VTT Unveils Biodegradable Solar Cell Module for Sustainable Agriculture Innovation

In a groundbreaking development for sustainable farming, VTT Technical Research Centre of Finland has created a lightweight and degradable solar cell module that can be directly attached to plant leaves or stems. This innovation aims to address the increasing digitalization in agriculture, where the reliance on electronics for measurements creates challenges related to power supply and electronic waste.

The solar cell module is about the size of a credit card—flexible and extremely thin. One of its most remarkable features is that it decomposes post growing season, alongside the rechargeable power supply it supports. Maria Smolander, Research Team Leader at VTT, emphasizes the importance of biodegradability in agricultural settings. If the solar cell remains in the field, there’s minimal environmental risk, as it won’t leach harmful substances into the soil and contribute to the microplastics crisis.

Currently, sensor usage in agriculture is relatively low, but this new biodegradable solution could change that. Smolander notes, “this makes it possible to implement sensors more effectively in agricultural applications.”

A Multi-Institutional Collaboration

The solar cell development is part of a three-year international research initiative focused on producing degradable cultivation sensors. In addition to VTT, several prominent institutions are collaborating, including Tampere University, University of Glasgow, and McGill University. Funded by CHIST-ERA and national funding bodies, the project aims to create new environmentally friendly electronics.

Despite agriculture serving as a test platform for this green technology, the broader objective is to explore how to manufacture electronics that are less harmful to the environment, as highlighted by Liisa Hakola, Senior Scientist at VTT.

Tampere University is contributing a battery-like supercapacitor to store energy in conjunction with the solar cell. The project has also developed compostable sensors, designed to relay data wirelessly. Marja Välimäki, Senior Scientist at VTT, explains that the goal is not to generate large amounts of energy but to utilize low-energy sensors to track environmental conditions.

Addressing Environmental Challenges

The biodegradable solar cell introduces new specifications for manufacturing. Traditionally, solar cell materials are designed for durability, but biodegradable options must not decompose prematurely or hasten the breakdown of other components. This poses a challenge as biodegradable materials are often less resilient to environmental stressors like heat and moisture. As Hakola states, “the sensors must be exceptionally light if they are going to be attached to a plant.”

Under varying conditions, the biodegradable solar cells are designed to decompose within weeks or months, with the option of protective mechanisms to regulate their lifespan.

Meeting Regulatory Demands in Agriculture

The farming sector is embracing measurement technologies to enhance agricultural data collection, which assists in improving crop yields, managing plant diseases, and reducing farming-related emissions. Furthermore, regulatory frameworks are demanding more precise measurement data. For example, EU regulations necessitate regular studies of nutrient levels in soil samples. Välimäki highlights that “the new biodegradable solar cell offers a versatile means to harvest energy, enabling real-time data collection and environmental oversight.”

VTT's commitment to developing eco-friendly electronics also aligns with an EU-funded IoT research initiative that merges sensor technology with sustainable solutions in a circular economy.

Overall, VTT's innovative approach may significantly shift agricultural practices towards more sustainable methods, paving the way for a greener future in farming. As environmental awareness continues to rise, integrating biodegradable technologies such as these solar cells could be a crucial step in redefining how we think about agriculture and electronics in harmony with nature.