The scientific community is increasingly advocating for a transition from the traditional “grey” economy, marked by significant environmental and social drawbacks, towards an economy focused on sustainability and ecological responsibility. This shift highlights the urgent need for innovative technologies that can enhance human well-being while protecting the environment. A crucial element of this transition is the development of cutting-edge, eco-friendly sensing systems and measurement solutions that can be compliant with the “green” approach at every stage of their lifecycle, from raw material selection and production to end-of-life disposal.
In this lecture, I will explore a groundbreaking approach in measurement science that goes beyond consolidated "green" technologies by introducing the "more-than-green" paradigm, through the adoption of nature-based solutions, specifically, living plant-based systems for the development of measurement devices. In fact, unlike traditional silicon-based sensing systems, which contribute to environmental issues through CO₂ emissions during production and pose challenges due to their non-biodegradability and toxicity, the proposed solution is designed to be fully biodegradable and to produce zero CO₂ emissions during manufacturing. This is made possible by eliminating conventional manufacturing and foundry processes. Moreover, the proposed approach not only avoids CO₂ emissions but also actively reduces atmospheric CO₂ through the natural processes of the living organisms, such as photosynthesis, all while functioning as a sensing system.
Entering into more technical detail, I will also present a more integrated vision through a gradual implementation strategy, in which traditional sensing systems are progressively replaced by soil-plant-based solutions. This approach envisions a future where both systems coexist and complement each other, ultimately aiming for a fully "more-than-green" solution. This novel approach emphasizes the development of sensors and components that leverage living plants and their associated metabolic and bacterial processes. In these devices, the metabolic activity of the living organisms is modified in response to specific measurands (such as UVA, visible radiation, magnetic fields, and temperature), resulting in an output voltage that reflects changes in the measured physical quantities. Parameters such as moisture, soil mineralogy, and the presence of other organisms are either controlled or naturally filtered by the selected plant species. Additionally, the structure, shape, and geometry of these plant-based systems are considered functional elements, such as resistors, capacitors, inductors, memory elements, transformers, electrical wires, and filters, for sensor signal conditioning, thereby enabling the realization of a measurement system based on this sustainable technology
In this context, suitable electrically connected plants (such as Dimorphotheca ecklonis, Sansevieria cylindrica, Albuca spiralis, Dionaea muscipula, and soil) will be explored in depth by covering working principles, modeling, equivalent electrical circuits of living systems, simulations, metrological characterization, performance, and experiments that harness the natural sensing capabilities of soil–plant systems to develop generating devices. The obtained characteristics and results demonstrate that these solutions are ideal for a wide range of applications, including environmental monitoring, cultural heritage preservation, security, smart cities, smart homes, domotics and smart agriculture. It is worth emphasizing that case studies and real-world applications will be presented to highlight the technological advancements of these systems, which also feature simplicity, affordability, non-toxicity, battery-free operation, biodegradability, and effective mimetic properties. By seamlessly integrating into their environments and avoiding visual pollution, these measurement solutions represent a significant step toward a more sustainable and ecologically integrated technological landscape. Although a fully industrial level of maturity has yet to be reached, the vision is one of a future driven by “more-than-green” solutions. This lecture aims to share that vision and to present advanced sustainable technologies in measurement systems within a methodologically robust framework