September 11, 2024
Amrita Vishwa Vidyapeetham has developed a new way to harness solar energy using live macroalgae filaments.The university’s research team has achieved promising results, published in the Journal of Science: Advanced Materials and Devices, pointing to a potential future for algae-based solar technology.
The prototype developed by the scientists demonstrated an open-circuit voltage of 0.35 V and a short-circuit current of 10.19 μA. When exposed to UV light with a wavelength of 365 nm, the device generated a photocurrent of 1.25 mA and a photovoltage of 0.5V, all without any external bias. These encouraging results have inspired the research team to explore scalable solutions for this innovative technology.
“Commercializing algal photovoltaic devices is still an emerging field, but our study represents a critical stepping stone. Our research holds significant promise for power generation, particularly in areas with limited access to conventional solar technology,” said Dr. Sudip Kumar Batabyal, the lead researcher.
The research highlights the potential of these algae-based devices as a supplemental power source, particularly in rural areas where conventional solar technology may be economically unfeasible. The team is now focused on scaling up the technology, aiming to integrate it into the broader energy mix.
The study is noteworthy for its use of macroalgae Pithophora roettleri, a variety not commonly utilized in bio-solar devices. Unlike microalgae, which require complex filtration techniques, Pithophora roettleri is easy to harvest, visible to the naked eye, and produces more biomass per unit area, resulting in higher overall energy yields.
Ms. Anamika Chatterjee, the lead author of the study, explained, “The unique properties of Pithophora roettleri make it an ideal candidate for biophotovoltaic devices. Its low nutrient requirement and high carbon absorption capacity further enhance its suitability for large-scale energy generation. However, scalability is always a challenge in research, but our work shows promising potential for generating bioelectricity from freshwater filamentous macroalgae.”
The device, measuring one square centimeter, features a sandwich structure with ruptured macroalgae positioned between two electrodes—a carbon-coated copper electrode on top and a titanium oxide-coated FTO (fluorine-doped tin oxide) glass slide. Tested under various lighting conditions, the device continued to generate low-power electricity even after six months of non-use, demonstrating its durability and resilience.
The team is currently working on building an upscaled model, with a series connection of 10 devices already enhancing voltage output to 5.53V.
This research could pave the way for algae-based energy solutions, potentially serving low-powered IoT devices and addressing localized energy needs, particularly in coastal and rural areas abundant in algae cultivation opportunities.