Hybrid biopharmaceutical manufacturing facilities that combine stainless steel (SSTs) and single-use (SUTs) technologies are the “sweet spot” from an environmental sustainability perspective, according to new research. The research compared the environmental impact—specifically, the carbon footprint— of hybrid facilities with those where SUTs are used, arguing that ongoing efforts to decarbonize energy generation may have shifted the metrics.
And the key findings are that the CO2 footprint of SUTs is significantly higher than previously assumed and that key SST process steps can now have a lower carbon footprint than their single-use counterparts.
Lead author Jan Reiners, rer. nat. , from Roche, tells GEN, “For a long time, SUT was considered more sustainable because it avoids the energy needed to clean and steam-sterilize stainless steel. However, this paradigm has now inverted due to the rapid decarbonization worldwide due to the expansion of renewable energy.
“A single-use run at the 2,000L scale generates up to 6.5 tons of CO2e per batch only in plastic and packaging waste. We didn’t do this assessment for a full stainless-steel system, but the hybrid facility used less than half of plastics,” he adds.
Reiners and colleagues used “market-based emissions accounting” data for the analysis, noting it is becoming common for drug companies to decouple emissions from local energy supplies through tools like power purchase agreements and on-site photovoltaic (PV) installations.
“For instance, our own organization, Roche, has recently achieved its global goal of sourcing 100% sustainable electricity across all worldwide operations. And we are not alone: AstraZeneca is reducing energy emissions by 98% by 2026 and transitioning to 100% renewable energy for heat and power. Novartis claims to have become carbon neutral for energy in 2025, as do many other companies,” he says.
The researchers also found that some long-standing assumptions about SUT systems— for example, that they have lower HVAC costs—no longer hold.
“In modern biomanufacturing, cleanroom ISO classifications remain identical for both SUT and SST due to functionally closed processing, while the massive logistics and warehousing required to store SUT consumables actually expand physical space requirements,” continues Reiners. “And finally, the mass of fossil-fuel-based plastics was underestimated and its CO2 impact actually increased by ~30% in updated global life cycle databases like Ecoinvent v3.12.”
Hybrid alternatives
Considering the findings, Reiners and co-authors suggest that, to minimize emissions and costs, biopharmaceutical manufacturers need to combine stainless-steel systems with SUTs.
“Although SUT is less sustainable, it has other advantages like faster product changeover, more flexibility, less investment, but higher running costs. A hybrid facility is the ‘sweet spot’ of combining SUT and stainless steel to reduce the CO2 impact,” he maintains. “Depending on the facility layout, various measures can reduce the footprint, but per se it is about retaining stainless steel for simple, high-volume, resource-heavy operations—like buffer and media preparation—while keeping single-use for the complex, flexible core process like bioreactors.
“In our study, comparing a full-SUT facility to a hybrid facility reduced the material-related carbon footprint by 62%, dropping emissions from 6.5 tons of CO2e to just 2.8 tons of CO2e per batch.”
