can do when it comes to assuring a more sustainable future.
The system used by the mall is a prototype and was developed by the CSIRO. It is also partially funded by the Australian Renewable Energy Agency (ARENA) program, which was established in an effort to increase the supply and competitiveness of renewable energy in the country. The newly developed system is basically a “closed-loop” air-conditioner in the sense that it cools and heats the air inside the building without letting in any outside air. It also features two “desiccant” (drying) wheels that function as dehumidifiers and remove the excess moisture from the air. These wheels operate at different temperatures, with the high-temperature wheel using the harvested solar energy for regeneration, while the low temperature wheel does not require any external heat to operate.
Trough collectors are used to capture solar heat of around 302 to 392° F (150 to 200° C), which is then stored in a 528 gallon (2,000-liter) thermal oil tank. Though a heat cascading design, this heat is then used to heat the air in the center in the winter, and also to power an indirect evaporative cooler to keep the interior cool in the summer. The system is also very compact, and the entire solar air-conditioning unit is about 40 percent smaller than a standard single-stage desiccant system.
CSIRO will spend the next 12 months monitoring and assessing the prototype to see how well it functions in a commercial environment. They are, however, confident that such a system will prove successful in reducing the electric power requirements and costs related to supplying humidity in large commercial spaces. The entire system cost just under 1.3 million USD to create and install.