Key Points
- Chlorella vulgaris biomass grown in wastewater (Metabolon, Germany) is blended with wood powder to create compostable floriculture packaging that fertilises soil after use.
- The material leverages nutrient-rich algae (nitrogen, phosphorus, ammonia) and wood’s slow water-release to support plant growth in a cradle-to-cradle loop.
- Main hurdles were recipe optimisation for mechanical performance and a persistent algae odour; strength was solved with materials engineers, and the natural scent was retained.
- An iterative, material-driven process (casting, drying, laser-cutting) surfaced drying and mould contamination as scale constraints to manage.
- Outlook: microalgae’s versatility and DIY/open-source methods point to broader biomaterial adoption, with partnerships and user testing key to commercialisation.
Full interview with Laura Bordini
What initially sparked your interest in the field of biomaterials and microalgae?
I have been passionate about design since I was little, I started studying it at the age of fourteen, so my academic path has always been quite linear. I graduated with a bachelor's degree in Artistic Planning for the Enterprise in 2020.
At the end of this journey and with all that was going on around me I started to doubt my role as a designer. I have always conceived design as the possibility to improve people's lives and at the time with all the issues that were emerging due to the pandemic, I didn't feel I was fulfilling that purpose.
From that point on, I became interested in sustainable design and the search for more responsible materials. It was then during my Master's in Eco-social design that I started to experiment concretely with what are known as growing materials (mycelium, algae, bacteria). I was fascinated by this world and the possibility of creating products from readily available raw materials that were extremely quick to reproduce and could be replicated anywhere.
Another aspect that really struck me was the concept of democratisation of design. The possibility of creating materials from scratch through DIY (do-it-yourself) practices meant that anyone could create and contribute to the discovery of new solutions, greatly accelerating the material design landscape.
Another aspect that I consider fundamental in this practice is the possibility of working and experimenting with one's own hands. In fact, it is well known how much manual work creates an added value on a psychological level, creating something with our hands inevitably brings us more satisfaction and makes us indirectly happier with what we are doing, and for me this is a fundamental aspect in the working environment.
What are some of the unique properties of microalgae that make them suitable as biomaterials in your opinion?
Algae or microalgae are extremely versatile organisms. Each of them has particular characteristics and applications that vary from species to species. Specifically, I can tell you about my experience with the microalgae Chlorella vulgaris, which I have been working with for an extended period. Chlorella is the most widely used micro-algae in food supplementation in the world after Spirulina.
Apart from this application, however, it can also be used as animal feed,purifying agent for water and air, biogas production, as well as natural dye or ceramic glaze, in textiles, in agriculture and many other sectors.
Specifically, my research focused on the use of the biomass of Chlorella grown in the domestic wastewater of a disposal centre in Germany (Metabolon, Lindlar). This particular situation meant that the microalgae in question contained a high concentration of nutrients, such as ammonia, nitrogen, and phosphorous, to name the most important, which, it was decided to use for the creation of a biomaterial intended for packaging in the floriculture sector.
After testing multiple recipes and combinations, a material mainly made from microalgae biomass and wood powder was defined. The idea was to create packaging that once used could be employed to boost soil fertility, thus creating a productive circularity, where the waste generated by one process becomes an integral part of another, feeding it.
Throughout your biomaterial research journey, what are some of the major challenges and opportunities you have encountered?
The biggest difficulties in the realisation of biomaterials, in my view, are finding the perfect combination and ratio of ingredients in order to obtain a competitive material that can act as a surrogate material to replace other more “polluting” ones.
Another issue in my specific case was related to the smell, microalgae, in fact, possess a very characteristic scent, which is difficult to cover with other natural flavours and this aspect proved to be a major problem for many interlocutors.
As far as the first aspect is concerned, I was able to overcome it thanks to the support of some materials engineers who helped me to create a recipe that reflected the characteristics I wanted to give the material.
As for the smell, several tests were carried out by mixing lemon, orange or mandarin juice, but in no case was it able to cover it. After several trials, it was decided to leave the material unaltered as it was more reflective of its origin, and just as many people were positive about the smell emitted.
What are the environmental benefits or positive impacts that your microalgae-based materials offer compared to conventional materials?
Microalgae have been widely used in agriculture for centuries now, mainly in two stages: to prevent roots from freezing during periods of frost and during blossoming time to stimulate bud growth. After assimilating this knowledge, it was then decided to create a material that could contribute to plant growth, while also exploiting all the nutrients that this specific microalgae had collected during its life cycle.
The combination of microalgae biomass together with wood powder contributes to the creation of a more stable and durable material that can degrade over a longer time. At the same time as the release of nutrients from the microalgae, it also solves the problem of water distribution, as wood is an excellent material for the gradual release of liquids, thus also solving this problem.
Similar practices are already used in agriculture through so-called topsoil, but no one before (to my knowledge) had combined these two ingredients together, resulting in a material of this type. This biomaterial is therefore an excellent alternative to the practices currently in use, contributing to the growth of new plants through a biomaterial derived from our own household waste.
Could you describe the iterative steps or collaborative approaches you employ to ideate, prototype, and refine your packaging creations?
The entire research was based on a trial-and-error approach; it took months to define two ideal recipes that would satisfy the research purpose. Parallel to this, research methods were carried out on potential partners and users to understand their perceptions.
The main method used was the 'material driven design method', which in short would be based on material analysis for a responsible and conscious design of a final product. To do this, sensory evaluation tests were carried out to make the user think about the material's characteristics and possible future applications.
To return to the design of the material, matrices were initially created that resembled a business card on which certain project information was imprinted. These matrices also served as standard shapes to evaluate the reactions of the various recipes. Subsequently, the creation of three-dimensional containers into which the material could be poured was tested, but this option was soon discarded due to problems with drying.
After defining the two final recipes, I began to reproduce them on a larger scale, casting them into wider containers from which a larger surface area could be obtained. This phase brought back some problems related to drying and the easier contamination of the material by mould but meant that more sophisticated packaging could be produced. At the end of the drying process, the material was extracted from the various containers and laser-cut to achieve the desired fit and pattern.
How do the aesthetic qualities or functional properties of microalgae-based materials contribute to the success of the design?
The main design application I submitted my biomaterial to is related to packaging. This solution seemed to me to be an ideal alternative to communicate the purpose and circularity of the project even to non-experts. Packaging is an element that, whether you like it or not, everyone is in contact with daily, so this type of application has a wider impact than other products.
Moreover, the sphere of action is extremely consistent with a cradle-to-cradle process in which the microalgae considered as waste act as a promoter of new life in another process. On an aesthetic level, in addition, the microalgae and wood powder combined make the material solid, pleasant to the touch and with a texture that suggests the raw material and refers to the organic nature of the material with its green-brown tones.
What do you envision for the future of biomaterials and microalgae in terms of research, development, and commercialisation?
Many projects have been realised based on algae or microalgae. In fact, they were widely used in earlier times by various designers who realised their potential and applications. In my experience, the project I realised at the moment has no similar competitors.
Nevertheless, given the development that the world of 'growing materials' is having, supported by DIY practice, I am strongly convinced that this is the future of material design. The perspectives are extremely promising, we are living in a period in which the benefits of self-design and self-production are increasingly pursued, first and foremost to overcome environmental problems, but also economic and social ones. I am convinced that accessibility and the open-source world are the future of collaboration and growth for more resilient and responsible societies.
