Photovoltaic cells and AI could revolutionise IoT

Photovoltaic cells that use ambient light to power Internet of Things (IoT) devices. This is the innovation from researchers at Newcastle University in the UK that achieves a power conversion efficiency of 38% and open circuit voltage of 1.0 V at 1,000 lux (corresponding to fluorescent lamps). The non-toxic photovoltaic cells are dye sensitized and use a copper electrolyte.

A paper published in the journal Chemical Science claims that the breakthrough has the potential to revolutionise how IoT devices are powered, making them more sustainable and efficient and opening up new opportunities in sectors such as healthcare, manufacturing and smart cities. “By combining innovative photovoltaic cells with smart energy management techniques, we are paving the way for a multitude of new device implementations that will have far-reaching applications across multiple segments,” says Marina Freitag, principal researcher at Newcastle University’s School of Natural and Environmental Sciences.

The energy management technique developed by the scientists employs artificial neural networks with long-term memory to predict changes in environments and adapt the computational load of IoT sensors accordingly. This dynamic system allows the circuit to operate at optimal efficiency, minimizing power losses or outages and also reducing power consumption. It is a demonstration of the synergy between artificial intelligence and ambient light as a power source, resulting in a new generation of IoT devices.

The innovation allows IoT devices to move away from using batteries, which are unfriendly to the environment and sustainability by requiring frequent replacement, and use surrounding ambient light as a power source. “This marks a paradigm shift for IoT projects” highlights the article. By operating autonomously and dispensing with sophisticated maintenance. This new generation of IoT will be able to be deployed in previously unfeasible locations and volumes. The three main deployment scenarios for this new type of IoT devices are factories, office or retail spaces and homes.

According to the researchers, recently, several photovoltaic technologies have shown promise for indoor applications, all achieving photovoltaic efficiency around 30 per cent.

Energy capture on the rise in 2023

According to a study by ABI Research, 2023 will be a prosperous year for startups working with energy capture, a technology that has increasingly gained the attention of those working with IoT projects by enabling low-cost devices with more energy autonomy. These characteristics represent better return on investment, less maintenance headaches and more capacity to meet sustainability requirements.

According to the survey, energy capture startups for IoT solutions have started to proliferate in the last three years. Many are now reaching the stage of commercialising products at scale. In 2022 alone, about US$110 million was invested in startups in this field. By 2023, this number is expected to grow with gradual funding rounds, helping to popularise this technology and, consequently, the concepts of mass IoT and ambient IoT.

IoT Ambient is a term coined by 3GPP that defines IoT networks with much smaller and cheaper devices whose power source is captured from the environment. Its specifications were included in Release 19 of 5G Advanced and future 6G. According to 3GPP members, this will open the door for wireless operators and other companies to provide interoperable services to billions of IoT devices and solutions.

Besides startups, well-established companies are already showcasing products geared towards ambient IoT in real life, This is the case of Wiliot who, during the last MWC Barcelona 2023 event, showed how its Wiliot IoT Platform combines technologies to put ambient IoT into practice and provide visibility into supply chains, distribution and retail operations. Together with ABI Research and Deloitte, Wiliot also gave a presentation entitled “6G IoT Environment: Antidote to crises in supply chains and climate”.

An IoT Ambient use case presented by Wiliot demonstrates how to secure and simplify the fresh food supply chain. With stamp-sized, battery-free IoT Pixels for IoT Ambiente tags from Wiliot affixed to reusable transport items, distributors and retailers can track food along supply chains, querying temperature, humidity and other condition information to maximise quality and minimise waste.

Academia is also continuing to invest in research to develop materials that can convert waste energy into clean energy more effectively. A group of more than 100 scientists at Simon Fraser University in Canada have worked on analysing various types of energy capture techniques, such as those used in the Ambient IoT, to recommend the best strategy in this field.

“Materials used for energy capture are a promising opportunity to generate clean electricity, improving the energy efficiency of our daily lives and supporting efforts to combat climate change. They can convert ambient energy from various sources, including light, heat, radio frequency waves (such as those from Wi-Fi and mobile communication signals) and mechanical vibrations,” explains Vincenzo Pecunia, professor leading the project in a report on the IET website.

The result of this work is a document that outlines future research directions and aims to catalyse efforts across disciplines. According to the researchers, this is the first time that a large and diverse international network has brought together experts to chart a course for the advancement of these technologies. The roadmap was published in the Journal of Physics: Materials.