Making sensors more sustainable with a greener power source

Sensors are integral to modern life, but rely on power from batteries that generate toxic waste when discarded. Now, a NSW Smart Sensing Network Grand Challenge Fund project has been launched to eliminate the reliance of sensors on disposable batteries by testing the fast production of perovskite photovoltaic (PV) cells, to create a more sustainable sensor power source.

The Revolutionising Indoor Sensor Power: Rapid Microwave Annealing for Ultra-low-cost Perovskite Solar Cells project will be led by Dr Binesh Veettil, a Senior Lecturer in the School of Engineering at Macquarie University.

Veettil said that perovskite cells offer continuous power and are suitable for harvesting indoor light to power low-power sensors. “They are cost-effective when mass manufactured and they are suitable for roll-to-roll manufacturing as they can be screen-printed, slot-die coated or spray-painted. Unfortunately, the lengthy annealing time required is a challenge to be addressed to enable their widespread adoption,” Veettil said.

Annealing is a heat treatment process used to fabricate PV cells. The fabrication of a high-efficiency perovskite cell requires 30 minutes of annealing on a hot plate. Researchers have demonstrated that the same results can be obtained in 30 seconds in a laboratory environment, by using microwave annealing.

“When modified for the roll-to-roll setup of our project industry partner, Halocell Energy Ltd, we aim to increase the speed of the annealing process by 300% while producing the highest-quality semiconductors. This will also help to reduce the energy requirement for annealing by 50%,” Veettil said.

The research findings have the potential to accelerate production and enhance cell quality. The project is a partnership with co-investigator Dr Robert Patterson from the School of Photovoltaic and Renewable Engineering at UNSW and industry partner Halocell Energy Ltd. The project aims to demonstrate the feasibility of this technique in roll-to-roll manufacturing, paving the way for large-scale, eco-friendly indoor sensor deployment.

“This project facilitates an easy solution: indoor-use-optimised PV cells combined with compact supercapacitors for energy storage. This approach not only addresses the pressing issue of toxic waste but also offers a practical benefit to end-users. By providing ‘install-and-forget’ sensors that have no downtime because of battery replacement, we facilitate continuous operation without the environmental burden,” Veettil said.

Image credit: iStock.com/phadventure