Research from DTU shows that biochemical products, such as lactic acid, are often not as sustainable as we might think
Today several companies work on producing sustainable industrial chemicals from biomass, such as corn or macroalgae, as alternative to oil as a fossil resource. Chemicals are the fundament of all our products, including plastics, cosmetics, food packaging and biofuels. According to new research results from DTU, using biomass rather than oil for producing chemicals does not automatically make them more sustainable. The results have just been published in Nature Sustainability.
“When we hear that biochemicals are more sustainable than oil-based chemicals, this is usually based on looking at the CO2 footprint only, where the biochemicals generally have the lowest impact. However, if we take a more holistic approach and quantify the wider range of environmental impacts from producing chemicals, we will realize that biochemicals are not necessarily more sustainable”, says Peter Fantke from Quantitative Sustainability Assessment, DTU Management, who coordinated this study.
The study shows how life cycle assessment can guide companies towards more sustainable production methods by identifying problematic environmental “hotspots” in the production of important biochemicals that have been produced from different biomasses with bacterial fermentation.
“There is no doubt that biochemicals are a crucial element for building a more sustainable society. However, there are still challenges in figuring out where the production process needs additional innovation and resources to ensure that biochemicals also become sustainable. Life cycle assessment helps us identify these focus points” – Peter Fantke.
Researcher at the Novo Nordisk Foundation Center for Biosustainability (DTU Biosustain), Ólafur Ögmundarson, who has collaborated on this study with DTU Management, agrees: “The fact that something is ‘bio’ does not always mean that it is better. It depends primarily on modes of production conditions and energy usage at various life cycle stages. Therefore, in general, we need to think and assess the whole life cycle of the product to identify their impacts.”
To apply this life cycle perspective is a core competence in the Quantitative Sustainability Assessment group at the DTU Management department. Researchers and companies are assisted in identifying so-called “hotspots” that are in need of special attention. These “hotspots” are also the areas that researchers and companies should invest their developmental funding in, when trying to make their products more sustainable in an efficient way.
If you measure it, you can fix it
As an example, DTU researchers have analysed different lactic acid production systems in a full life cycle assessment. Lactic acid is used for producing bio-degradable plastics using microbial fermentation of different biomasses. The fermentation process is energy intensive, and for growing the fermentation feedstock, for example corn biomass, agricultural land is needed, where also pesticides and fertilizers are used.
The researchers have, among other things, investigated whether it is possible to make this biochemical product more sustainable by using macroalgae biomass instead. Macroalgae grow fast, do not take up any land, nor do they need use of pesticides or fertilizer. However, given that the algae both need transportation from the ocean to the bio refinery factory, and need to be dried before transportation, it turned out that it was not a better alternative for corn biomass with the current drying technologies in place.
“This type of life cycle assessment should be conducted for all important biochemical products from biofuels to bioplastics to ensure that companies invest their money in the right development from the beginning, and to ensure that we end up with sustainable products in terms of all relevant environmental impacts. Otherwise, we will risk ending up with new products that, worst case scenario, pollute more than the present ones”, says Peter Fantke.
Fact box: Life Cycle Assessment
Life cycle assessment is an ISO standardised method for assessing the environmental impacts from products. It can tell where a company needs to focus improvement efforts to make their product more sustainable. Life cycle assessments record all environmental impacts that come from the raw material sourcing, manufacturer, maintenance, and lastly the disposal or recycling of the product. It is a holistic approach where all parts of the product’s life are analysed as a whole and all relevant environmental impacts are assessed.
DTU is a world leader in this field, and has been researching this specific subject since the early 1990’s, where a major project was launched with companies such as Grundfos, Bang & Olufsen, Danfoss, Gram and KEW. Professor and leader of DTU Management’s Quantitative Sustainability Assessment group, Michael Hauschild has been engaged in this work since then, and experiences an unprecedented surge in interest in in life cycle assessments with the Sustainable Development Goals.
Fact box: further reading
Ólafur Ögmundarson, Markus J. Herrgard, Jochen Förster, Michael Z. Hauschild and Peter Fantke: Assessing environmental sustainability of biochemicals (2020). Nature Sustainability. Read article here: http://doi.org/10.1038/s41893-019-0442-8
Ólafur Ögmundarson, Sumesh Sukumara, Alexis Laurent and Peter Fantke: Environmental hotspots of lactic acid production systems (2020). GCB Bioenergy. Read article: http://doi.org/10.1111/gcbb.12652