LCA for biobased materials

More and more biobased products are introduced into the market leading to the further development of a biobased economy. They are often considered to be a sustainable alternative to products derived from fossil resources. However, determining the environmental impacts of biobased materials is complicated. Understanding the impact of biobased materials is nuanced, but making a life cycle assessment (LCA) of biobased products helps.

Life Cycle Assessment (LCA) is extremely useful in quantification of environmental impacts of biobased products, and meaningful implementation of low carbon economy and circular economy solutions. The results could be considered to:

• define improvement opportunities for the product manufacturers;
• compare and/or choose between the biobased product and its fossil-based counterpart;
• to decide how using the biobased product would change the environmental performance of the final product its used for;
• make decisions on policies expanding biobased economy.

Due to specific challenges associated with the designing an LCA for biobased materials, the results of an LCA study should be carefully considered. Below, we underpin the main challenges and considerations.

A lot of the emerging biobased materials are in the early stages of development, or just coming to the market. There is limited knowledge on how they would integrate with existing technologies and infrastructures, and without benefitting from the scale effects in the same way as fossil-based materials do. Therefore, LCAs for biobased materials often rely heavily on assumptions and data obtained through modelling rather than collected from real processes. The more assumptions are made and modelling outcomes are used, the less certain the results of the study are in regard to real-life application. Thus, one should be alert when considering the underpinning assumptions and understand what they mean for the study outcomes. Moreover, these assumptions might create a system asymmetry between studies where biobased products are compared with well-established fossil-based alternatives. Thus, if an LCA aims at developing a comparative sustainability claim, it is more akin to comparing an apple with a mystical fruit that has never grown in the garden. Generally possible, but for the claim to hold up to scrutiny, the study should be conservative in its assumptions on how this fruit would grow, what it would need, and if it’s edible at all.

In the modern sustainability landscape, the most attention is given to the challenge of climate change. Therefore, looking at the performance of a product or material, it is tempting to look only at potential impacts associated with climate change, and it will be easy to overlook other impacts. It is true that the use of biobased materials by definition is supposed to reduce the depletion of fossil abiotic resources, however they rely on feedstock that can be very impactful to source in other ways. For example, growing sugarcane for bioplastic production is a big agricultural effort requiring large amounts of land and water. Considering the LCA result, it is useful to look at impacts in all impact categories and to put it in a socio-economic context when used for policy making.

Historically there was a lot of methodological freedom left to the LCA-practitioner on how to account for biogenic carbon (carbon in the shorter natural cycles: taken up from the atmosphere during biomass growth and released back in biomass decay or incineration). However, the methodological freedom created a lot of discrepancies in modelling approaches and categorisation methods used, which can crucially impact the outcomes and the interpretation of the results for biobased products. Look, for example at:

1. How is biogenic carbon accounted for: is it assigned the same impact factors as fossil or not? And consequently: are the results suitable for benchmarking against other studies or for using in combination with other studies?
2. Does the study account for emissions originating in carbon stock changes caused by land use and land use change – for example from growing feedstock? If yes, then how? And what does it mean in the context of the study?
3. How the allocation of the biogenic content (within the final product) is made in production systems where the feedstock is partially biobased and partially fossil-based? Is this allocation accepted by certification framework you look to follow?

To illustrate, we often receive questions regarding the interpretation of the results for use in EPDs and PEF studies. Here, two biogenic carbon allocation approaches are widespread. The mass balance approach says that if 10% of the feedstock for producing 100 products is biogenic, then 10 products are 100% biobased while the other 90 products are 100% fossil-based. In contrast, the mass-based partitioning approach suggests: if 10% of the feedstock is biobased, then each of the 100 products is 10% biobased and 90% fossil-based. Taking into account which approach is used in the study is crucial for driving the conclusions and making decisions for intermediate product use in a final product, and, on a larger scale, for policy making. For instance, both the European Commission recommended Environmental Footprint (EF) method and the construction industry framework EN15804+A2 require to use the mass-based partitioning.

Biobased materials can pose a lot of opportunities, but at the same time they are not an all-encompassing solution, and meticulous studies and careful considerations are crucial for making decisions on using these materials. We should be careful at what moment and in which context technology is suitable for larger-scale implementation. Sometimes, the results might challenge your initial beliefs, but they would offer you the grounds to decide how to move forward.

In Ecomatters, we are familiar with carrying out:

• LCA for biobased products;
• review of LCA studies for biobased products;
• interpretation of LCA results for use in your processes, strategies, and decision-making.

In addition to carrying out LCA for biobased materials, we are also experienced with compliance and legislation for biobased materials. Read more about these services on our Regulation for biobased materials page.

If you are looking for experienced support, we are happy to help you with understanding your position, guiding you through frameworks and reports, advising on the actions and decisions, and carrying out the projects connected with LCA for biobased materials and products.