Fossil resources remain the dominant driver of global warming, accounting for more than 70% of emissions. As policymakers and industry seek pathways to reduce reliance on fossil carbon, attention is turning toward renewable carbon sources such as biomass, captured CO₂, and recycled materials.
Renewable carbon feedstocks originate from the atmosphere, biosphere, or technosphere. Because these sources circulate carbon that is already part of the above-ground carbon cycle, they avoid introducing additional fossil carbon into the system.
The shift away from fossil carbon is increasingly discussed across the chemicals and materials sectors. Yet for many manufacturers, the transition can appear difficult due to supply chain changes, technical requirements, and the need to verify environmental performance.
Some alternatives are already commercially available. Bio-based chemicals derived from fermentation or other biological processes are being used as substitutes for fossil-based intermediates across sectors including coatings, polymers, and cosmetics.
One example is bio-based propanediol produced by Primient, a major manufacturer of the compound marketed under the trade names Zemea PDO and Susterra PDO. Produced through the fermentation of corn-derived dextrose, the material can replace fossil-based glycols or polyols used in polyurethane, coatings, and personal care applications.
Propanediol is a key building block in the chemical industry. Conventional production routes rely on petrochemical feedstocks such as propylene or ethylene oxide derived from crude oil processing.
To assess the environmental performance of its product, Primient commissioned an attributional life cycle assessment of its bio-based propanediol. The study was conducted by TrueNorth Collective and examined the cradle-to-gate impacts associated with the production process.
The analysis evaluated 22 environmental impact categories using the Environmental Footprint 3.1 methodology developed by the European Commission. Particular attention was placed on the climate change potential of bio-PDO compared with a fossil-based benchmark.
Fossil-derived butanediol was selected as the comparison material. BDO is widely used in the production of polyols and polyesters that form part of polyurethane technologies and related applications.
The assessment combined multiple sources of data. Life cycle inventory modelling was conducted using SimaPro 9.5 software.
Primary data for the production process was provided by Primient Covation’s bio-PDO manufacturing operations. Additional primary data was gathered from corn farmers supplying feedstock for fermentation.
Secondary datasets were also incorporated. These included information on bio-PDO from the ecoinvent 3.9.1 database and GREET 2022, alongside fossil-BDO production data sourced from ecoinvent 3.9.1.
The study found a substantial difference in climate change potential between the two materials. Production of bio-based propanediol was associated with a climate impact of 0.71 kilograms of CO₂ equivalent per kilogram of product.
By comparison, fossil-based butanediol production generated 5.12 kilograms of CO₂ equivalent per kilogram. The difference represents a reduction of 4.41 kilograms of CO₂ equivalent per kilogram of product.
This equates to an estimated 86% reduction in carbon footprint compared with the fossil-based benchmark. The comparison was conducted on an equivalent mass basis using a functional unit of one kilogram of material.
The study also addresses how biogenic carbon is treated in life cycle assessments. The carbon embedded in bio-PDO originates from biomass and is temporarily stored within the product.
At the end of the product’s life cycle, that carbon may be released back into the atmosphere. For this reason, the accounting of biogenic carbon uptake within the LCA does not represent permanent carbon removal.
The study notes that if full life cycle emissions were included, similar end-of-life emissions would also apply to fossil-based materials. The cradle-to-gate comparison therefore focuses on production stage impacts.
The findings from Primient’s analysis have gained wider recognition. The peer-reviewed LCA was selected as a benchmark case study in the report Carbon Footprints of Different Renewable Carbon-based Chemicals and Materials.
The report was prepared by the Renewable Carbon Initiative (RCI), a network of companies, research organisations, and stakeholders advocating for the transition away from fossil carbon. The document compiles peer-reviewed case studies examining the climate performance of renewable carbon materials.
The report is expected to inform policy discussions in Europe. Nova-Institute and the Renewable Carbon Initiative are active participants in consultations with the European Commission and the European Parliament on strategies to shift from fossil carbon to renewable alternatives.
These discussions form part of a broader effort to align industrial production with climate targets. The European Union continues to examine policy frameworks that encourage bio-based materials, recycling systems, and carbon capture technologies.
For companies that currently rely on fossil-based chemicals such as propylene glycol, the availability of bio-derived alternatives provides one potential route to reduce emissions in supply chains. Life cycle assessments are increasingly used by manufacturers and regulators to evaluate these transitions.
As industries seek pathways to decarbonise materials and chemical production, renewable carbon sources are expected to play a growing role. Case studies such as the Primient bio-PDO analysis offer data that can help inform decisions by companies, investors, and policymakers considering alternatives to fossil-derived feedstocks.
