In a significant technological achievement, scientists at the CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST) have established a new efficiency record of 35.6% in indoor light harvesting using dye-sensitised solar cells (DSCs). This breakthrough not only offers a sustainable alternative to single-use primary batteries but also has the potential to mitigate environmental pollution. The details of this technological milestone have been published in the Journal of Materials Chemistry A by the Royal Society of Chemistry. C Anandharamakrishnan, Director of CSIR-NIIST, emphasised that integrating DSCs into Internet of Things (IoT) systems can provide a sustainable solution by enabling self-powered devices to operate for extended periods without requiring battery replacements. This innovation is expected to reduce environmental pollution associated with the disposal of billions of used batteries annually, making it a significant advancement for consumer electronics and portable devices. The achievement signifies a noteworthy progress in indoor photovoltaic technology, with DSCs emerging as the leading indoor light-harvesting technology. Their semi-transparent nature, combined with various colours and designs, opens up new possibilities for innovative applications, including integration into glass facades, greenhouses, and architectural installations within indoor spaces. Led by Dr Suraj Soman, a scientist at the Centre for Sustainable Energy Technologies (C-SET) at CSIR-NIIST, the team employed a novel dual-species copper electrolyte approach in their research. DSCs, developed in the 1990s by Michael Gratzel at EPFL, Switzerland, emulate photosynthesis in plants and are known for their eco-friendly and cost-effective nature, making them the preferred choice among indoor photovoltaic technologies. The recent advancement involves careful modification of the copper metal centre?s coordination environment, addressing recombination issues, and enhancing performance, especially in indoor conditions. The CSIR-NIIST team successfully demonstrated the technology by creating a self-powered temperature sensor that operated independently under indoor illumination, eliminating the need for batteries. Dr Narayanan Unni, Head of the Centre for Sustainable Energy Technologies at NIIST, highlighted that powering electronic devices and realising self-powered IoTs through indoor light harvesting would contribute to a greener and more sustainable future by reducing the usage of disposable primary batteries. CSIR-NIIST is actively working on translating this technology into practical applications, developing innovative self-powered prototypes and products, and exploring new applications to significantly reduce dependence on primary batteries. This effort aligns with the goal of reducing the carbon footprint and addressing climate change, as mentioned by Anandharamakrishnan.